research on white teeth

Effectiveness of Whitening Strips Use Compared With Supervised Dental Bleaching: A Systematic Review and Meta-analysis

• PMID: 33215202
• DOI: 10.2341/19-160-L

Clinical relevance: Bleaching performed at home while under the supervision of a dentist provides greater color alteration compared with whitening strips when evaluated with a spectrophotometer, although the color alteration was undetectable by unaided human eyes.

Summary: Objective: A systematic review and meta-analysis were performed to answer the following research question: Does the use of whitening strips (WS) lead to an equivalent color change compared with supervised dental bleaching in patients with permanent dentition?Methods: A search was performed on August 10, 2017 (updated on March 22, 2019), in PubMed, the Brazilian Library in Dentistry, Latin American and Caribbean Health Sciences Literature database, Cochrane Library, Scopus, Web of Science, and SIGLE, without restrictions regarding date or language. Abstracts from the International Association for Dental Research, unpublished and ongoing trial registries, dissertations, and theses were also searched. Only randomized clinical trials (parallel or split mouth) in patients with permanent dentition that compared WS with dentist-supervised dental bleaching performed at home (AH) or in office (IO) were included. The risk of bias (RoB) was evaluated using the Cochrane Collaboration tool. A meta-analysis with subgroup analysis (low and high peroxide concentration) was conducted for color change ΔE* (spectrophotometer) and ΔSGU (shade guide units), risk and intensity of tooth sensitivity (TS), gingival irritation (GI), and patient satisfaction using a random effects model. Heterogeneity was assessed with the Cochrane Q test and I2 statistics. GRADE (Grading of Recommendations, Assessment, Development and Evaluation) was used to assess the quality of the evidence.Results: After the removal of duplicates, followed by title and abstract screening, 20 studies remained. Only two studies were considered to have a low RoB; 11 had a high RoB, and seven had an unclear RoB. For WS versus IO, data were not available for the meta-analysis. For WS versus AH bleaching, a significant difference in ΔE* favoring the AH group was observed (standardized mean difference [SMD] = -0.50, 95% confidence interval [CI] -0.79 to 0.21), but the risk (risk ratio = 0.78, 95% CI 0.65 to 0.93) and intensity of TS (SMD = -0.30, 95% CI -0.56 to -0.04) were lower in the WS group. Color change in ΔSGU, risk and intensity of GI, and patient satisfaction were not significantly different between groups (p>0.20). The quality of evidence for ΔE*, risk and intensity of TS, and intensity of GI were graded as moderate.Conclusion: Although the risk and intensity of TS were lower in the WS group, dentist-supervised at-home bleaching led to a better color change when measured with a spectrophotometer, although the color alteration was undetectable by unaided human eyes.

©Operative Dentistry, 2020.

Publication types

• Meta-Analysis
• Systematic Review
• Dentin Sensitivity* / chemically induced
• Hydrogen Peroxide / therapeutic use
• Tooth Bleaching Agents* / therapeutic use
• Tooth Bleaching*
• Tooth Bleaching Agents
• Hydrogen Peroxide

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Tooth whitening: Expert help on getting a brighter smile

by Cara Murez

People want whiter teeth, surveys show, and the American Dental Association (ADA) has some advice on how to accomplish that.

Over time, teeth can become less white due to a number of causes, including food and drink, tobacco use , age, trauma and medications.

According to the American Academy of Cosmetic Dentistry, when people were asked what they most wanted to improve about their smile, the most common response was whiter teeth. Meanwhile, about 90% of patients told the American Association of Orthodontists that they also wanted tooth whitening.

Coffee, tea and red wine can all stain teeth because of intense color pigments called chromogens that attach to the enamel on the tooth's exterior, the ADA said in a news release.

Two chemicals found in tobacco—tar and nicotine—also stain. Tar is naturally dark. Nicotine is colorless, but then turns yellowish when mixed with oxygen.

Below a tooth's hard, white outer shell is dentin, which is softer. The enamel gets thinner with brushing and the dentin can show through as you age. A tooth can also change color because it's been injured and creates a thicker layer of dentin.

Certain antihistamines, antipsychotics and high blood pressure medications can also darken teeth. Children who were exposed to antibiotics like tetracycline and doxycycline in utero or as a baby may have discoloration of their teeth as an adult. Chemotherapy and head and neck radiation can also darken teeth, according to the ADA.

Teeth can be whitened using products that contain hydrogen peroxide or carbamide peroxide. The bleaches break the stains into smaller pieces , which affects how the color looks.

Unfortunately, this doesn't work on all teeth. Yellow teeth may bleach well, but those that are brown or gray may not respond as well or at all. Whitening will not work on caps, veneers, crowns or fillings. It also won't work on injured teeth or those changed by medications, according to the ADA.

For those who seek whiter teeth, your dentist can explain your options.

All toothpastes help remove surface stains. Choose a whitening toothpaste that has earned the ADA Seal of Acceptance for stain removal. These have additional polishing agents. Unlike bleaches, these products do not change tooth color because they only remove surface stains.

In-office bleaching requires only one office visit. The dentist uses a protective gel or rubber shield to protect your gums, then applies bleach to the teeth.

You can also get an at-home, custom-made tray from your dentist and bleach your own teeth. You can then whiten your teeth at a slower pace, but still with the guidance of a dentist. This can take a few days to weeks.

Over-the-counter bleaching products can be purchased online or in retail stores. They may include strips or toothpastes that bleach teeth . These have a lower concentration of bleach than products the dentist uses.

It's possible that tooth whitening will cause sensitivity. The peroxide may irritate your tooth nerves. In most cases, this is temporary, but delay treatment if it happens.

Overuse of whiteners can damage the tooth enamel or gums, the ADA added, so don't overdo it.

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• Published: 17 January 2020

A minimally invasive treatment for white spots on teeth

• Niecoo Tajmehr 1  

BDJ Team volume  7 ,  pages 20–23 ( 2020 ) Cite this article

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By Dr Niecoo Tajmehr

Minimally invasive dentistry and the millennial generation

The practice of minimally invasive dentistry is a relatively recent change in approach for dental professionals, with a significant amount of positive evidence becoming available on the subject, especially in the last ten years. 1 Novel techniques and materials are fast being developed for dentists to keep up with the demands of a patient population who are increasingly concerned about the appearance of their teeth. With a rise in social media many patients wish to not only preserve their dentition but enhance it. As a young dentist, it's not difficult to see that our current population's expectations of dental treatment are vastly different to what our predecessors who graduated 20-30 years ago faced. With this in mind, it is vital that we as dental professionals stay up to date with new dental innovations.

So what is ICON?

The ICON (Infiltration CONcept) was designed as a minimally invasive resin infiltration system for treating incipient caries in patients of all ages. 2 The low viscosity unfilled resin, developed by the company DMG (Germany) camouflages white spots by means of optical manipulation, and no tooth tissue removal is strictly necessary.

The clear resin flows into the demineralised enamel, and has similar optical properties (similar refractive index) to the enamel, therefore reflecting light to match the the tooth's natural shade. 3 , 4 , 5

What is a white spot?

White spot lesions are white opacities seen on teeth after the subsurface layer of enamel on a tooth becomes demineralised, often due to poor oral hygiene and plaque, bacteria and acid accumulation on teeth. The decalcified inner enamel remains trapped underneath remineralised surface enamel. The inner demineralised enamel scatters the light due to its irregular microstructure and the result is an opaque white appearance of the tooth.

White spots can also occur on the teeth due to:

Dental fluorosis (a high fluoride intake as the adult teeth are developing)

Congenital hypomineralisation of teeth, due to infection or trauma as infant

Molar incisor hypomineralisation (lack of enamel development during its maturation stage, which affects the molar and incisor teeth)

Decalcification of enamel due to fixed braces (inadequate oral hygiene around the plaque retentive orthodontic brackets).

Working in a dental hospital, white spot lesions on anterior teeth are a common presentation that I see on the paediatric department. However, patients will usually present to their primary care practitioner first. Patients of any age can attend your surgery wishing to hear the options for treatment of their white spots, and it is important to be able to distinguish the cause of the white spot, in order to provide the best treatment outcome. If uncertain, a referral for specialist opinion is recommended.

Aesthetic treatment of white spots

ICON resin infiltration

Tooth bleaching*

Enamel microabrasion

Direct composite resin bonding/veneers

Indirect composite/porcelain veneers*

In severe cases indirect porcelain crowns may be indicated*.

*These treatments are not suitable for children under age of 18 years of age, due to the developing dentition, and the EU regulations for dental bleaching.

A common misconception by dental professionals and patients is that some white spots may be successfully treated with bleaching alone. However, although the overall colour of the tooth will improve, the white spot will remain unchanged and can sometimes even look worse compared to the whiter natural tooth.

A substantial thickness of composite may be required to fully mask a larger white lesion, which can leave the tooth looking bulky. Furthermore, composite and porcelain veneers may require tooth surface preparation which is irreversibly destructive to the tooth.

How is ICON used?

The resin is applied as part of three-part technique. 2 The use of rubber dam is essential to protect the soft tissues. Pre and post-operative photographs are important as part of your record keeping process.

1. Apply Icon-Etch (HCL gel)

Directly onto white spot for two minutes

Agitate, remove with water, gently air dry

2. Apply Icon-Dry (ethanol)

Directly onto white spot

Air dry after 30 seconds

This can be repeated up to five times, until the patient is happy with the appearance of the tooth

3. Apply Icon-Infiltrant (unfilled resin)

Remove excess material and allow to set for three minutes

Light cure each surface for 40 seconds

Repeat infiltration once more with a new tip, remove excess and allow to set, then light cure

Polish as necessary.

The flow chart in Figure 1 , produced by DMG Dental, outlines the process for ICON.

Flow chart outlining the ICON process, produced by DMG Dental

ICON has shown in cases that aesthetic results can be delivered on white spots in a minimally invasive way. 3 , 4 , 5 , 6 This technique should always be used in conjunction with an intensive prevention plan including oral hygiene and diet advice, fluoride varnish placement and regular dental review. Although long term clinical data on this product are limited in the literature, use of this technique is a step forward in allowing patients of all ages to access aesthetic treatment of their white spots, which can significantly impact on their confidence and wellbeing. See Table 1 .

Dental professionals should continue to strive for clinical excellence and improving patient experiences by means of keeping up to date with current and new research in the dental field.

Case example

Enamel opacities on the upper central incisors of an eight-year-old girl treated with ICON ( Fig. 2 ). The opacities were visibly reduced following treatment ( Fig. 3 ) and continued to be at six-month review visit.

Enamel opacities on the upper central incisors of an eight-year-old girl treated with ICON

Stages of ICON application a) Rubber dam application; b) Icon-Etch application; c) Washing; d) Drying; e) Application of Icon-Dry (ethanol); f) Drying; g) Application of resin infiltration (Icon-Infiltrant); h) Flossing between teeth; i) Light-curing; j) Immediate post-operative appearance

Acknowledgements

With special thanks to Professor Helen Rodd, Professor/Honorary Consultant in Paediatric Dentistry, the University of Sheffield, and Dr Noren Hasmun, who kindly provided permission for use of clinical photos from her PhD research conducted at the University of Sheffield, UK.

Author information

BDS (Manchester), MFDS (Royal College of Physicians and Surgeons of Glasgow). Dental Core Trainee 2 in Paediatric Dentistry at Charles Clifford Dental Hospital, Sheffield, UK

Further information

Would you like to submit an original article to BDJ Team for consideration for publication? Just visit our website and click 'submit', or you can email the editor for more information: Kate Quinlan, [email protected] .

Frencken J E, Peters M C, Manton D J, Leal S C, Gordan V V, Eden E. Minimal intervention dentistry for managing dental caries - a review: report of a FDI task group. Int Dent J 2012; 62: 223-243.

DMG Dental. ICON smooth surface - case reports. 2019. Available at: https://www.dmg-dental.com/fileadmin/user_upload/Germany/products/Icon_vestibular/Casebook_IconVE_07022019_en.pdf (accessed 5 December 2019).

