Is Hydrogen Peroxide Safe for Teeth Whitening?

Is Hydrogen Peroxide Safe for Teeth Whitening?-Bliss Oral Care

What is hydrogen peroxide? We all recognize it when we see it. Hydrogen peroxide is usually supplied in plain brown plastic bottles - which is great marketing in itself, as we can all instantly pick it out on any crowded shelf.

We all recognise it when we hear about it. Hydrogen peroxide is a common household item that we all keep in our cabinets. It has been used safely for almost 70 years. Its uses vary, as it is used medicinally to clean wounds, sanitarily to disinfect surfaces around the house, cosmetically to bleach hair, and yes - even to whiten teeth.

“Over the years (and before social media trends), hydrogen peroxide has been a safe way to whiten teeth at home. 3% concentration, in particular, is a safe, easy, and cheap option for home use and can provide results when used over time.”

Dr. Peter Guirguis, DDS, Owner of Definitive Dental

How Does Hydrogen Peroxide Work?

Hydrogen peroxide (H2O2) is a chemical mixture of hydrogen and oxygen that oxidizes the second it is exposed to air. This oxidation process is what makes hydrogen peroxide such an effective disinfectant. H2O2 kills bacteria easily by contact. Being able to simply wipe dirty surfaces down has ingrained hydrogen peroxide as a household cleaning staple because of this. So does hydrogen peroxide work on whitening teeth?

How Does Hydrogen Peroxide Make Your Teeth White?

When used safely, hydrogen peroxide will whiten teeth over time. A study has shown that H2O2 does indeed whiten the teeth in conjunction with the correct formula of hydrogen peroxide concentration + time that it is applied to the teeth.  

Most at home teeth whitening solutions today use hydrogen peroxide as their active teeth whitening ingredient. It is usually found in a gel form - which maximises the amount of time the H2O2 can kill bacteria and lift off any discolouration from the enamel on our teeth.  

Can I just swish hydrogen peroxide in my mouth to whiten teeth?  

Using the liquid form, found in the brown bottle on the shelf, would simply not allow enough time for the hydrogen peroxide to work. Simply swishing it makes the H2O2 to break down too quickly to have any positive whitening effects. Although it would help in killing a lot of the stubborn bacteria that loves to hang out in our mouths.  

Is it Bad to Whiten Your Teeth with Hydrogen Peroxide?

No. Hydrogen peroxide, when used correctly, is perfectly safe for teeth whitening. 3%-6% dilution is considered safe to use as a base line. Most teeth whitening products use the 3% dilution strength as a starting point with specific instructions on how often and how long the products should be applied to the teeth.  

The importance of following instructions cannot be overstated. Our teeth are unique and react differently to certain treatments. Applying weaker H2O2 concentration over shorter periods of time has shown the best results for teeth whitening. We should never look for instant results when considering either professional or at home teeth whitening procedures.

Are there any Negative Side Effects of Using Hydrogen Peroxide on Teeth?

Always follow instructions! Most rarely reported teeth and gum damage that does occur, happens only when teeth whitening products  are used without adhering to the instructions. 

There can be minor irritation to the gums and heightened sensitivity in the teeth as the layer of enamel can be worn away with over exposure to hydrogen peroxide. This is again usually caused by not following instructions prior to use, or simply, by overuse of teeth whitening products.   

How Long Does it Take to See Results with Hydrogen Peroxide on Teeth?

Professional teeth cleaning uses up to a 40% hydrogen peroxide concentration.  Results of this highly expensive cosmetic procedure vary. Some see immediate results while others say it took over 4 weeks to see any results.  Ironically enough, most complaints about hydrogen peroxide teeth whitening are recorded after this highly potent exposure to H2O2 from professional whitening.

It is much safer to whiten teeth through lower hydrogen peroxide levels over longer periods of time. One can equate it to dieting or working out. One should never expect instant results. The best long lasting results are always found via patience, a daily application routine, and following a strict regimen. As with working out and dieting, results will vary with using hydrogen peroxide to whiten teeth, but the average study shows positive results in 2-3 weeks.  

Should I Use Teeth Whitening Products that use Hydrogen Peroxide?

Yes! Using our examples again of dieting and working out, eating healthier, exercising, and keeping our teeth cleaner and healthier will have positive results. Using teeth whitening products that contain H2O2 of course goes hand in hand with basic oral hygiene rules. Always brush and floss. Avoid certain foods that stain the teeth. Visit your dentist for regular check ups.

There are many other online at home teeth whitening procedures that do not involve the use of hydrogen peroxide. Oil pulling and rubbing down your teeth with fruit or vegetable peels can be helpful, but are nowhere near as consistent and professionally-approved as viable ways in which to quickly whiten your teeth.


Teeth whitening products using hydrogen peroxide as their active bleaching ingredient are perfectly safe to use. They can and will lighten and whiten teeth if used correctly. 

This conclusion is stated assuming one is using the product while strictly following the instructions provided.