Baking soda can help remove surface stains from teeth and is surprisingly gentle, with a low abrasivity score. What it cannot do is bleach the deeper colour of a tooth. So it may make teeth look cleaner and a shade brighter by lifting stains, but it will not change your natural tooth colour the way a bleaching treatment does.
Key takeaways
- Baking soda works by mild abrasion, gently scrubbing away surface (extrinsic) stains from coffee, tea, and similar.
- It does not contain a bleaching agent, so it cannot lighten the intrinsic colour of teeth.
- On its own, pure baking soda has a very low abrasivity (an RDA of around 7). Toothpastes containing baking soda typically sit between about 35 and 134, well within the safe limit of 250.
- A baking soda toothpaste that also contains fluoride is a better everyday choice than homemade paste, which offers no fluoride protection.
How baking soda works on teeth
Baking soda (sodium bicarbonate) is a fine powder that dissolves easily in water. When used on teeth it acts as a mild abrasive, physically loosening the film of stain that builds up on the enamel surface. It is also mildly alkaline, which can help neutralise acid in the mouth. Research published in the Journal of the American Dental Association has found that baking soda dentifrices are effective and safe for removing stains, and are often better at it than some non-baking-soda toothpastes that are actually more abrasive.
Surface stain versus deep colour
Understanding the two kinds of tooth discolouration explains what baking soda can and cannot do.
| Type of discolouration | Cause | Does baking soda help? |
|---|---|---|
| Extrinsic (surface) stain | Coffee, tea, red wine, tobacco | Yes, it lifts surface stain |
| Intrinsic (internal) colour | Natural tooth colour, ageing, some medications | No, it cannot bleach internal colour |
If your teeth are stained mainly from food and drink, baking soda can help them look cleaner. If you want to lighten the natural shade of your teeth, that needs a bleaching product, which works chemically rather than by scrubbing. Our guide on professional versus at-home whitening explains those options, and what causes coffee, wine, and tea staining covers the stains baking soda targets.
Is baking soda safe for enamel?
Abrasivity of toothpaste is measured on a scale called RDA (relative dentin abrasion), and the internationally accepted safe limit is 250. Pure baking soda sits very low on this scale, at around 7, which makes it one of the gentler options. Interestingly, because baking soda dissolves so readily, adding it to a toothpaste tends to lower the overall abrasivity rather than raise it. So the common worry that baking soda is harsh on enamel is largely a myth when it is used sensibly.
The bigger risk comes from how it is used. Scrubbing hard with a homemade gritty paste every day, or using it with an acidic ingredient like lemon juice, can wear enamel over time. Our guide on whether whitening damages enamel covers this in more detail.
How to use baking soda sensibly
- Prefer a commercial baking soda toothpaste with fluoride. You get the stain-lifting benefit plus the decay protection that plain baking soda does not provide.
- Do not use homemade paste every day. Occasional use is fine for most people, but daily hard scrubbing is not necessary and can be rough.
- Never mix it with lemon or other acids. The acid softens enamel and the scrubbing then wears it away.
- Brush gently. Let the product do the work with a soft brush and light pressure.
- Do not expect a colour change. If your goal is a lighter shade, baking soda is not the tool.
How it compares to whitening toothpaste
Most whitening toothpastes also work mainly by removing surface stain rather than bleaching, so baking soda toothpaste is broadly in the same category. Our guide on whether whitening toothpaste actually works explains why. For a genuine change in shade, a supervised bleaching treatment is the reliable route.
Frequently asked questions
Does baking soda actually whiten teeth?
It removes surface stains, which can make teeth look brighter, but it does not bleach the deeper colour. For a real shade change you need a bleaching product.
Will baking soda damage my enamel?
Used sensibly it is one of the gentler options, with a very low abrasivity. Daily hard scrubbing, or mixing it with acids like lemon, is what causes wear.
Can I use baking soda every day?
A baking soda toothpaste with fluoride is fine daily. Homemade paste is better kept occasional and used gently.
Should I mix baking soda with lemon juice?
No. The acid in lemon softens enamel and the scrubbing then wears it away. Avoid this combination.
Is baking soda better than whitening toothpaste?
They work in a similar way, mainly by lifting surface stain. Neither bleaches the internal colour of teeth.
Considering whitening at Lumi Dental
If you want a genuine change in the shade of your teeth rather than just surface stain removal, the team at Lumi Dental can talk through safe, supervised options. You can arrange a complimentary cosmetic consult or read about teeth whitening at Melrose Park to understand what is involved.