Cazzolla A P, De Franco A R, Lacaita M, Lacarbonara V. Efficacy of 4-year treatment of icon infiltration resin on postorthodontic white spot lesions. BMJ Case Rep 2018; doi: 10.1136/bcr-2018-225639.

Manoharan V, Arun Kumar S, Arumugam S B, Anand V, Krishnamoorthy S, Methippara J J. Is resin infiltration a microinvasive approach to white lesions of calcified tooth structures? A systemic review. Int J Clin Pediatr Dent 2019; 12: 53-58.

Omar S. Using resin infiltration to treat developmental defects of enamel. Three case reports. J Restorative Dent 2013; 1: 31-35.

Shivanna V, Shivakumar B. Novel treatment of white spot lesions: a report of two cases. J Conserv Dent 2011; 14: 423-426.

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Authors and Affiliations

DCT2 in Paediatric Dentistry, The Charles Clifford Dental Hospital, Sheffield, UK

Niecoo Tajmehr

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Tajmehr, N. A minimally invasive treatment for white spots on teeth. BDJ Team 7 , 20–23 (2020). https://doi.org/10.1038/s41407-019-0212-5

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DOI : https://doi.org/10.1038/s41407-019-0212-5

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The 9 Best Teeth Whitening Kits, Tested and Reviewed

Whiten and brighten your smile in as little as three days with these dentist-approved teeth whitening kits.

Verywell Health / Jhett Thompson

At-home whitening products have come a long way, and there are many options to choose from. A teeth whitening kit is an easy, effective, and more affordable way to brighten your smile at home. However, for true whitening success, you need to know what type of kit to use and whether or not whitening products are you. Experts recommend avoiding whitening products altogether if you have gum or mouth disease, untreated tooth decay, or significantly worn enamel.

To help you narrow the list of whitening kits that will meet your needs, we tested the best options on the market and evaluated them for ease of use, comfort, efficacy, and value . An orthodontist from our Medical Expert Board reviewed the contents of this article for medical accuracy regarding dental hygiene and the effectiveness of active whitening ingredients.

• Ingredients to Look for and Avoid in Teeth Whitening Kits

According to Rhonda Kalasho , DDS, CEO of TruGlo Modern Denta, carbamide peroxide and hydrogen peroxide are common whitening ingredients. For carbamide peroxide, look for a concentration of around 35%. If you have sensitive teeth, Nina Izhaky , DDS, dentist at Tribeca Dental Studio, suggests 3 to 10%. For hydrogen peroxide, aim for 10 to 15%. Both whiten while causing less sensitivity and side effects than other ingredients.

Steer clear of PAP (or phthalimido-peroxy-caproic acid) on the ingredient label. The dentists we spoke to said they don't recommend this ingredient for whitening due to reports of lingering sensitivity.

• Types of Whitening Products

According to Dr. Kalasho, every tooth whitening system works differently:

• Trays: Like a sports mouthguard, a tray is filled with whitening gel and placed in your mouth for a specific amount each day before being removed. You usually can’t talk much while it’s in, and you can’t eat or drink.
• Light kits: Kits with an LED or UV activator light also work well, says Dr. Kalasho. With these kits, you’ll typically brush on the whitening gel, then insert a lighted tray into your mouth and sit tight for a short period before turning off the kit and removing the tray.
• Gels: Teeth whitening gels are applied to teeth with a small brush to bleach stains using a peroxide-based ingredient. Gels are often used along with trays, but some can be applied, left on for some time, and then rinsed off.
• Pens: Whitening pens allow for easier and more precise on-the-spot whitening, which Dr. Kalasho says is helpful for minor staining. However, most of the whitening washes away with saliva, so more intense stains probably won’t show ultra-noticeable results.
• Strips: Like trays, whitening strips infused with gel are placed on your teeth and left to work their magic for a while. They don’t always stay in place as well as trays, but you can talk more easily, and they may be more comfortable than a bulky tray.

SmileDirectClub Update

On Friday, December 8, 2023, SmileDirectClub announced it was shutting down all production immediately. Though we've tested and included their products in the past, we have removed all of their products from our recommendations in light of this news. We continuously test products and monitor the news to ensure our readers have the most up-to-date information about top products on the market.

• How We Tested
• We Also Tested

What to Look For in Teeth Lightening Kits

Why trust verywell health, best overall, crest 3d sensitive teeth whitening kit.

• Comfort 5 /5
• Effectiveness 4.5 /5
• Convenience 5 /5

Comfortable to use

Immediately whiter teeth

Safe for sensitive teeth

A little expensive

Why We Recommend It

Whitening strips can be a messy, awkward affair, but the Crest 3D Whitestrips for Sensitive Teeth could not have been easier for us to use. The strips were easy to apply and remove . They were also painless, non-irritating , and didn't cause any sensitivity during or after use. And they worked, too—we could see a noticeable difference when we took the first strip off our teeth and felt confident that the results would keep improving from there (with this particular kit, you're directed to use the strips for 28 days).

In terms of convenience and value, we thought the compact, minimal packaging made the strips easy to store. While these strips are a little pricey when considering the quantity, the convenience of seamlessly integrating them into our daily dental routine makes the price worth it. Plus, we thought it delivered real results—our teeth were noticeably whiter after using all 14 strips.

Keep in Mind

They're pricier than some of our other picks.

Type : Strips | Application Time : 30 minutes, once daily | Active Ingredients : Hydrogen peroxide (percentage not specified) 

Best Strips for Sensitive Teeth

Spotlight oral care teeth whitening strips.

• Effectiveness 4.8 /5
• Convenience 3.9 /5

Snug, comfortable fit

Includes convenient carrying case

Need to be worn for one hour

Combining comfort with a gentle formulation, the Spotlight Oral Care Dental Teeth Whitening Strips are our pick for the best strips for sensitive teeth. In testing, we found these strips fit our teeth nicely. We felt like the product effectively adhered to our teeth's front and back. The adhesion created a "vacuum-sealed" effect that made them comfortable to wear for the full hour you're supposed to keep them in place. More importantly, we didn't feel any discomfort or sensitivity during whitening or after wearing these strips, and they worked quickly , too. Our teeth looked visibly brighter after all 14 included strips had been used. 

Considering how well they work, we found these strips to be a great deal. Plus, Spotlight includes a few freebies—notably, a convenient on-the-go travel pouch and vitamin E oil for soothing gums post-treatment, which were much appreciated.

It takes an hour to use these, so these aren't for you if you need something quick for on the go use.

Type : Strips | Application Time : 60 minutes, once daily | Active Ingredients : 0.01% hydrogen peroxide

iSmile LED Teeth Whitening Kit

• Comfort 4 /5
• Effectiveness 5 /5
• Convenience 4 /5

Professional-level whitening

Less messy application

Slightly uncomfortable on the gums

Many whitening products can leave you with a sloppy mess on your hands (and teeth!), but we found the iSmile Teeth Whitening Kit to be a tidier and more effective alternative to some of the other kits we tested. As we tested, we realized you could apply the gel to the mouthpiece before inserting it, which helps ensure you've got the right amount and that all the whitening solution covers your teeth. 

While the application wasn't as comfortable as other picks, the application time here is only 10 minutes , so we thought this was a totally manageable inconvenience for the amount of time needed to whiten. We were surprised how bright our teeth became in testing this product—we felt the kit more than earns its place on our list and is well worth its cost. We even think it may have been more effective than previous whitening treatments we've done in the past at the dentist's office.

We found the whitening process slightly less comfortable. The solution was pretty tasteless, and our gums experienced some discomfort. Swallowing was also awkward because the solution can produce excess saliva, but you aren’t supposed to swallow it.

Type : Gel | Application Time : 10 minutes, once daily | Active Ingredients : 35% carbamide peroxide

Opalescence Tooth Whitening Prefilled Trays

• Comfort 2 /5

Whitens in a short amount of time

Easy to insert trays

Higher strengths may cause sensitivity

These prefilled trays by Opalescence won't be for everyone (people with sensitive teeth, beware!), but they were definitely the easiest and least messy whitening tray option we tested, which is why they're our best tray pick. Essentially, you position the upper and lower trays on your teeth, bite down for a few seconds, and then remove the colored outer tray, leaving behind a more snug-fitting inner tray containing the whitening gel. This allows you to get a snug and comfortable fit every time.

Initially, we couldn't leave the tray in for the recommended 15 minutes because it was so uncomfortable. But over time, we did get used to it. The best part was that our teeth  whitened . Even though we only left it in for about eight minutes, our teeth went up a full shade. It hurt, but the pain was worth it in our eyes. We also started with the highest concentration possible, which we wouldn't recommend if you have sensitive teeth or have never whitened your teeth before (in that case, you may want to start with the lowest concentration and work your way up from there). 

This option isn’t entirely painless. In testing, we found that the upper tray caused serious gum discomfort (even after brushing our teeth to remove the gel). It was similar to the feeling of applying an acid facial peel or retinoid for the first time—painful but bearable. 

Type : Tray | Application Time : 15-20 minutes, once daily | Active Ingredients : 15% hydrogen peroxide

AuraGlow Teeth Whitening Pen

• Comfort 4.5 /5
• Effectiveness 3 /5
• Value 3.5 /5

Whitening on the go

Small, convenient pen to paint on gel

Doesn’t cause discomfort

No “wow” factor with whitening

The main reason to opt for a whitening pen rather than a more comprehensive kit is convenience, and this AuraGlow pen is nothing if not convenient. While the results are more subtle than some of our other picks, the application process is incredibly easy and painless . It's also great that you can easily whiten minor stains on the go. 

The application process is similar to other gel whiteners in that you paint on the product, but after that, you have to allow it to dry (without rinsing or swallowing, which we found to be tricky!). We observed a slight tingling upon application during testing, but nothing persisted. The big bonus here is the pen's convenience ; we liked that there's nothing overly complicated about the whitening process here and that the pen can go with you literally anywhere. We think it could be worked easily into a nighttime brushing routine since you can't eat or drink for an hour after using it.

The effects are more subtle than other picks. If you want on-the-go, light spot treatments then this is perfect. However, this may not be for you if you need a more dramatic or noticeable change.

Type : Pen | Application Time : 1 minute, 1 to 2 times daily | Active Ingredients : 35% carbamide peroxide

Verywell Health / Abby Mercer

Auraglow Whitening Kit

• Convenience 3 /5

Clearly brightens after a few uses

Comfortable and easy to use

Awkward to use

No battery indicator

We were shocked by the Auraglow Deluxe Teeth Whitening Kit's whitening results. The setup process is easy —charge the LED light, fill the tray with gel, and pop it in your mouth—and the tray itself is soft and flexible . Overall, the whitening results were significant enough to make us recommend this product as a good choice, especially since it didn't cause any pain or discomfort and is priced within the average range for a whitening kit. Given how much we know professional whitening costs and remembering the pain and sensitivity we've had with other whitening products, we think this is worth the price.

This pick isn't the most efficient option on the list. It took 30 minutes to work, making our daily activities trickier. It's also rather large and felt clunky. That being said, the results were impressive, so the inconvenience wasn't in vain.

Type : Light kit | Application Time : 30 minutes, once daily | Active Ingredients : 35% carbamide peroxide   

Best Toothpaste

Opalescence whitening toothpaste with fluoride.

Easy to apply

Integrates into your existing brushing routine

Whitens teeth a few shades

Causes discomfort over time

Results don’t last if you discontinue use

It would be best not to head into a whitening toothpaste expecting the same results as whitening strips or a kit with gels and trays. However, a whitening toothpaste, like this one from Opalescence , can help whiten teeth or help maintain a whiter smile over time. We rated it high for convenience , mostly because it functioned like normal toothpaste. We liked that the application process had no learning curve ; it was easy to work into our daily routine and didn’t cause any initial discomfort.

