Natural Teeth Whitening: What Works And What Doesn't

Natural teeth whitening covers kitchen remedies, and this guide takes five of them: baking soda, activated charcoal, oil pulling, strawberries and lemon. By mechanism, baking soda is an abrasive that can scrub off some of the stain built up on the outside of a tooth, charcoal is also used as a scrub, oil pulling is a rinse, and strawberries and lemon bring acid. None of the five is a bleaching agent, so none of them lightens the colour of the tooth itself. The American Dental Association's summary of the whole group is that "The limited studies to date on DIY or natural whitening interventions raise questions regarding the efficacy and safety of these approaches."

Below, each remedy in turn, with what named sources say about abrasion and acid, then the honest answer to how to whiten teeth naturally at home, and what to look at if "natural" really means "no peroxide" to you.

How the colour of a tooth can change

Two kinds of colour are involved, and the American Dental Association (ADA) separates them. "Extrinsic stains commonly result from an accumulation of colored compounds on enamel", while "Intrinsic stains occur inside the tooth (within the enamel or the underlying dentin)". Underneath the enamel sits dentine, which is yellower, and our guide to why teeth look yellow goes through how the two layers combine.

There are two ways to change what you see. You can scrub off what has built up on the outside, which is abrasion. Or you can act on the coloured compounds chemically, which is bleaching. The ADA describes it like this: "The bleaching process is generally believed to occur when reactive oxygen molecules (generated from hydrogen peroxide) interact with organic chromophores (colored compounds) within enamel and dentin through a chemical oxidation process". None of the five remedies below works that way.

What the ADA says about natural and DIY whitening

The ADA's professional page on whitening has a section on do-it-yourself whitening. It covers "use of acid-containing fruits, vinegar or products containing charcoal and the practice of swishing coconut oil in the mouth (known as oil pulling)", and its conclusion is the line quoted at the top of this page.

The ADA's consumer site, MouthHealthy, has a page on natural whitening that makes a related point: "just because a method is natural doesn’t mean it’s healthy." The ADA is a United States body.

Baking soda

Baking soda, or bicarbonate of soda, is an abrasive. MouthHealthy calls it "something that is abrasive (like baking soda)". Brushed on, it can scrub off some of the stain that has built up on the enamel. It is not an oxidising agent, so it does nothing to the coloured compounds inside the tooth.

The published review on baking soda is about toothpastes that contain it, not about a paste mixed at the sink. We have gone through that review, and what abrasion does to a tooth, in our post on whether whitening powder works, so it is not repeated here.

MouthHealthy also warns that "using materials that are too abrasive on your teeth can actually make them look more yellow." Its reason is that a scrub which is too rough can wear enamel away and expose the softer, yellow dentine underneath.

Some recipes add hydrogen peroxide, and MouthHealthy names "a baking soda-hydrogen peroxide paste" among the scrubs it covers. That is a different thing: the peroxide, not the soda, is the bleaching agent. What it does to teeth, and the UK limits on it, are in our post on hydrogen peroxide on teeth.

Activated charcoal

Charcoal is sold as toothpaste, powder and more, and when it is brushed on it works as a scrub. It carries no bleaching agent of its own.

The ADA's professional page is direct about the evidence: "to date there is insufficient evidence demonstrating that charcoal-based oral care products or modalities provide measurable benefit in whitening vital teeth with adequate safety and effectiveness." MouthHealthy cites the September 2017 issue of the Journal of the American Dental Association for the same point. The charcoal review in that issue is the one our powder post covers.

The ADA also cites a 1990 report on dental abrasion in a group of people in Malaysia, in which, in the ADA's words, "a mixture of charcoal and table salt was abrasive and ineffective". The teeth had a yellow cast, which the report's authors put down to enamel being brushed away so that the dentine showed through, and the ADA adds that "the report documented deep concave abrasion cavities on labial surfaces of the anterior teeth following use." That is one report about one homemade mixture, not a test of charcoal products in general.

Oil pulling

Oil pulling means swishing an oil, such as coconut oil, around the mouth and then spitting it out. It is neither a scrub nor a bleaching agent, so there is no obvious route by which it could change the colour of a tooth.

The ADA's professional page notes "an absence of documented tooth whitening derived from oil pulling, which has also been associated with adverse events ranging from lipoid pneumonia to upset stomach and diarrhea." MouthHealthy puts it more simply: "There is no reliable scientific evidence to show oil pulling or turmeric whitens teeth."

