Do you avoid mouthwash or toothpastes with glycerine? Many people do, particularly those who opt for natural toothpaste. There are many misconceptions around this ingredient, and we've taken an in-depth look into the all the scientific research behind its effects in oral care. 

Does glycerine coat your teeth?

This misconception has been widely spread. It originates from a self-published book by a chemist called Gerard. F. Judd. Although the claim seems to relate to sucrose, as opposed to glycerine, the idea seems to have been taken up by many practitioners of holistic dentistry. It’s worth pointing out that Judd relies on his own experiments as evidence for this and that the paper is not peer-reviewed. 

Glycerine is highly water-soluble, so any residue left can easily be dissolved by saliva. The brushing action and other ingredients in toothpaste will also play a part in removing any residue, meaning it won’t leave a coating on the teeth. 

Does glycerin prevent remineralisation?

This is actually partly to do with the above misconception. The theory is that it coats the teeth in a film, therefore preventing remineralisation. You can find this claim on many natural health sites although, again there is really no science beyond the home experiment of Gerard F Judd.

In her 2020 blog about glycerine, researcher Emilee Kendell suggests that it is better to avoid proven harmful substances, such as SLS or titanium dioxide, in your toothpaste. 

There have been various studies on products containing glycerine to be effective in remineralising teeth. 

Is glycerine is bad for teeth?

Glycerine is often confused with glucose, sucrose and occasionally fructose. These do not damage teeth as such, but bacteria in the mouth can feed on them and produce acids that can erode enamel. Glycerine, although having the sweet taste of glucose, etc. actually contains antimicrobial and antiviral properties which kill bacteria in the mouth. 

Glycerine is also used as a treatment for dry mouth, a condition that can lead to oral health concerns. Our saliva acts to protect our teeth from bacteria, supporting the oral microbiome and prevent decay. Glycerine, as a humectant, helps to retain moisture in our mouths. 

Is glycerine is a by-product of soap 

Nope, although it can be used in soap, skin and hair care products for texture and benefits to the skin. Fun fact: in the 1800s, glycerine used to be used in dynamite! Vegetable glycerine is made by applying heat to plants rich in triglyceride-rich vegetable fats  (fats that our body stores for energy). The glycerine separates from the fatty acids leaving the sweet-tasting odourless liquid.

Is glycerine is made from GMO fruits and vegetables?

It depends very much on which product you are using and who it’s made by.  Organic glycerine made from rapeseed oil is widely available. So soil health, biodiversity and water are all taken into consideration in its production process. 

Is glycerine vegan?

It’s important to check the ingredients to find what the glycerine is derived from. Some can be made from either palm oil or soy, or even animal fats. 

Should you avoid glycerine in toothpaste? 

The scientific research is ongoing but at this stage, it looks as though the benefits outweigh any negatives. In fact, many researchers go as far as to suggest that the claim that glycerine coats the teeth and prevents remineralisation has no actual scientific evidence.

Did you know…?

At Truthpaste, we have always sought to find the most sustainable and eco-friendly alternative to any harmful chemical ingredients.

We thoroughly research all ingredients for its health benefits or risks before deciding to use it, making sure it aligns with our pledges.

Sources 

Nelson, D. L.; Cox, M. M. (2000). Lehninger, Principles of Biochemistry (3rd ed.). New York: Worth Publishing

Yeliz Guven, Nilufer Ustun, Elif Bahar Tuna, and Oya Aktoren (2019): Antimicrobial Effect of Newly Formulated Toothpastes and a Mouthrinse on Specific Microorganisms: An In Vitro Study, European Journal of dentistry

Emilee Kendell, (March 2020)  ASK MERCURIAL: DOES GLYCERIN IN TOOTHPASTE PREVENT REMINERALIZATION?,  A Mercurial Consciousness

Administration, (2019), Pros and Cons of Glycerine for oral hygiene, Affinity Dental

Gary M. Virigin, (2018), No, Glycerin Isn’t a Problem for Tooth Remineralization, Biologicaldentalhealth.com

Kinnunen T, Koskela M. Antibacterial and antifungal properties of propylene glycol, hexylene glycol and 1,3-butylene glycol in vitro. Acta Derm Venereol. 1991; 71:148- 150.