The bottom line is that this product can work, but only under certain circumstances. We think it’s best used for someone who wants to brighten their teeth for an event and doesn’t mind enduring some temporary abrasiveness or for someone who has pretty white teeth and wants to touch up their shade occasionally. 

We noticed some long-term discomfort over time, though, possibly because it felt pretty abrasive. When we stopped, we immediately noticed yellowing and staining. Consistency will bring substantial results, but the heightened sensitivity of the teeth was discouraging for daily use.

Type : Toothpaste | Application Time : Brush as usual, 1 to 2 times daily | Active Ingredients : 0.25% sodium fluoride, 5% potassium nitrate

Best for Fast Results

Oral essentials oral essentials whitening strips.

You can talk while wearing them

Results in under three days

Only covers the most visible teeth

Can leave a film if you don’t brush after removal

We recommend the Lumineux Teeth Whitening Strips if you want whiter teeth fast. Although they do not contain peroxide (opting for a mix of natural ingredients), we found these strips to be a quick and easy way to whiten our teeth in just a couple of days. Not only were these strips easy to apply , but we liked how they tasted refreshing (not plasticky) and didn’t interfere with our conversations (yep, we could talk with these on!). In testing, we observed a gradual lightening of about two shades in under three days, which means you can use these to get a super-short turnaround on brighter teeth.

You get 21 treatments , which we thought was a great value, considering you’ll see results in just three days. We also appreciated that this is an alternative to more chemical-based kits, which makes it a little friendlier for people with sensitive teeth.

The only downside was that the strips only cover the front six to eight of your teeth, so if you were hoping for sparkling molars, this won’t get you there.

Type : Strips | Application Time : 30 minutes, once daily | Active Ingredients : N/A

How We Tested the Teeth Whitening Kits

We tested 21 teeth whitening kits at home. To ensure we got an accurate read on whether the kits had whitening effects, we used a dental color shade chart to find the shade of our teeth before beginning any treatment. We used the products for the first time in our  Verywell Testing Lab  and continued to use them at home according to manufacturer instructions. We assessed them according to the following criteria:

• Ease of use: We assessed how easy it was to understand the directions, set up and apply the product or treatment. We also noted whether the whitening process was messy or clean.
• Comfort: Throughout the testing, we considered whether to apply the product and go about our day as usual. We monitored any changes in sensitivity and discontinued if we noticed irritation.
• Efficacy: We tracked how long it took to see progress and noted when we saw any visible difference in our teeth's shade. Finally, we returned to the Lab and matched our teeth again with the dental color shade chart, recording our results.
• Value: We compared our results and overall performance to the price point to assess whether the value is worth the kit's financial cost.

Teeth Whitening Kits We Also Tested

• GLO Brilliant® White Smile At Home Teeth Whitening Device: In testing, our teeth were much brighter after using this kit, but the 24 minutes we had to spend walking around with an awkward device in our mouth made this a fairly inconvenient option, especially compared to less bulky competitor trays.
• Crest 3D White Whitestrips: These strips were affordable and convenient, but they made our teeth more sensitive, so we had to discontinue testing early.
• SNOW Wireless Teeth Whitening Kit with LED Light: This kit was easy to apply and whitened our teeth well in testing (even when we skipped days due to the battery dying), but it lacks some practicality: Charging it is a pain, as is the fact that there’s no way to know if the battery  needs  charging, and it doesn’t hold a charge for very long.
• Crest Whitening Emulsions Leave-on Teeth Whitening Gel Kit: This was easy to apply with a pleasant, mild taste, but in testing, we saw zero whitening effects—even with the maximum amount of allowed applications per day.
• Colgate Optic White Pro Series Teeth Whitening Pen and LED Tray: If you’re short on time, this kit only requires 10 minutes per day, but it’s not the most comfortable after application (and it’s more expensive than similar kits). 
• Length of application: Generally, Dr. Izhaky says strips are safe to use twice a day for up to two weeks for a maximum of 30 minutes at a time. She adds that gels can be used for one to two hours daily for two weeks, depending on the ingredient percentage. Pens deposit much less product onto your teeth so that they can be used more frequently. However, you should still aim for one to two applications daily (and limit use to one or two weeks at a time or as needed). Trays are commonly recommended for up to 30 minutes, and light kits are usually left in place for shorter periods of time, often less than 10 minutes. The duration for both varies but is usually no more than two or three weeks in total.

Our Experts

When compiling our list, we consulted three dental professionals to learn exactly how teeth whiteners work and get their advice on using them. These experts included:

• Rhonda Kalasho, DDS, CEO of TruGlo Modern Denta
• Nina Izhaky, DDS, dentist at Tribeca Dental Studio
• Kendra Zappia , DDS, dentist and member of the New York State Dental Association

Frequently Asked Questions

Teeth whitening products use common ingredients to minimize the appearance of stains and discoloration on teeth. They do this by bleaching, lightening the appearance of stains, and breaking down and removing them. Typically, in-office whitening procedures are more effective than at-home ones because dentists can use stronger, more concentrated ingredients to whiten (but they’re also usually more expensive). However, the newer wave of at-home whitening products can provide high-quality results.

Yes, it is safe if you use a reputable product, according to Kendra Zappia, DDS, a dentist and New York State Dental Association member. But you should check with your dentist to ensure it's safe for you. Dr. Zappia says that dentists like herself want to ensure patients' mouths and teeth are healthy enough to handle the process, or they can cause more harm than good. Whitening also only works on natural teeth, so  dental work like crowns, bridges, and implants  may also diminish the impact of treatments. Additionally, people who are pregnant should avoid whitening.

Dr. Zappia says some people's effects last three to four months, while others can last up to a year or longer. Drinks like coffee, tea, wine, and soda can stain teeth, shortening the staining's duration.

Dr. Zappia says that bleach in whitening products opens the pores in your teeth to break down the stains. Thus, for safety and efficacy, she recommends brushing and flossing before clearing away any plaque that may interfere with the process and waiting about half an hour so your teeth's pores close back up.

Foods that don't discolor teeth are safe to eat after whitening sessions. Dr. Zappia says cheese, vegetables, pasta, yogurt, and fruits (excluding berries) are good examples of non-staining, post-whitening treats.

Sarah Bradley has been writing health content since 2017: everything from product roundups and illness FAQs to nutrition explainers and the dish on diet trends. She knows how important it is to receive trustworthy and expert-approved advice about over-the-counter products that help you manage everyday conditions.

Loren Brutsch , the editor of this article, has personally tested products on this list and has experienced sensitive teeth from whitening products in the past. She knows how uncomfortable teeth sensitivity from whitening products can be, so she only recommends products she knows are either gentle enough for sensitive teeth or whiten teeth so well that they're worth the discomfort (with a warning from our team, of course).

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How to Naturally Whiten Your Teeth In 3 Minutes at Home (Research Based)

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Even professional whitening performed by a dentist can lead to painful sensitivity, and the methods used are not natural in the slightest. However, don’t give up hope: if you want a brighter, whiter grin, there is a once-a-week method that can have you flashing your pearliest whites—the natural way and you only need a few ingredients such as baking soda and a 3% hydrogen peroxide.

How to Naturally Whiten Teeth Fast At Home in 3 – 5 Minutes

You can naturally and cheaply whiten your teeth at home using just two simple, all-natural ingredients and a toothbrush. You can brush your way to a whiter smile in just a few minutes’ time, once per week. Here’s what you’ll need to whiten your teeth quickly:

1 tablespoon of baking soda (bicarbonate of soda)

A study from 2008 checked the effect of a toothpaste containing baking soda on removing tooth stain and teeth whitening. One group used baking soda and peroxide toothpaste and brushed twice daily with their toothpaste for six week.

The study found a significant improvement in teeth shade score and tooth stain reductions of this group in comparison to the other group that used silica based toothpaste.

A review of 5 clinical studies revealed that baking soda is an effective natural ingredient for removing plaque from teeth . The plaque removal effectiveness of baking soda was significantly greater than the non-baking soda products.

According to another study , baking soda has antibacterial and antimicrobial properties that can help reduce infections.

Since baking soda is alkaline, it neutralizes the acids in the mouth, thus reducing the risk of tooth decay and gum disease . You can also use baking soda as a general kitchen medicine .

You may have heard the claim that baking soda is abrasive. However, compared to commercial toothpastes, baking soda is much less abrasive, and therefore healthier for your teeth.

A small amount of 3% hydrogen peroxide food grade

Hydrogen peroxide (H2O2) comes in a variety of grades designed to address its different uses for disinfection and sterilization. 3% hydrogen peroxide food grade can help to whiten your teeth if used carefully. That means you should avoid higher concentration and not use it too often. Higher concentrations can damage tooth enamel.

A study from 2006 examined the effect of 10, 20 and 30% hydrogen peroxide solutions on human enamel for different periods of time. The research found that higher concentrations of hydrogen peroxide solutions and longer period of time caused more damage to teeth.

The researchers recommended to perform tooth whitening using low concentration of hydrogen peroxide, and shorten treatment time to reduce the possibility of teeth damage but reach the required change in color.

Another study from 2004 checked various concentrations of hydrogen peroxide gel (5, 10, 15 or 25%) on tooth whitening. It found that a person would need 12 applications of the 5% gel to achieve teeth whitening in comparison to one application for the 35% gel.

This means that to prevent damage to your teeth, you will need to use more low-concentration treatments for shorter time in order to achieve your desired teeth whiteness.

You can find other uses for hydrogen peroxide in my article “ Food Grade Hydrogen Peroxide: Ingenious Uses and Benefits “.

A clean, new toothbrush

That’s it! Here is how to put nature’s smile brightener to work for you:

Teeth Whitening at Home – The Method

• Place a tablespoon of baking soda into a small bowl and add a small amount of 3% hydrogen peroxide food grade.
• Mix until you get a paste of a thick consistency.
• Put the paste onto the toothbrush and brush all of your teeth thoroughly, just as you would with regular toothpaste.
• Leave the paste on your teeth for 3 to 5 minutes. Make sure to not swallow any hydrogen peroxide.
• Rinse your mouth out well with plenty of water, and you’re done! That’s all there is to it.

Whitening Teeth with Baking Soda & Hydrogen Peroxide – Things to Consider

– This natural whitening method should be performed no more than once per week in order to get a bright smile without harming the protective enamel covering the teeth.

– It is recommended that you use a fresh, clean toothbrush your first time trying the method and dedicating that toothbrush specifically to being used for whitening—in other words, don’t use your daily-use toothbrush for your whitening treatment.

– According to the National Capital Poison Center , swallowing small amounts of household (3%) hydrogen peroxide is not poisonous to humans. It can cause some irritation and cause a lot of foam in the mouth. If your child swallows some hydrogen peroxide, usually giving a small drink of water or milk is enough to remove the irritation. However, ingesting concentrated hydrogen peroxide (more than 10%) can result in severe injuries like ulcers, internal burning, vomiting, or intense abdominal pain.

– This treatment is not recommended for people who wear dental braces, as it would cause uneven whitening that would be noticeable once the braces were removed.

– After just one month of use (only four treatments) you should begin to see results in the form of a whiter, brighter smile!

Can You Use Baking Soda with Lemon Juice to Whiten Your Teeth?

Some people use lemon juice along with baking soda as a natural toothpaste to whiten teeth. They usually mix 1 tablespoon of baking soda and add the juice of half a lemon to clean their teeth. But you need to be aware that lemon is a naturally acidic fruit.

Some studies have suggested that a mixture of salt and lemon juice has mildly abrasive properties. The cleansing action of sodium and citric acid can help to whiten teeth over time. ( 6 )

A study published in 2015 found that the acidic nature of lemon juice has the potential to weaken tooth enamel. However, the study also noted that apple juice and orange juice can also affect the integrity of tooth enamel. It is also important to note that the research involved soaking a tooth in an undiluted lemon juice for 7 days.

So, when used infrequently , adding lemon juice to baking soda to help whiten your teeth may not have any negative result on your oral health.