Strawberries

The strawberry idea rests on malic acid. A 2015 laboratory study in the journal Operative Dentistry, by Kwon, Meharry, Oyoyo and Li, set out the background plainly: "The advocated use of fruits such as strawberries and apples is based solely on anecdotal evidence with the rationale that they contain malic acid."

They tested it on 120 extracted human molars in six groups. The do-it-yourself group had a strawberry purée mixed with baking soda left on for five minutes, then brushed for 30 seconds, three times at five-day intervals. Three groups had conventional peroxide whitening (in-office, a dentist-dispensed home gel and an over-the-counter product), and two controls were treated with water and with 1% citric acid.

"At three months, NC, DIY, and PC showed an overall color change of 2.3, 2.4, and 2.53, respectively, which is less than the perceptibility threshold of ΔE 2.6 units." NC is the water control and PC the citric acid control, so the strawberry and baking soda teeth changed about as much as teeth kept in water, and below the perceptibility threshold the authors cite. Their conclusion: "DIY whitening with the use of a strawberry mixture is not an effective tooth whitening modality when compared to professionally applied in-office whitening, professionally dispensed patient-applied home whitening, and an OTC product."

The study did not test lemon, but its citric acid control bears on it. The authors wrote that "DIY whitening with strawberries as well as the positive control group using 1.0% citric acid was not effective in whitening, which showed that color change is not due to the acid component in fruits."

The limits are the authors' own: "The result of this study is partially limited by the use of extracted human teeth, which will inherently differ from vital teeth in the oral environment." It is also one test of one recipe. The authors declare no interest in any product in the paper, and the article page carries no funding statement.

Strawberries are acidic as well. The Oral Health Foundation lists "Berries (such as strawberries and raspberries)" among acidic foods, which is what the next section is about.

Lemon, and vinegar

Lemon brings acid, and acid acts on enamel rather than on stain. The Oral Health Foundation, the UK oral health charity, explains: "Every time you eat or drink something acidic, your tooth enamel softens temporarily." It lists "Citrus fruits (oranges, lemons, limes, grapefruit)", "Lemon water or hot water with lemon" and "Vinegar and foods pickled in vinegar" among acidic foods and drinks. When enamel wears away, it says, "Teeth may look thinner or more yellow." It also says that brushing during the softened stage can "Remove tiny amounts of enamel."

Bupa Dental Care's page on tooth erosion, clinically reviewed by Dr Gurmandeep Sond, former Clinical Development Manager at Bupa Dental Care, and last reviewed on 30 September 2024, lists "citrus fruits, like lemons and oranges" and "vinegary foods, like dressings and pickles" among the causes. Among the signs, it says you might notice "your teeth look darker or yellow, because the dentine is showing".

MouthHealthy is careful to separate eating fruit from scrubbing with it: "When eaten as usual, fruit is a great choice." Its concern is what happens when you "prolong their contact with your teeth or use them to scrub your teeth because acid can wear away your enamel." It names apple cider vinegar in the same group.

So for lemon the mechanism runs the wrong way. In the 2015 study, a 1% citric acid solution did not whiten extracted teeth, and in the Oral Health Foundation's and Bupa's descriptions, the result of enamel wearing away is a tooth that can look more yellow, not less.

So how can you whiten teeth naturally at home?

None of the five remedies above can bleach your teeth. What a natural routine can do is keep new stain from building up, with the existing build-up cleaned off at the dentist. MouthHealthy's list of "The best natural ways to keep your teeth white" is a list of everyday habits, including brushing twice a day for two minutes, cleaning between your teeth once a day, "Limiting foods that stain your teeth, like coffee, tea and red wine", not smoking or using tobacco, and regular visits to the dentist for check-ups and cleanings.

For acid, Bupa's erosion page adds two lines worth knowing: "After having acidic foods or drinks, wait an hour before brushing your teeth to avoid further damage." and "Brush your teeth gently with a fluoride toothpaste twice a day."

Those are the sources' recommendations rather than ours, and apart from the professional cleaning they keep stain down rather than lift what is already there. For stain that has built up, each type of stain and the option that reaches it is set out in our guide to removing stains at home. A change in the shade of the tooth itself takes a whitening agent, and none of the five remedies is one.

