Estimated reading time: 4 minutes

By Alexa Martinelli, DMD

We always talk about the health consequences of consuming dairy, and of course the benefits of switching to plant-based options. We are looking at another aspect of our overall health that is not as often discussed: dental health. Keep reading to learn more about how dairy can affect your oral health.

Cavity Formation

When most people think of cavities, they think of “sugar” causing the cavities. The mechanism of creating a cavity is a more complex process than just sugar entering the mouth and then a cavity appearing. The process begins with sugar entering the oral cavity from the food you drink or eat. Once inside, your mouth’s bacteria eat the sugar and release acid. This release of acid causes the pH of your mouth to drop, creating an environment which starts to dissolve the tooth surface. This dissolution of enamel is the start of the cavity process.(1) For this reason, beverages with sugar like juice and soda are highly likely to cause a cavity– because of the acidic environment which takes hold after drinking them.

Soda and juice are considered “sugar-sweetened beverages” (SSBs) by the USDA, and we are told to reduce them in our diet to prevent dental cavities and reduce our overall added-sugars intake.(2)

Although dairy milk has sugars (mostly lactose) in it, it has not been classified as a “sugar-sweetened beverage” by the USDA nor the American Academy of Pediatric Dentistry. (2,3,4) Furthermore, dairy milk has been said to be “good” for your teeth. If you think about it, it seems contradictory that a drink with sugar would be “good” for your teeth.

(Read the latest research on pediatric dentists’ attitudes towards dairy as a sugar-sweetened beverage.)

Tooth Strength & Dairy Milk

Let’s talk about the reasons why dairy milk has not fallen into the SSB category. In addition to lactose, dairy milk also contains proteins like casein which prevent sugars from sticking to your teeth. For this reason, casein counteracts the negative effects of sugars present in the dairy milk. However, murine models have shown that white milk on its own can cause changes to the enamel.(5) When milk has sugar added to it to make chocolate milk, there is a significant increase in the incidence of cavities compared to white milk.(6) Therefore, not all milk is “safe” for the teeth.

Milk has also been said to be “good” for your teeth since it contains calcium phosphate. Teeth are a hard tissue in the body which means the surface of them can be added to or taken away from.(7) This happens via a process called remineralization, where minerals in a solution re-adhere to the surface of teeth and make them more resistant to decay. The calcium and phosphate in milk exists in a molecule called calcium phosphate which can help remineralize or demineralize the tooth surface.(7) It is correct to say that the high concentration of calcium phosphate in milk decreases its ability to cause a cavity, but the extent to which it makes the tooth stronger only exists on the outermost layer of the tooth. Since tooth calcification is largely finished before a tooth erupts, milk cannot change the innate structure of a tooth.(8) It simply alters the surface of the enamel since human enamel cannot be repaired or reformed.(9,10)

Dental Health

Overall, research supports that fluoridated toothpaste is a proven agent to work against cavities.(10) A simple, unspecialized treatment to regenerate enamel has yet to be discovered.(11) Beyond this, dairy milk also lacks docosahexaenoic acid (DHA) which is crucial to human brain development.(12,13) The digestive process of cows actually removes the DHA from the dairy milk.(14)

Conclusion

To conclude, a beverage like milk which has added sugars and other harmful substances in it should not be considered “good” for your teeth and overall dental health. Water should be your first-choice to prevent cavities and lead a healthy lifestyle.

Huge thank you to Alexa Martinelli, DMD for volunteering her time to contribute this article.