More Tips on How to Keep Your Teeth Healthy & White

• There are 13 other natural methods to whiten your teeth .
• Try to avoid these 12 foods and drinks that can cause yellow teeth .
• Learn how to use eggshells to heal cavities .
• You should also consider using this oil as a toothpaste .

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Trump says migrants are fueling violent crime. Here is what the research shows

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WHAT IS TRUMP SAYING ABOUT IMMIGRANTS AND CRIME?

How has biden responded, do immigrants commit more crime than the native born.

• The report, which used data from the Texas Department of Public Safety between 2012-2018, found a lower felony arrest rate for immigrants in the U.S. illegally compared to legal immigrants and native-born U.S. citizens and no evidence of increasing criminality among immigrants.
• Light published a study New Tab , opens new tab in 2017 that found illegal immigration does not increase violent crime. The study used data from all 50 U.S. states and Washington, D.C., from 1990-2014. A separate study found New Tab , opens new tab no link between increased illegal immigration and drunk-driving deaths.
• The libertarian think tank has published multiple New Tab , opens new tab reports New Tab , opens new tab that show immigrants in the country commit crimes at lower rates than the native-born. In a recent USA Today op-ed New Tab , opens new tab , Nowrasteh previewed new research that found immigrants in the U.S. illegally in Texas were about 26% less likely to be convicted of homicide than native-born Americans from 2013-2022.

DO ANY STUDIES FIND IMMIGRANTS MORE LIKELY TO COMMIT CRIMES?

Is it possible that trends have shifted recently.

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Reporting by Ted Hesson in Washington and Mica Rosenberg in New York; Editing by Mary Milliken and Aurora Ellis

Our Standards: The Thomson Reuters Trust Principles. New Tab , opens new tab

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Ted Hesson is an immigration reporter for Reuters, based in Washington, D.C. His work focuses on the policy and politics of immigration, asylum and border security. Prior to joining Reuters in 2019, Ted worked for the news outlet POLITICO, where he also covered immigration. His articles have appeared in POLITICO Magazine, The Atlantic and VICE News, among other publications. Ted holds a master's degree from the Columbia University Graduate School of Journalism and bachelor's degree from Boston College.

Mica Rosenberg leads the immigration team at Reuters, reporting her own projects while helping edit and coordinate cross-border coverage. An investigation she published with colleagues into child labor in the United States – exposing migrant children manufacturing car parts and working in chicken processing in Alabama – was a finalist for the Pulitzer Prize and won a George Polk award among other honors. She was a foreign correspondent reporting from nearly a dozen countries across Latin America and also covered legal affairs and white-collar crime in New York. She completed a Knight Bagehot Fellowship in business journalism and earned a master’s from Columbia’s School of International and Public Affairs. She is originally from New Mexico and is based in Brooklyn.

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8. the changing demographic composition of voters and party coalitions.

Mirroring changes in the U.S. population overall, registered voters have become more educated, more racially and ethnically diverse, older, and more religiously diverse over the past three decades.

Many of these changes have altered the makeup of both parties, but several have had a more pronounced impact on the Democratic Party than the Republican Party.

Race and ethnicity

As the United States has become more racially and ethnically diverse, so too has the electorate.

Today, 67% of registered voters are White, 13% are Hispanic, 11% are Black and 4% are Asian. In 1996, when President Bill Clinton was running for reelection, 85% of voters were White, 4% were Hispanic, 9% were Black and about 1% were Asian.

Both parties are more racially and ethnically diverse than three decades ago, but not to the same degree. There has been more change in the composition of the Democratic coalition than the Republican coalition.

• White voters make up 79% of Republicans and Republican leaners. In 1996, they constituted 93% of the party’s voters. Hispanic voters have tripled from 3% to 9% of the GOP over this period. Black and Asian voters are each currently 3% of the party.
• Within the Democratic coalition, the share who are non-Hispanic White has fallen 21 percentage points since 1996 (from 77% to 56%). The share who are Hispanic has about tripled, from 5% then to 16% today. Asian voters have increased from less than 1% of Democrats’ coalition to 6% over the same period. The share of Black voters within the Democratic coalition has remained fairly stable, and they currently make up 18% of Democratic and Democratic-leaning voters.

Age and the U.S. electorate

The electorate has grown older in recent decades. Currently, about six-in-ten voters are ages 50 and older (29% are 50 to 64 and 29% are 65 and older). By comparison, 41% of voters were 50 and older in 1996.

Reflecting this broader change, both parties’ voters are significantly older now than they were 20 years ago. But today Republican and Republican-leaning voters tend to be older than voters in the Democratic coalition. (In 1996, there was very little difference between the age profiles of the two parties.)

• About two-thirds of voters who align with the Republican Party are 50 and older (32% are 50 to 64 and 33% are 65-plus), compared with slightly more than half of those who associate with the Democratic Party (27% each for ages 50 to 64 and those 65 and older). The share of voters under 30 is twice as large among Democrats (16%) than Republicans (8%). A similar share in each party falls between the ages of 30 and 49 (27% among the Republican Party and 31% among the Democratic Party).

The share of voters with a bachelor’s degree or more has increased significantly among registered voters since 1996, from about a quarter (24%) to four-in-ten today.

Voters with a high school degree or less education have declined roughly in parallel, so that now about three-in-ten have a high school degree or less (28%), compared with nearly half (47%) in 1996. The share of voters with some college experience but no bachelor’s degree has remained relatively stable across this period (32% today, 29% in 1996).

• Among voters who associate with the Democratic Party , the share of voters with a college degree or more has approximately doubled since 1996, from 22% to 45% now. The share of Democratic voters who have no college experience has fallen by about half (from 51% to 25%).
• The Republican coalition has also become more educated, but much more modestly. Today, the GOP’s supporters are divided about equally between those who never went to college (31%), those who attended college but didn’t receive a bachelor’s degree (34%) and those who have a bachelor’s degree or more (35%).

Education by race and ethnicity

The dual trends of increasing education levels and increasing racial and ethnic diversity over the last three decades have resulted in dramatic changes to the electoral landscape.

White voters without a bachelor’s degree remain the largest single group of voters across education levels, race and ethnicity. But where they once represented a clear majority (63%) in 1996, they are now about four-in-ten voters overall (38%).

Overall, about two-in-ten voters are Hispanic (9%), Black (7%) or Asian (2%) and without a bachelor’s degree.

Non-Hispanic White adults with a bachelor’s degree or more represent 28% of voters today, which is up modestly since 1996 (21%). Approximately one-in-ten registered voters are Hispanic (3%), Black (3%) or Asian (3%) and have bachelor’s degrees.

The Republican Party

• White voters without a college degree remain the largest bloc within the Republican coalition, but their share has fallen by 17 percentage points since 1996 (from 68% to 51%).
• 28% of those who associate with the GOP are White voters with a bachelor’s degree, roughly on par with the 25% who were White college graduates in 1996.
• 7% of Republican and Republican-leaning voters are Hispanic without a degree, up from 2% in 1996. Another 3% are Hispanic with a degree (1% in 1996).

The Democratic Party

The Democratic Party does not have a single dominant bloc of voters across education levels, race and ethnicity.

• Three-in-ten voters in the Democratic coalition are White with a bachelor’s degree, up from 18% in 1996.
• About a quarter are White voters without a degree (26%). In 1996, this group made up a majority (59%) of Democratic and Democratic-leaning voters.
• Black voters who do not have a bachelor’s degree make up 13% of the Democratic coalition today, nearly identical to the 14% in 1996, while 5% of Democratic voters are Black college graduates (3% in 1996)
• Hispanic voters without a college degree constitute 11% of Democratically aligned voters today (up from 4% in 1996), while Hispanic voters with a degree are 4% of the coalition (1% in 1996).
• 4% of voters who affiliate with or lean to the Democrats are Asian voters with a bachelor’s degree, and 2% are Asian voters without a degree (in 1996, Asian voters overall made up no more than 1% of all Democratic voters).

Religious affiliation

Americans have become less Christian and less religious in recent decades, and the electorate reflects those changes. Two-thirds of voters identify with a Christian denomination, while about a quarter say they are religiously unaffiliated (26%). Fifteen years ago, about eight-in-ten voters were Christians (79%) and 15% were unaffiliated. (We used different questions about religious affiliation prior to 2008, so comparable data only goes back 15 years.)

These broader trends of declining shares of Christians and increasing shares of religious “nones” have impacted the demographic composition of the two parties’ coalitions in diverging ways.

• The Republican coalition remains overwhelmingly Christian. About eight-in-ten Republican and Republican-leaning voters (81%) identify with a Christian religious denomination, which is down modestly from 2008 when 86% identified as Christian.

Among GOP voters, the shares who identify as White evangelical Protestants (30% now, 33% in 2008) and White Catholics (18% now and in 2008) are little changed over the past 15 years. White nonevangelical Protestants have declined as a share of Republican and Republican-leaning voters from 22% to 15% over the same period, while religious “nones” have grown from 9% to 15% of GOP voters.

• About half of voters in the Democratic coalition are Christian (54%), while 38% are religiously unaffiliated and 8% are of non-Christian faiths. As recently as 2008, Christians made up 74% of Democratically oriented registered voters. Over this time period, the share of religiously unaffiliated voters in the coalition has roughly doubled.

Today, White evangelical (5%) and White nonevangelical Protestants (10%) are 15% of the Democratic coalition, down from 28% 15 years ago. The share of Democratically aligned voters who are Black Protestants has changed very little over this period (15% then to 14% now).

Ideological composition of voters

The electorate continues to have more voters who call themselves conservative than call themselves liberal. About a quarter of voters say they are liberal (16%) or very liberal (8%), while 37% say they are conservative (26%) or very conservative (10%).

Almost four-in-ten voters say they are moderate (36%).

These shares are little changed since 2019.

The Republican coalition is overwhelmingly conservative: 49% of Republican-aligned voters say they are conservative and 20% say they are very conservative. About three-in-ten GOP voters say they are moderate (27%), and there are very few liberal identifiers in the party (less than 5%).

The Democratic coalition is more ideologically mixed than the Republican coalition. Among voters who associate with the Democrats, about half say they are very liberal (16%) or liberal (31%), while nearly as many say they are moderate (45%). Around 6% say they are conservative.

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Table of contents, behind biden’s 2020 victory, a voter data resource: detailed demographic tables about verified voters in 2016, 2018, what the 2020 electorate looks like by party, race and ethnicity, age, education and religion, interactive map: the changing racial and ethnic makeup of the u.s. electorate, in changing u.s. electorate, race and education remain stark dividing lines, most popular.

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White Noise Vs. Brown Noise—Which Can Help Me Get Better Rest?

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If you live in an urban landscape, you may be all too familiar with the sound of traffic rushing past, dogs barking or the voices of people gathering right outside your bedroom window. Even if you don’t live in a highly populated area, you can find yourself trying to block out distracting sounds while you sleep—like a partner snoring logs.

Some research points to the benefits of colored noise for sleep quality. But which is better between ... [+] white noise vs. brown noise?

While it may initially seem a bit contradictory, some people use noise to block out other sounds that would otherwise keep them awake. You may have heard of people using a white noise machine to lull themselves to sleep at night, for instance.

But what about other color sounds; what are the differences between white noise vs. brown noise, and how do you test the waters to find the sound waves that are right for you? We break it down and make it all crystal clear for you.

How To Choose A Mattress, No Matter Your Sleep Preferences

The best pillows for sleep apnea: cpap-friendly, accommodating and comfy, white noise vs. brown noise, white noise.

The concept of white noise is similar to white light. Just as white light features all the frequencies of visible light, white noise contains all audible frequencies at equal intensity. “That is sort of where you get its benefits from, because it creates something like a blanket of sound, where lots of other sounds essentially get absorbed into it,” says Dr. Michael Grandner, a licensed clinical psychologist and director of the Sleep and Health Research Program at the University of Arizona.