If "natural" means "no peroxide" to you

If "natural" is shorthand for avoiding peroxide rather than for using kitchen ingredients, that is a separate question with a separate answer. Our peroxide-free whitening strips use PAP, short for phthalimidoperoxycaproic acid. We do not describe PAP as natural, and it is not a kitchen ingredient. It is peroxide free, and it still works on the coloured compounds inside the tooth, just by a gentler route than peroxide takes. That is the difference from the five remedies above, and how PAP whitening works explains the chemistry.

Peroxide is part of the Pure Glow story too. Daniel, the founder, was working a three-shift pattern, drinking a lot of coffee and smoking at the time when he noticed his teeth staining. Peroxide strips caused bad sensitivity and made his teeth feel brittle, and the non-peroxide ones he tried would not stick, slid around, gave patchy results and left gunk behind. If sensitivity is what has put you off whitening, there is a separate page on strips for sensitive teeth.

Our 28 strip box is a 14-day course, one treatment a day, upper and lower, each worn for a minimum of 30 minutes. The formula also carries hydroxyapatite, which supports the enamel surface, and there is more on our whitening strips with hydroxyapatite page. The claim on the box is a ceiling: up to 6 shades whiter in 14 days, depending on where you start. What the strips will not do is re-colour a composite, a crown or a veneer, although stain that has built up on top of dental work can lift.

Frequently asked questions

Does baking soda whiten teeth?
It can scrub off some stain built up on the enamel, because it is an abrasive, but it is not a bleaching agent, so the colour of the tooth itself stays the same. In the 2015 laboratory study, a strawberry and baking soda mixture changed tooth colour about as much as plain water did. The evidence for baking soda is about toothpastes that contain it, which our powder post covers.

Does activated charcoal whiten teeth?
The ADA says there is insufficient evidence that charcoal-based oral care products provide measurable benefit in whitening teeth with adequate safety and effectiveness. Brushed on, charcoal works as a scrub.

Does oil pulling whiten teeth?
The ADA's MouthHealthy site says there is no reliable scientific evidence that it does, and its professional page notes an absence of documented whitening from oil pulling.

Do strawberries whiten teeth?
In the 2015 laboratory study, a strawberry and baking soda mixture made no perceptible difference to extracted teeth after three months. Strawberries are also on the Oral Health Foundation's list of acidic foods.

Does lemon juice whiten teeth?
The 2015 study did not test lemon juice, and its 1% citric acid control did not whiten extracted teeth. Lemon is acidic, the Oral Health Foundation says acid softens enamel temporarily, and Bupa says tooth erosion can leave teeth looking darker or yellow because the dentine is showing.

Does apple cider vinegar whiten teeth?
MouthHealthy groups it with lemons and oranges as a naturally acidic household staple, and the Oral Health Foundation lists vinegar among acidic foods, so the lemon answer applies.

Does turmeric whiten teeth?
MouthHealthy says there is no reliable scientific evidence that turmeric whitens teeth.

Is natural teeth whitening safe?
We would rather let the sources answer that than give a verdict of our own. The ADA says the limited studies on DIY and natural whitening "raise questions regarding the efficacy and safety of these approaches", the Oral Health Foundation and Bupa both describe acid as a cause of enamel wear, and Bupa lists brushing too hard among the other causes.

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Related reading:

• Teeth whitening at home
• Coffee and tea stains on teeth
• Your teeth whitening options

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Sources:

• American Dental Association, Oral Health Topics: Whitening, last updated 16 August 2022. ada.org. A United States source.
• American Dental Association, MouthHealthy, Natural Teeth Whitening: Fact vs. Fiction (undated). mouthhealthy.org. The ADA's consumer site. A United States source.
• Kwon SR, Meharry M, Oyoyo U, Li Y. Efficacy of Do-It-Yourself Whitening as Compared to Conventional Tooth Whitening Modalities: An In Vitro Study. Operative Dentistry 2015;40(1):E21-E27. doi 10.2341/13-333-LR. A laboratory study on extracted human teeth.
• Oral Health Foundation, Dental erosion, last reviewed 24 March 2026. dentalhealth.org
• Bupa Dental Care, Tooth erosion, clinical review by Dr Gurmandeep Sond, former Clinical Development Manager at Bupa Dental Care, content review by Michelle Harrison, last reviewed 30 September 2024. bupa.co.uk