Mummies and Mouths

by Jason Jones

Way back in grade school, you may recall learning about mummies and how some kids were afraid they would come to life to chase people! But then you learned about the mummification process and how the tissue remains, versus what happens when a body is buried in the earth. It was interesting to learn how the majority of tissue remains intact in the mummy over hundreds of years, whereas with a buried body, just a few months later, only a skeleton is left. This “tissue preservation” can also be seen in bodies found deeply frozen in ice or buried in hot sand. Why does this happen?

After learning about cellular/molecular biology, organic chemistry, effects of pH, etc., the explanation is due to a few factors: energy depletion, dyshomeostasis, molecular breakdown, autolysis, followed by putrefaction (the breakdown by bacteria).

Going back to the mummy and tissue preservation, the bacteria that cause the breakdown process are halted with the use of salts, just as bodies are preserved by freezing in the ice example and by desiccation in the sand scenario. But why would a dentist even mention this? The same process occurs in the mouth! Bacteria cover the inner cheeks, gums, tongue and teeth. The oral cavity also contains good and bad bacteria, and it’s the latter that cause cavities, gingivitis, tooth infections and periodontal disease. At elevated levels, the bad bacteria can also travel into the blood stream and contribute to heart disease, diabetes and stroke, and recently bad bacteria have been found to increase the chance of breast cancer.

What accelerates the bacteria in the mouth is the pH level. It becomes complex and difficult to describe, so the easier way is saying “sugar causes cavities.” In reality, the sugar (carbohydrates) gets broken down by the bad bacteria on your teeth and leaves acid. In technical terms, the pH decreases (becomes acidic) and results in demineralization of the tooth enamel (dissolves the tooth), which eventually spreads and becomes a hole in the tooth, aka a cavity.

The pH scale ranges from 0 to 14, with 0 being most acidic and 14 being most alkaline. The pH of pure water is in the middle at 7; the blood in our body normally functions within 7.35 to 7.45. Our mouths when not exposed to any foods can range from 6.3 to 7.6 depending on the saliva and bacterial levels in your mouth. Everyone has different pH levels and different populations of bacteria in their mouth. The more bad bacteria you have in your mouth, the more acidic it becomes. When the pH level drops below 5.5, the tooth starts to break down. This is what we call the critical pH. The food we eat can be acidic or alkaline, and even healthy foods can be really acidic. For example, the pH of a lemon is at 2.0, cranberry juice 2.5, broccoli 6.0, to name a few.

Let’s say your mouth is at a pH of 6.5 and you sip a bottle of cranberry juice slowly over a course of two hours. Each sip drops the pH down to 2.5 and will take 30 minutes for the saliva to bring it back to the original 6.5. If you take a sip every 10 to 15 minutes, it doesn’t get the chance to go back to 6.5. The pH will remain below the critical pH for the entire two hours of sipping the drink plus 30 minutes of saliva bringing it back. Having the teeth bathing in an acidic state for 2.5 hours now has increased the chance of developing cavities. On the other hand, if you were to drink the entire bottle within a five-minute period, the exposure time would be cut down to 35 minutes. Thirty-five minutes of acid on the tooth sounds much better than 2.5 hours, and yet the diet stayed the same.

Similarly, in bone, a decrease in blood pH can change the way our bone remodels, resulting in higher resorption (low density). Recent studies also show that acidic levels can be responsible for an increase in Type 2 diabetes, heart disease and obesity. You may have heard of alkaline diets and supplements to help your blood become more alkaline, and these are some of the many reasons to lean toward an alkaline diet. Talk with your dentist about managing the oral cavity and get in touch with a nutritionist or wellness dietician to develop an alkaline meal plan that best suits you.