White noise sounds like the fuzz on a television screen that has lost its signal. It may also resemble the whirl of a fan or air conditioner. “It's more of a staticky sort of sound,” says Grandner.

Brown Noise

Noise can be expressed as colored, such as white noise, brown noise, pink noise and green noise, among others. Think of white noise as pure noise, with other colors emphasizing certain frequencies more than others.

Brown noise contains all audible frequencies , like white noise, but emphasizes more low frequencies. The sound resembles the sound of inside an aircraft or the crash of the ocean. “It's more like the ocean crashing, whereas ocean waves are less of a hiss,” says Grandner. “Brown noise has more of a rumble to it,” he says.

What Is The Best Color Noise For Sleep?

White noise machines deliver a steady stream of sound to blur more disruptive noises for sleep.

While research is somewhat limited, there are some studies to suggest that white noise can promote better sleep. For instance, one study involving a small group of New Yorkers who were experiencing difficulty sleeping due to environmental noise found that using a white noise device in their bedroom led to improved sleep.

Another study examining white noise and its applications in occupational health states, “White noise (50 to 75 dB) has demonstrated positive and improving effects on the sleep and wake cycle of participants in all the studies in which it was used as an intervention.”

One study from 2022 includes a list of apps and devices that use music, color noises and other relaxing sounds to help people sleep, such as the Hatch Restore . It’s a white noise machine that doubles as a sunset alarm and it made our list for the ten best white noise machines .

However, other researchers express that there are limitations on current research findings, noting the data is difficult to interpret . “Some formal trials or in-laboratory experiments have indeed been conducted delivering white, pink, or brown noise; although it is still not clear given the evidence base whether these are helpful, harmful or neither,” the article states.

The existing research on brown noise, also known as red noise, is even more limited than the research on white noise. “Several prominent international media providers are drawn to the use of brown, purple and blue noise as sound for inducing sleep because it is less disturbing than white noise,” the study on external auditory stimulation notes.

“In addition, many sound sources with color noise such as brown, purple, and blue are uploaded to media such as YouTube under the title of Sleep Induction,” it states. “However, scientific evidence is insufficient as there are few related academic reports,” the study further notes.

How Sound Can Promote Better Rest

While environmental noise is believed to interfere with sleep and negatively impact our health, some sounds, such as white noise, seem to improve sleep for some. “The fact that white noise, of any type, kind of creates this blanket of sound that drowns out other noises, I think that's very well accepted,” says Grandner.

For instance, ones study found that participants fell asleep more quickly when sleeping with filtered white noise as compared to normal environmental noise. But what type of colored noise works best may be a matter of individual preference. “There may be some data to support different frequencies, but none of those are strong enough yet to make a real recommendation,” says Grandner.

More Sounds For Better Sleep

While white noise may be the most commonly talked about of all color noises, there are a couple others that may promote better sleep.

Pink noise has a deeper sound and lower sound waves than white noise, giving it a more soothing quality. Because it has a softer sound, some sleep experts find pink noise to be relaxing and useful as a sleep aid. A Northwestern Medicine study also found that pink noise synced to brain waves could deepen sleep and improve memory in older adults.

Green Noise

Some people tout the benefits of green noise, which emphasizes mid-range frequencies for relaxation. While green noise is not as extensively studied as other color noises, its sound closely resembles those found in nature, which is why some believe it may be useful for improving sleep.

Why Trust Forbes Vetted

Forbes Vetted relies on a combination of medical studies, experts in the field and our own independent research to bring you the latest information on sleep-related issues, as well as the best consumer products for improved sleep. Our team includes certified sleep coaches McKenzie Dillon and Lindsay Boyers who are committed to ensuring you get the highest quality sleep possible.

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United   States-Japan Joint Leaders’   Statement

Global Partners for the Future

Over the course of the last three years, the U.S.-Japan Alliance has reached unprecedented heights. We arrived at this historic moment because our nations, individually and together, took courageous steps to strengthen our collective capacity in ways that would have seemed impossible just a few years ago. Today, we, President Joseph R. Biden, Jr. and Prime Minister KISHIDA Fumio, celebrate this new era of U.S.-Japan strategic cooperation during the Prime Minister’s Official Visit and State Dinner in Washington, D.C.—and pledge that the United States and Japan will continue our tireless work, together and with other partners, to realize a free and open Indo-Pacific and world.

In this new era of U.S.-Japan cooperation, we recognize that global events affect the security and stability of the Indo-Pacific, and that developments in our shared region reverberate around the world. We are therefore working together, across all domains and at all levels, to build a global partnership that is fit for purpose to address the complex, interconnected challenges of today and tomorrow for the benefit of our two countries and the world. As our Alliance cooperation reaches new heights, we are expanding our engagement to reflect the global nature of our partnership.

At the core of our cooperation is a shared commitment to work with like-minded partners and multilateral institutions to address common challenges and to ensure a world that is free, open, connected, resilient, and secure. These joint efforts are based on our shared fundamental respect for international law, including the protection and promotion of human rights and dignity, the sovereignty and territorial integrity of all states, and the prohibition on acquisition of territory by force. Our purpose as partners is to uphold and bolster the free and open international order based on the rule of law that has allowed so many nations to develop and prosper, and to ensure our Alliance is equipped to tackle the challenges of the 21 st century.

To advance our global partnership, today we announce several new strategic initiatives to strengthen our defense and security cooperation; reach new frontiers in space; drive technology innovation; bolster economic security; accelerate climate action; partner on global diplomacy and development; and fortify the ties between our peoples. Through our global partnership, we are also synchronizing our strategies, and our two nations have never been more united as we work together to address the most pressing challenges and opportunities of the future.

Strengthening our Defense and Security Cooperation

The core of our global partnership is our bilateral defense and security cooperation under the Treaty of Mutual Cooperation and Security, which is stronger than ever. We affirm that our Alliance remains the cornerstone of peace, security, and prosperity in the Indo-Pacific. President Biden reiterated the unwavering commitment of the United States to the defense of Japan under Article V of the Treaty, using its full range of capabilities, including nuclear capabilities. Prime Minister Kishida reaffirmed Japan’s unwavering commitment to fundamentally reinforce its own defense capabilities and roles, and to enhance its close coordination with the United States under the Treaty.President Biden also reaffirmed that Article V applies to the Senkaku Islands. We reiterated our strong opposition to any attempts by the People’s Republic of China (PRC) to unilaterally change the status quo by force or coercion in the East China Sea, including through actions that seek to undermine Japan’s longstanding and peaceful administration of the Senkaku Islands. We welcome the progress in optimizing Alliance force posture in areas including the Southwestern Islands to strengthen U.S.-Japan deterrence and response capabilities, and we confirm the importance of further advancing this initiative.

The United States welcomes the steps Japan is taking to fundamentally enhance its defense capabilities, including its plans to increase the budget for its defense capabilities and complementary initiatives to two percent of GDP in Japanese Fiscal Year (JFY) 2027 in accordance with Japan’s National Security Strategy, its decision to possess counterstrike capabilities, and its plans to stand up the Japan Self-Defense Forces (JSDF) Joint Operations Command to enhance command and control of the JSDF. Together, these initiatives elevate our defense ties to unprecedented levels and launch a new era of U.S.-Japan security cooperation, strengthening our Alliance and contributing to stability in the Indo-Pacific.

Today, we announce several new strategic initiatives to further advance our Alliance. Recognizing the speed at which regional security challenges evolve and to ensure our bilateral Alliance structures meet these critical changes, we announce our intention to bilaterally upgrade our respective command and control frameworks to enable seamless integration of operations and capabilities and allow for greater interoperability and planning between U.S. and Japanese forces in peacetime and during contingencies. More effective U.S.-Japan Alliance command and control will strengthen deterrence and promote a free and open Indo-Pacific in the face of pressing regional security challenges. We call on our respective defense and foreign ministries to develop this new relationship through the Security Consultative Committee (our security “2+2”). In support of this vision, we also reaffirm our goal to deepen Intelligence, Surveillance, and Reconnaissance cooperation and Alliance information sharing capabilities, including through the Bilateral Information Analysis Cell.

We will also continue to implement efforts to strengthen our Alliance force posture, build high-end base capabilities, and increase preparedness that are necessary to deter and defend against threats. We resolve to deepen bilateral cooperation toward the effective development and employment of Japan’s suite of counterstrike capabilities, including the provision of U.S. materiel and technological support to enhance Japan’s indigenous stand-off programs. The United States expressed its commitment to start the training pipeline and ship modifications for Japan to acquire operational capability of the Tomahawk Land Attack Missile (TLAM) system. We also reaffirmed our pursuit of a Glide Phase Interceptor (GPI) cooperative development program to counter high-end, regional hypersonic threats.

As our countries strengthen our bilateral ties, we will continue to build our relationships with like-minded partners in the region. Today, we announce our vision to cooperate on a networked air defense architecture among the United States, Japan, and Australia to counter growing air and missile threats. Recognizing Japan’s strengths and the close bilateral defense partnerships with the AUKUS countries, AUKUS partners – Australia, the United Kingdom, and the United States – are considering cooperation with Japan on AUKUS Pillar II advanced capability projects. Continuing the momentum from the Camp David Summit, we welcome progress on establishing an annual multidomain exercise between the United States, Japan, and the Republic of Korea (ROK). Recognizing the commitments made in the Atlantic Declaration and the Hiroshima Accord, and as the Indo-Pacific and Euro-Atlantic regions become ever more interlinked, we welcome the announcement of regular U.S.-Japan-UK trilateral exercises, beginning in 2025, as we enhance our shared and enduring security. Building on the announcement at the Australia Official Visit in October to pursue trilateral cooperation with Japan on unmanned aerial systems, we are exploring cooperative opportunities in the rapidly emerging field of collaborative combat aircraft and autonomy.

The United States welcomes Japan’s revision of the Three Principles on the Transfer of Defense Equipment and Technology and its Implementation Guidelines, which bolsters cooperation through joint development and production to enhance our deterrence capabilities in the region. To leverage our respective industrial bases to meet the demand for critical capabilities and maintain readiness over the long term, we will convene a Forum on Defense Industrial Cooperation, Acquisition and Sustainment (DICAS) co-led by the U.S. Department of Defense and Japan’s Ministry of Defense to identify priority areas for partnering U.S. and Japanese industry, including co-development and co-production of missiles and co-sustainment of forward-deployed U.S. Navy ships and U.S. Air Force aircraft, including fourth generation fighters, at Japanese commercial facilities, in coordination with relevant ministries. This forum, in conjunction with our existing Defense Science and Technology Cooperation Group, will better integrate and align our defense industrial policy, acquisition, and science and technology ecosystems. The DICAS will provide updates on progress to the foreign and defense ministers in the security “2+2.” We also commit to establishing a working group to explore opportunities for future fighter pilot training and readiness, including AI and advanced simulators, and co-development and co-production of cutting-edge technologies such as common jet trainers to maintain combat-ready next-generation fighter airpower.

We reaffirm the critical importance of continuing to enhance U.S. extended deterrence, bolstered by Japan’s defense capabilities, and will further strengthen bilateral cooperation. In this regard, we call on our respective foreign and defense ministers to hold in-depth discussions on extended deterrence on the occasion of the next security “2+2” meeting.

We continue to deepen our cooperation on information and cyber security to ensure that our Alliance stays ahead of growing cyber threats and builds resilience in the information and communication technology domain. We also plan on enhancing our cooperation on the protection of critical infrastructure.

Recognizing the importance of rapidly responding to frequent and severe climate change-related and other natural disasters, we plan to explore cooperation on the establishment of a humanitarian assistance and disaster relief hub in Japan.

In order to maintain deterrence and mitigate impact on local communities, we are firmly committed to the steady implementation of the realignment of U.S. forces in Japan in accordance with Okinawa Consolidation Plan, including the construction of the Futenma Replacement Facility at Henoko as the only solution that avoids the continued use of Marine Corps Air Station Futenma.

