Many parents and dental professionals are beginning to question the benefits milk has on teeth and particularly those of growing children. We have been taught for decades that there is nothing better for our teeth, bones and overall health than the white stuff; however, certain negative factors are now being brought to light. Milk sugar is considered as a contributory factor towards development of tooth decay. Recent studies have also linked milk consumption to excessive mucus production, which may indirectly lead to chemical erosion of teeth.
Milk sugar (lactase) is usually the most discussed issue when it comes to the primary contributory factor toward tooth decay but, more recently, other evidence relating to the indirect effects milk has on teeth have started to surface.
The belief that milk can often cause an increase in mucus production has been under discussion for a long time. In some cultures though, and particularly in Asian treatments such as Total Chinese Medicine, associations between milk and mucus have long since been considered a normal diagnosis. Now though, similar issues are beginning to be acknowledged by western science.
When breathing is adversely affected by an increase in mucus this makes sleeping with your mouth closed very difficult. Aside from the fact that sleeping in this way can affect not only how teeth grow but also face shape, (look out for a forthcoming article discussing how milk and mucus can affect craniofacial features!) a research paper published in 2015 investigated the issues in respect of general oral health (Choi, et al. 2016).
In particular, they looked at the effects of the mouth environment between people who sleep with their mouth closed and those who sleep with their mouth open. What they found was at least one difference which could result in increased dental erosion and which is also indirectly linked to milk consumption.
People who sleep with their mouth open often do so simply because they have an excess amount of mucus which makes it impossible for them to sleep with closed mouth. This habit, although it’s actually a result of nervous system responses, often also corresponds with other symptoms that are linked to asthma type issues. The researchers discovered that when someone sleeps with their mouth open, the pH of the mouth, which starts off as a neutral acid/alkaline balance when we go to sleep, becomes increasingly acidic as the night progresses. This means that people who sleep with their mouth open have a more acidic oral environment during sleeping hours than those who sleep with their mouth closed.
The hypothesis put forward by this study, is that an increase in mucus causes us to sleep with our mouths open resulting in increased acidity within the oral cavity and which can, in turn, contribute to dental erosion and caries.
At least when it comes to children and improving dental health, most parents have a head start – because few are unaware if their child sleeps with mouth open or closed. However, even if you have never seen your child sleep with their mouth open, which in itself is unlikely, other indications of your child being a ‘mouth breather,’ are; waking with a dry mouth which is caused by a reduction in the amount of saliva or, less commonly, discomfort or dryness in the throat which can also be caused by reduced saliva, but also because snoring, another indication, is frequently found in mouth breathers.
The clues then for most parents are clear; If your child is prone to suffering from tooth erosion and also suffers from excess mucus, has a tendency to sleep with their mouth open and quite likely is prone to snoring and waking with a dry mouth, all the problems might well be reduced simply by restricting milk consumption.
Health. Lifestyle. Laughter
Choi, J. E., J. N. Waddell, K. M. Lyons, and J. A. Kieser. “Intraoral pH and temperature during sleep with and without mouth breathing.” Journal of Oral Rehabilitation 43, no. 5 (May 2016): 356-363.