Reaching New Frontiers in Space

Our global partnership extends to space, where the United States and Japan are leading the way to explore our solar system and return to the Moon. Today, we welcome the signing of a Lunar Surface Exploration Implementing Arrangement, in which Japan plans to provide and sustain operation of a pressurized lunar rover while the United States plans to allocate two astronaut flight opportunities to the lunar surface for Japan on future Artemis missions. The leaders announced a shared goal for a Japanese national to be the first non-American astronaut to land on the Moon on a future Artemis mission, assuming important benchmarks are achieved. The United States and Japan plan to deepen cooperation on astronaut training to facilitate this goal while managing the risks of these challenging and inspiring lunar surface missions. We also announce bilateral collaboration on a Low Earth Orbit detection and tracking constellation for missiles such as hypersonic glide vehicles, including potential collaboration with U.S. industry.

Leading on Innovation , Economic Security, and Climate Action

The United States and Japan aim to maximally align our economic, technology, and related strategies to advance innovation, strengthen our industrial bases, promote resilient and reliable supply chains, and build the strategic emerging industries of the future while pursuing deep emissions reductions this decade. Building on our efforts in the U.S.-Japan Competitiveness and Resilience (CoRe) Partnership, including through the U.S.-Japan Economic Policy Consultative Committee (our economic “2+2”), we intend to sharpen our innovative edge and strengthen our economic security, including by promoting and protecting critical and emerging technologies.

The United States and Japan welcome our robust economic and commercial ties through mutual investment, including Microsoft’s $2.9 billion investment in Japan on AI and cloud infrastructure, workforce training, and a research lab; and Toyota’s recent additional $8 billion battery production investment for a cumulative $13.9 billion investment in North Carolina. Japan is the top foreign investor in the United States with nearly $800 billion in foreign direct investment, and Japanese companies employ nearly 1 million Americans across all 50 states. Similarly, as a top foreign investor in Japan for many years, the United States is supporting Japan’s economic growth, and as two of the world’s largest financial sectors, we commit to strengthening our partnership to bolster cross-border investment and support financial stability. As robust and creative economies, we also plan to accelerate investment in our respective start-up environments to foster innovation through the “Japan Innovation Campus” in Silicon Valley and the “Global Startup Campus” to be established in Tokyo, and in companies that take actions toward sustainable value creation (SX). We welcome our new Japan-U.S. personnel exchange programs on startups and venture capital firms under the Global Innovation through Science and Technology (GIST) initiative.

We are committed to strengthening our shared role as global leaders in the development and protection of next-generation critical and emerging technologies such as AI, quantum technology, semiconductors, and biotechnology through research exchange and private investment and capital finance, including with other like-minded partners. We welcome our collaboration on AI for Science between Riken and Argonne National Laboratory (ANL) founded on the revised project arrangement.

We applaud the establishment of $110 million in new AI research partnerships – between the University of Washington and University of Tsukuba and between Carnegie Mellon University and Keio University – through funding from NVIDIA, Arm, Amazon, Microsoft, and a consortium of Japanese companies. We are committed to further advancing the Hiroshima AI Process and strengthening collaboration between the national AI Safety Institutes.

Building on our long history of semiconductor cooperation, we intend to establish a joint technology agenda for cooperation on issues such as research and development, design, and workforce development. We also welcome the robust cooperation between and with our private sectors, especially in next-generation semiconductors and advanced packaging. We also plan to work together along with like-minded countries to strengthen global semiconductor supply chains, particularly for mature node (“legacy”) semiconductors through information-sharing, coordination of policies, and addressing vulnerabilities stemming from non-market policies and practices. We also celebrate the signing of a Memorandum of Cooperation between Japan’s National Institute of Advanced Industrial Science and Technology (AIST) and the U.S. National Institute of Standards and Technology (NIST) as a first step in bilateral cooperation on quantum computing.

Building on the Indo-Pacific Economic Framework for Prosperity (IPEF) and our respective leadership of the G7 and Asia-Pacific Economic Cooperation (APEC) last year, we continue to advance resilience, sustainability, inclusiveness, economic growth, fairness, and competitiveness for our economies . We applaud the recent entry into force of the IPEF Supply Chain Agreement. We will continue to seek cooperation on critical minerals projects, including those along the Partnership for Global Infrastructure and Investment Lobito Corridor, and through the Minerals Security Partnership (MSP) as well as the Partnership for Resilient and Inclusive Supply-chain Enhancement (RISE). We are cooperating to deter and address economic coercion, through our bilateral cooperation as well as through our work with like-minded partners including the G7 Coordination Platform on Economic Coercion. We are working to uphold a free, fair and rules-based economic order; address non-market policies and practices; build trusted, resilient, and sustainable supply chains; and promote open markets and fair competition under the U.S.-Japan economic “2+2” and the U.S.-Japan Commercial and Industrial Partnership. We will advance our commitment to operationalize data free flow with trust, including with respect to data security. We will also discuss the promotion of resilient and responsible seafood supply chains.

The United States and Japan recognize that the climate crisis is the existential challenge of our time and intend to be leaders in the global response. Towards our shared goal of accelerating the clean energy transition, we are launching a new high-level dialogue on how we implement our respective domestic measures and maximize their synergies and impacts, including the U.S. Inflation Reduction Act and Japan’s Green Transformation (GX) Promotion Strategy aimed at accelerating energy transition progress this decade, promoting complementary and innovative clean energy supply chains and improving industrial competitiveness. Today we announce Japan joins as the first international collaborator of the U.S. Floating Offshore Wind Shot. We intend to work together towards global ambition in line with the Wind Shot, taking into consideration national circumstances, through the Clean Energy and Energy Security Initiative (CEESI) to pursue innovative breakthroughs that drive down technology costs, accelerate decarbonization, and deliver benefits for coastal communities. The United States welcomes Japan’s newly-launched industry platform, the Floating Offshore Wind Technology Research Association (FLOWRA), aiming to reduce costs and achieve mass production of floating offshore wind through collaboration with academia.

We are further leading the way in developing and deploying next generation clean energy technology, including fusion energy development through the announcement of a U.S.-Japan Strategic Partnership to Accelerate Fusion Energy Demonstration and Commercialization.

The United States remains unwavering in its commitment to support the energy security of Japan and other allies, including its ability to predictably supply LNG while accelerating the global transition to zero-emissions energy and working with other fossil energy importers and producers to minimize methane emissions across the fossil energy value chain to the fullest extent practicable.

We intend to advance widespread adoption of innovative new clean energy technologies, and seek to increase the globally available supply of sustainable aviation fuel or feedstock, including those that are ethanol-based, that show promise in reducing emissions.

We are also working to align global health security and innovation, including in such areas as pandemic prevention, preparedness, and response and promoting more resilient, equitable, and sustainable health systems. Today, we announce that the U.S. Food and Drug Administration and the Japan’s Pharmaceuticals and Medical Devices Agency (PMDA) intend to collaborate and exchange information on oncology drug products to help cancer patients receive earlier access to medications and to discuss future drug development and ways to prevent drug shortages. We welcome PMDA’s future representative office in Washington, D.C., to facilitate this cooperation.

Partnering on Global Diplomacy and Development

The challenges we face transcend geography. The United States and Japan are steadfast in our commitment to upholding international law, including the UN Charter, and call for all Member States to uphold the Charter’s purposes and principles, including refraining from the threat or use of force against the territorial integrity or political independence of any State. We remain committed to reforming the UN Security Council (UNSC), including through expansion in permanent and non-permanent categories of its membership. President Biden reiterated support for Japan’s permanent membership on a reformed UNSC.

We reaffirm our commitment made in Hiroshima last year and are determined to further promote our cooperation in the G7 and work together with partners beyond the G7.

We emphasize the importance of all parties promoting open channels of communication and practical measures to reduce the risk of misunderstanding and miscalculation and to prevent conflict in the Indo-Pacific. In particular, we underscore the importance of candid communication with the PRC, including at the leader level, and express the intent to work with the PRC where possible on areas of common interest.

We emphasize the importance of all States being able to exercise rights and freedoms in a manner consistent with international law as reflected in the United Nations Convention on the Law of the Sea (UNCLOS), including freedom of navigation and overflight. We strongly oppose any unilateral attempts to change the status quo by force or coercion, including destabilizing actions in the South China Sea, such as unsafe encounters at sea and in the air as well as the militarization of disputed features and the dangerous use of coast guard vessels and maritime militia. The PRC’s recent dangerous and escalatory behavior supporting its unlawful maritime claims in the South China Sea as well as efforts to disrupt other countries’ offshore resource exploitation are inconsistent with international law as reflected in UNCLOS. We also emphasize that the 2016 South China Sea Arbitral Award is final and legally binding on the parties to that proceeding. We resolve to work with partners, particularly in ASEAN, to support regional maritime security and uphold international law.

We emphasize that our basic positions on Taiwan remain unchanged and reiterate the importance of maintaining peace and stability across the Taiwan Strait as an indispensable element of global security and prosperity. We encourage the peaceful resolution of cross-Strait issues.

We continue working together with partner countries to make concrete progress in strengthening the international financial architecture and fostering investment under the Partnership for Global Infrastructure and Investment. We are committed to delivering better, bigger, more effective multilateral development banks including through our planned contributions that would enable more than $30 billion in new World Bank lending and securing ambitious International Development Association and Asian Development Fund replenishments. We also emphasize the importance of private sector investment in the Indo-Pacific. We welcome the announcement of Google’s $1 billion investment in digital connectivity for North Pacific Connect, which expands the Pacific Connect Initiative, with NEC, to improve digital communications infrastructure between the United States, Japan and Pacific Island Nations. Building on the U.S.-Australia joint funding commitment for subsea cables last October, the United States and Japan plan to collaborate with like-minded partners to build trusted and more resilient networks and intend to contribute funds to provide subsea cables in the Pacific region, including $16 million towards cable systems for the Federated States of Micronesia and Tuvalu.

We reaffirm our steadfast commitment to the Quad and its shared vision of a free and open Indo-Pacific that is stable, prosperous, and inclusive which continues to deliver results for the region. We reiterate the Quad’s unwavering support and respect for regional institutions, including ASEAN, the Pacific Islands Forum (PIF), and the Indian Ocean Rim Association. We also reaffirm our support for ASEAN centrality and unity as well as the ASEAN Outlook on the Indo-Pacific. Southeast Asian countries are critical partners in the Indo-Pacific and the U.S.-Japan-Philippines trilateral aims to enhance trilateral defense and security cooperation while promoting economic security and resilience. Japan and the United States reaffirmed our intention to work to support the region’s priorities as articulated through the 2050 Strategy for the Blue Pacific Continent, including through the PIF as the Pacific’s preeminent institution as well as through the Partners in the Blue Pacific (PBP).

As we pursue our shared vision of a free and open Indo-Pacific, we continue to build strong ties between key, like-minded partners in the region. Building on the historic success of the Camp David Trilateral Summit, the United States, Japan and the Republic of Korea continue to collaborate on promoting regional security, strengthening deterrence, coordinating development and humanitarian assistance, countering North Korea’s illicit cyber activities, and deepening our cooperation including on economic, clean energy, and technological issues. The United States and Japan also remain committed to advancing trilateral cooperation with Australia to ensure a peaceful and stable region.

We reaffirm our commitment to the complete denuclearization of North Korea in accordance with relevant UNSC resolutions. We strongly condemn North Korea’s continued development of its ballistic missile program—including through launches of intercontinental ballistic missiles (ICBM) and space launch vehicles using ballistic missile technologies—which poses a grave threat to peace and security on the Korean Peninsula and beyond. We call on North Korea to respond to continued, genuine offers to return to diplomacy without preconditions. We call on all UN Member States to fully implement all relevant UNSC resolutions, especially in light of Russia’s recent veto. We urge North Korea to cease illicit activities that generate revenue for its unlawful ballistic missile and weapons of mass destruction programs, including malicious cyber activities. President Biden also reaffirms U.S. commitment to the immediate resolution of the abductions issue, and the two sides commit to continuing joint efforts to promote respect for human rights in North Korea.

We continue to stand together in firm opposition to Russia’s brutal war of aggression against Ukraine, its strikes against Ukraine’s infrastructure and the terror of Russian occupation. We are committed to continuing to impose severe sanctions on Russia and provide unwavering support for Ukraine. Together, we reiterate our call on Russia to immediately, completely, and unconditionally withdraw its forces from within the internationally recognized borders of Ukraine. Any threat or use of nuclear weapons in the context of its war of aggression against Ukraine by Russia is unacceptable. We also express serious concerns about growing North Korea-Russia military cooperation, which is supporting Russia’s war of aggression against Ukraine and threatens to undermine peace and stability in Northeast Asia as well as the global non-proliferation regime.

As the linkages between the Euro-Atlantic and the Indo-Pacific regions have become stronger than ever, our two countries look forward to continuing to work together to enhance Japan-North Atlantic Treaty Organization (NATO) and NATO-Indo-Pacific Four partnerships.

We once again unequivocally condemn the terror attacks by Hamas and others on October 7 of last year, and reaffirm Israel’s right to defend itself and its people consistent with international law. At the same time, we express our deep concern over the critical humanitarian situation in the Gaza Strip. We affirm the imperative of securing the release of all hostages held by Hamas, and emphasize that the deal to release hostages would bring an immediate and prolonged ceasefire in Gaza. We affirm the imperative of realizing an immediate and sustained ceasefire in Gaza over a period of at least six weeks as part of a deal that would release hostages held by Hamas and allow for delivery of essential additional humanitarian assistance to Palestinians in need. We underscore the urgent need to significantly increase deliveries of life-saving humanitarian assistance throughout Gaza and the crucial need to prevent regional escalation. We reiterate the importance of complying with international law, including international humanitarian law, as applicable, including with regard to the protection of civilians. We remain committed to an independent Palestinian state with Israel’s security guaranteed as part of a two-state solution that enables both Israelis and Palestinians to live in a just, lasting, and secure peace.

We reaffirm the importance of supporting inclusive growth and sustainable development in Latin America and the Caribbean. We continue to enhance policy coordination in the region, in particular on Haiti and Venezuela. We also recognize that promoting the stability and security for Haiti is one of the most pressing challenges in the Western Hemisphere, and we continue to support Haiti in restoring democratic order.

We also support African aspirations for peace, stability, and prosperity based on the rule of law. We continue to work together to support the democratic process and economic growth through our respective efforts, including our cooperation with African countries, Regional Economic Communities, the African Union, and multilateral organizations.

The United States and Japan are resolved to achieve a world without nuclear weapons through realistic and pragmatic approaches. It is critical that the overall decline in global nuclear arsenals achieved since the end of the Cold War continues and not be reversed, and the PRC’s accelerating build-up of its nuclear arsenal without transparency nor meaningful dialogue poses a concern to global and regional stability. We reaffirm the importance of upholding the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) as the cornerstone of the global nuclear disarmament and non-proliferation regime and for the pursuit of peaceful uses of nuclear energy. In promoting this universal goal of achieving a world without nuclear weapons, Japan’s “Hiroshima Action Plan” and the “G7 Leaders’ Hiroshima Vision on Nuclear Disarmament” are welcome contributions. The two leaders also welcomed the U.S. announcement to join the Japan-led “Fissile Material Cut-off Treaty Friends” initiative. We reaffirm the indispensable role of the peaceful uses of nuclear technology, committing to fostering innovation and supporting the International Atomic Energy Agency’s efforts in upholding the highest standards of safety, security, and safeguards. President Biden commended Japan’s safe, responsible, and science-based discharge of Advanced Liquid Processing System treated water at Tokyo Electric Power Company’s Fukushima Daiichi Nuclear Power Station into the sea. Our two countries plan to launch the Fukushima Daiichi Decommissioning Partnership focusing on research cooperation for fuel debris retrieval.

To effectively address the myriad challenges outlined above, our global partnership is launching a Deputy Secretary of State/Vice Minister for Foreign Affairs-level dialogue involving our respective aid agencies to align our diplomatic and development efforts globally.

Fortifying People-to-People Ties

People-to-people exchanges are the most effective way to develop the future stewards of the U.S.-Japan relationship. In this regard, we recognize the achievements of exchange programs between our two countries, including the Japan Exchange and Teaching (JET) Programme, KAKEHASHI Project, the Japan Foundation’s programs, and the U.S.-Japan Council’s TOMODACHI Initiative, and commit ourselves to providing more opportunities to meet today’s needs, including through enhanced subnational exchanges on critical issues such as climate and energy. We also recognize the important role civil society has played in strengthening the U.S.-Japan relationship over the past 170 years, including the 38 Japan-America Societies across the United States, the Asia Society, and the 29 America-Japan Societies across Japan.

Building on the Memorandum of Cooperation in Education signed between us on the sidelines of the G7 Leaders’ Summit in Hiroshima, today we announce our commitment to increase student mobility through the new $12 million “Mineta Ambassadors Program (MAP)” education exchange endowment administered by the U.S.-Japan Council for U.S. and Japanese high school and university students who will “map” the future of the relationship with support from Apple, the BlackRock Foundation, Toshizo Watanabe Foundation, and other founding donors. In this regard, we also welcome Japan’s new initiative to expand scholarship for Japanese students through the Japan Student Servicers Organization.

We recognize the significant contributions made by the binational Japan-U.S. Educational Commission (Fulbright Japan) over the past 72 years. We welcome recent changes to upgrade the program by reopening scholarships to Science, Technology, Engineering, and Math (STEM) fields for the first time in 50 years, with the first STEM students on track to participate in academic year 2025-26, as well as removing the tuition cap for Japanese Fulbright participants to attract the highest quality students and researchers.

Celebrating the 30th anniversary of the establishment of the Mansfield Fellowship Program, we honor the legacy of Ambassador Mansfield’s contributions through the University of Montana Mansfield Center and Mansfield Foundation. The two leaders also welcome the creation of the Government of Japan endowed Mansfield Professor of Japanese and Indo-Pacific Affairs at the University of Montana.

Upon the 100 th anniversary of the birth of the late Senator Daniel K. Inouye, who made incredible contributions to our bilateral relationship, we praise the efforts of Japanese American leaders to build a bridge between the two countries and to address common community issues, including through support to the U.S.-Japan Council’s newly launched TOMODACHI Kibou for Maui project. We also share the recognition on the importance of exchanges between our legislatures. We acknowledge the importance of language study, particularly in person, to develop long-term ties and announce a new Memorandum of Cooperation to increase opportunities for the number of exchange visitors from Japan to share their specialized knowledge of Japanese language and culture in the United States, as well as welcome efforts to expand the Japanese Language Education Assistant Program (J-LEAP).

The two leaders also affirm that women in leadership remain their focus and reaffirm our pledge to achieving gender equality and the empowerment of women and girls in all their diversity. We welcome close cooperation on Women, Peace, and Security and Women’s Economic Empowerment initiatives and efforts to promote women and girls’ full, equal, and meaningful participation and leadership in public life.

Finally, we emphasize the need to build a diverse pipeline of future U.S.-Japan experts who understand and support the Alliance. Our peoples form the core of our Alliance, and we reaffirm our commitment to forge ever-closer bonds for generations to come.

Through our shared and steadfast commitment, we have taken bold and courageous steps to bring the U.S.-Japan Alliance to unprecedented heights. In so doing, we have equipped our partnership to protect and advance peace, security, prosperity, and the rule of law across the Indo-Pacific and the globe so that everyone benefits. Today, we celebrate the enduring friendship among our peoples—and among ourselves—and pledge to continue our relentless efforts to ensure that our global partnership drives future peace and prosperity for generations to come.

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• v.2018; 2018

Efficacy of Dental Bleaching with Whitening Dentifrices: A Systematic Review

Bruno g. s. casado.

1 School of Dentistry, University of Pernambuco (UPE), Camaragibe, PE, Brazil

Sandra L. D. Moraes

Gleicy f. m. souza, catia m. f. guerra.

2 School of Dentistry, Pernambuco Federal University (UFPE), Recife, PE, Brazil

Juliana R. Souto-Maior

Cleidiel a. a. lemos.

3 School of Dentistry, Dental Materials and Prosthodontics, São Paulo State University (UNESP), São Paulo, Araçatuba, Brazil

Belmiro C. E. Vasconcelos

Eduardo p. pellizzer.

A systematic review was performed to evaluate whether whitening toothpastes promote tooth whitening when compared to the use of conventional (nonbleaching) dentifrices. This review was registered at PROSPERO (CRD42017065132) and is based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Electronic systematic searches of PubMed/MEDLINE, Scopus, and the Cochrane Library were conducted for published articles. Only randomized clinical trials in adults that compared the use of so-called whitening dentifrices to the use of nonwhitening dentifrices were selected. The outcome was tooth color change. Twenty-two articles from 703 data sources met the eligibility criteria. After title and abstract screening, 16 studies remained, after which a further five studies were excluded. In total, nine studies were qualitatively analyzed. Significant differences in tooth color change were found between the groups using whitening dentifrices and those using nonwhitening dentifrices. Within the limitations of this study, the evidence from this systematic review suggests that bleaching dentifrices have potential in tooth whitening. However, although many whitening dentifrices have been introduced into the dental market for bleaching treatments, it is important to analyze tooth surface and color changes when performing home bleaching.

1. Introduction

Tooth discoloration is one of the most commonly reported complaints in patients seeking aesthetic treatment. Variation in tooth color can be influenced by intrinsic and extrinsic factors, ranging from chemical ingestion to consumption of foods that cause staining [ 1 , 2 ].

Currently, there are several products on the market that remove stains and claim to whiten teeth. Options range from simple professional prophylaxis and the application of bleaching gels to vital teeth for home use or supervised in a dental office [ 3 ]. Bleaching gels normally consist of different concentrations of hydrogen peroxide or carbamide peroxide and involve various forms of application. Furthermore, these different applications result in different mechanisms of activation, which provide dental bleaching through oxi-reduction reactions, based on partial oxidation of the active principle, through which the whitening agent alters the structure of pigment molecules, thus promoting tooth whitening [ 4 , 5 ].

Several companies have developed bleaching toothpastes, which are considered an alternative to home and/or dental whitening procedures, and which promise bleaching results within 2 to 4 weeks. These toothpastes thus offer increasingly simpler and less costly bleaching methods for those wishing to have whiter teeth [ 6 , 7 ]. Many of these bleaching toothpastes contain hydrogen peroxide, whereas others contain abrasive components, which promote the removal of extrinsic stains [ 7 , 8 ].

These abrasives may remove blemishes from the coronary surfaces, giving rise to the idea that alterations in tooth coloration have occurred, which is often used as a marketing strategy by companies to show that teeth are healthy. However, little is known about the efficacy of these bleaching dentifrices compared with conventional (nonbleaching) dentifrices and their effects/alterations on stained teeth regardless of etiology [ 7 , 9 , 10 ].

Therefore, the objective of this systematic review was to evaluate whether whitening toothpastes promote tooth whitening when compared to the use of nonbleaching dentifrices. The hypothesis of the study is that bleaching dentifrices do not promote tooth whitening.

2. Materials and Methods

2.1. protocol registration.

The current systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The methods used in this review are registered on PROSPERO (CRD42017065132).

2.2. Research Methods

The selection of articles was performed individually by two authors (Bruno G. S. Casado and Cleidiel A. A. Lemos) using published papers found in the Cochrane Library, PubMed/MEDLINE, and Scopus databases from inception to December 2017. The following terms were used in the search strategy: “tooth bleaching and dentifrice OR dental bleaching and dentifrice OR tooth bleaching and toothpaste OR dental bleaching and toothpaste.”

Two researchers also manually searched for papers published up to December 2017 in specific journals such as Dental Materials and Journal of Dentistry and Operative Dentistry. A third author (Gleicy F. M. Souza) determined divergences in paper selection by the researchers and a consensus was obtained through discussion.

2.3. Eligibility Criteria

The selection criteria included randomized clinical trials (RCTs) and articles published in English. The exclusion criteria included prospective and retrospective studies, crossover studies, in vitro studies, animal studies, mechanical studies, case reports, and literature reviews.

2.4. Search Strategy

Clinical studies were selected from the title and abstract through electronic searches conducted by two independent researchers. In studies where it was not possible to obtain sufficient information, the complete article was downloaded. After reading the title and abstract, the studies that did not meet the inclusion criteria were excluded.

The following specific question was elaborated based on the population, intervention, control, and outcomes criteria: “Do bleaching dentifrices effectively promote tooth whitening?” According to these criteria, the population was composed of patients who used dentifrices, and the intervention was the use of so-called whitening dentifrices compared with the use of nonwhitening dentifrices. The evaluated outcome was the efficacy of bleaching dentifrices on tooth color change.

2.5. Risk of Bias and Evaluation of Study Quality

Two investigators (Bruno G. S. Casado and Cleidiel A. A. Lemos) evaluated the methodological quality of the included studies using bias analyses based on the Cochrane criteria for assessing the risk of bias. This tool assessed the quality and risk of bias of the included studies based on sequence generation, allocation concealment, blinding of participants, personnel or outcome investigator, incomplete outcome data, selective outcome reporting, and other sources of bias and was rated as low/high or unclear risk of bias according to the studies evaluated.

2.6. Data Collection and Analysis

The data collected from the articles were classified as quantitative and qualitative by one researcher (Bruno G. S. Casado) and then verified by another researcher (Gleicy F. M. Souza). All disagreements were resolved by a third researcher (Cleidiel A. A. Lemos) through discussion until a consensus was reached. Quantitative and qualitative data were tabulated to aid the comparison.

2.7. Additional Analysis

An additional analysis was performed using the kappa coefficient, which was calculated to establish the interexaminer agreement in study selection from the three databases. The kappa value was obtained by evaluating the titles and abstracts selected. The Cochrane Library ( K  = 0.94), PubMed/MEDLINE ( K  = 0.71), and Scopus ( K  = 0.92) showed a high level of agreement.

The database search identified a total of 703 articles, 287 of which were from PubMed/MEDLINE, 303 from Scopus, and 113 from the Cochrane Library. After removal of duplicate references and a thorough review of titles and abstracts, 16 studies were read in full. After reading, nine studies were excluded ( Table 1 ). Details regarding the search strategy are presented in the flow diagram ( Figure 1 ).

Flow chart showing the steps in the literature search.

Reasons for exclusion of “9” articles.

In total, seven studies were selected for qualitative analyses and are summarized in Table 2 . All selected studies were RCTs published between 2001 and 2016. A total of 1,399 patients with a mean age of 36.89 years were included in the studies, of which 879 used some type of dentifrice considered to be a bleaching agent by the manufacturer. The groups of patients evaluated varied according to the dentifrice, and the effectiveness of nine products was tested: Arm & Hammer® Advance White® Extreme Whitening Baking Soda and Peroxide Toothpaste ( n =86), Arm & Hammer® Truly Radiant Toothpaste ( n =59), Crest® 3-D white radiant mint toothpaste ( n =56), Crest® Extra whitening ( n =363), Colgate® Simple White® Advanced Whitening Toothpaste Sparkling Mint ( n =21), Colgate® Baking Soda Peroxide ( n =216), Colgate Luminous White® ( n =32), Close-Up White Now® ( n =31), and Oral B 3D white ( n =15).

Summary of characteristics of included studies.

∗ Groups with significant statistical difference. NI, not informed.

The bleaching effectiveness of the studied dentifrices was evaluated. Four studies showed that the products evaluated were effective in bleaching teeth using the VITA color scale (subjective method), and three studies showed that the products were effective in bleaching teeth using spectrophotometry (objective method).

In relation to daily brushing frequency, most studies [ 20 – 24 ] reported that using toothpaste twice a day increased tooth whitening, but two studies indicated that patients who brushed three times a day were more likely to have whiter teeth. In addition, the follow-up period ranged from 5 days to 8 weeks, with the most common period being 4 weeks (six studies). All studies included in this review examined subjects who used conventional toothpaste (not considered to have a bleaching effect by the manufacturers) as the control group.

The relevance of the articles included in this systematic review was considered satisfactory as all studies were RCTs with a low risk of bias ( Figure 2 ). We included Cochrane randomized clinical trial studies to determine the bias scale in each study. All included studies were characterized as double-blind (randomized studies were performed with the patient and the evaluator blinded to the product), which is considered important in understanding responses in experimental clinical research.

Cochrane scale for bias risk.

3.1. Bleaching Effectiveness

In the four studies that evaluated tooth color change using the VITA shade guide, all studies [ 20 , 22 – 24 ] reported that bleaching dentifrices were effective for tooth whitening when compared with regular dentifrices ( p < 0.05). However, Gerlach et al. [ 20 ] found differences between the groups only in the evaluation period following 4 weeks of dentifrice use.

In the studies that used a spectrophotometer to analyze tooth whitening, two studies [ 21 , 25 ] demonstrated that bleaching dentifrices differed in relation to conventional dentifrices. However, Horn et al. [ 25 ] tested three different dentifrices, and found that only the use of Colgate Luminous White® had a tooth-whitening effect after 2 weeks. In agreement, a study by Pintado-Palomino et al. [ 7 ] showed that most bleaching and control dentifrices showed similar clinical performances, without a significant chromatic reduction, during a 4-week follow-up period.

4. Discussion

The results of this systematic review indicate that most of the included studies showed a significant change in dental coloration following the use of commercially available bleaching dentifrice agents when used for a period of between 5 days and 8 weeks.

Although peroxide bleaching materials are well-established for aesthetic tooth whitening, the use of these substances in dentifrices is quite limited [ 25 ]. In addition to causing alterations in products, high concentrations of hydrogen peroxide need to be counterbalanced by the use of soft tissue protective barriers in order to maintain contact with dental surfaces, which is not the case with bleaching toothpastes [ 8 ].

However, Isaacs et al. [ 21 ], Kakar et al. [ 22 ], and Ghassemi et al. [ 23 ] observed that the presence of 1.0% hydrogen peroxide in the chemical formulation of dentifrices caused tooth coloration changes when compared with nonwhitening toothpastes. These findings agreed with those obtained by Sharma et al. [ 17 ] who demonstrated the bleaching potential of these dentifrices and concluded that the presence of hydrogen peroxide was able to significantly interfere with dental chromatic alterations over a brushing period of 2 to 6 weeks. Therefore, it is important to consider the concentration of hydrogen peroxide and its contact time as important contributors to effective tooth whitening [ 19 ].

On the other hand, studies by Gerlach et al. [ 20 ], Horn et al. [ 25 ], and Ghassemi et al. [ 24 ] tested bleaching dentifrices that were free from any type of peroxide and obtained satisfactory results regarding changes in tooth coloration during the use of these toothpastes. These results may have been due to the presence of high performance abrasive agents contained in the bleaching dentifrices such as silica, which was present in almost all products included in this review [ 7 , 21 – 25 ]. These abrasive agents promote the gradual physical removal of extrinsic pigments without effectively whitening teeth. Therefore, these bleaching dentifrices are sometimes considered only as surface spot removers [ 7 , 8 , 25 ].

Interestingly, the studies by Hilgenberg et al. [ 26 ] and Özkan et al. [ 27 ] showed that bleaching dentifrices promoted morphological changes on the surfaces of tooth enamel. Therefore, it is important to consider that brushing with toothpastes containing abrasive substances should be done with caution, as the indiscriminate use of dentifrices with large quantities of these agents can lead to irreversible damage of hard dental tissues and restorative materials; they can also lead to recession of the gingiva, abrasion in the cervical region, and in some cases, dentin hypersensitivity [ 8 , 26 ].

Another limiting factor is that these studies did not use similar evaluation methods, making it difficult to compare the parameters studied in the coloration change analyses in this review. Dozic et al. [ 28 ] proposed that the spectrophotometer was the most reliable instrument on the market for tooth coloration analysis; the accuracy of the results is related to the positioning of the equipment at the same point of the dental surface at all times of analysis [ 14 ].

However, among the studies selected in this review which used spectrophotometry as the evaluation method, only the study by Isaacs et al. [ 21 ] demonstrated a significant color change following use of the bleaching dentifrices. This probably occurred because the products tested by Isaacs et al. [ 21 ] contained hydrogen peroxide associated with a high performance silica. These results are in agreement with those by Sharma et al. [ 17 ], who confirmed that these two substances in a dentifrice were able to remove extrinsic stains, reducing the yellow color pigmentation ( b ∗ parameter) of the teeth, when compared to conventional dentifrices.

The findings of Horn et al. [ 25 ] and Pintado-Palomino et al. [ 7 ], who also used spectrophotometry as a method of evaluation, did not show a significant difference between bleaching and conventional dentifrices, a factor justified by the absence of hydrogen peroxide in the dentifrices tested. Although in the study by Horn et al. [ 25 ], a statistical difference was shown in one of the test groups (Colgate Luminous White dentifrice) by altering the values of L ∗ (brightness), it was also seen that according to the NBS criterion, the value of Δ E was 1.15, which meant a change in color was not perceived by the human eye. This change in luminosity probably occurred due to the presence of abrasive contents in this dentifrice, such as hydrated silica.

The four studies that used the VITA shade guide observed a statistically significant difference between the test and control groups. These favorable findings may have been attributed to the method used to analyze the color on the total surface of the tooth, without taking into account specific points [ 14 ].

The limitations of the present systematic review include the following: the lack of clinical studies using the same method to evaluate the color of dental substrates, in order to allow a comparison of the parameters included in the data analysis; the lack of studies that took into account the durability of color change following discontinuation of the bleaching dentifrices; and the studies did not take into account the frequency of brushing with bleaching dentifrices, as brushing time can influence color change . [ 7 ]. Thus, future studies are necessary in order to investigate characteristics such as morphological alterations of the dental surface caused by dentifrice materials, in order to establish an effective time-of-use protocol, the influence of dentifrice components on whitening properties, and the durability of tooth whitening after whitening toothpaste is discontinued.

5. Conclusions

Within the limitations of this study, the evidence from this systematic review suggested that bleaching dentifrices have potential in tooth whitening. However, these results should be interpreted with caution before any decision is made, and more randomized clinical trials are required to better determine the efficacy of bleaching dentifrices due to their possible morphological alterations of dental tissues.

Conflicts of Interest

The authors declare that there are no conflicts of interest regarding the publication of this paper.

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'If You Can Keep It': Donald Trump, White Evangelicals, And The 2024 Election

Republican presidential candidate former U.S. President Donald Trump speaks at the Faith and Freedom Road to Majority conference at the Washington Hilton in Washington, DC. Drew Angerer/Getty Images hide caption

Republican presidential candidate former U.S. President Donald Trump speaks at the Faith and Freedom Road to Majority conference at the Washington Hilton in Washington, DC.

With his several divorces, violent rhetoric, and long list of criminal charges, former President Donald Trump may not be your idea of a God-fearing Christian. But that hasn't stopped him from appealing to his Christian base.

Roughly 8 out of 10 white Evangelicals supported Trump in the 2016 general presidential election. And a recent Pew Research survey found that among religious groups, white Evangelical Protestants had a more positive opinion of Trump than any other group, whereas the majority of Jewish Americans, Black protestants, and atheists all had an unfavorable opinion of Trump.

Despite their outsized political power, the white Evangelical church is shrinking. According to the Public Religion Research Institute, about 14 percent of the population identifies as white and evangelical. That's compared 25 percent in the 1990s.

Today, we focus on white Evangelical Christians and the effect they will have on the 2024 election.

Find more of our programs online . Listen to 1A sponsor-free by signing up for 1A+ at plus.npr.org/the1a .

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