Modern Food Reduced Diversity of Oral Bacteria

A new paper in Nature Genetics describes research into the bacteria in ancient teeth plaque. When modern food came along, the bacteria became less diverse. One of the researchers said:

The composition of oral bacteria changed markedly with the introduction of farming, and again around 150 years ago. With the introduction of processed sugar and flour in the Industrial Revolution, we can see a dramatically decreased diversity in our oral bacteria, allowing domination by caries-causing strains.

Whether the decrease in diversity was due to (a) more sugar and flour or (b) less bacteria-laden foods is hard to say.

Again, data suggest we need bacteria to protect us against bacteria. You’d never know this from food safety laws or how freely pediatricians prescribe antibiotics. Again, it is hard to know without more research what caused this or that historical change in health (e.g., more tooth decay when sugar and flour became popular). The obvious answer (e.g., sugar causes tooth decay) might be wrong. If you believe that cavities are caused by too much sugar, the solution is to eat less sugar. What if cavities are caused by not enough bacterial diversity? Then other solutions might work better, such as eating more fermented food.

Thanks to Vic Sarjoo.

3 Responses to “Modern Food Reduced Diversity of Oral Bacteria”

  1. Ahrand Says:

    I have found that instead of combating bacteria in your mouth (flossing, brushing, rinsing with anti-bacterials), it is more helpful to gently guide them to behave and force them to diversify.
    I use Xylitol (a non-fermentable sugar) after meals and before bed, it is difficult to digest for (certain) bacteria so they cause less problems (the population adapts but seems to be less virulent).
    Trying to wipe out all bacteria never works as there are always means/places for them to hide and come back (stronger) after the anti-bacterials have flushed.

    Surprising results after 2 years: whiter teeth, less dental plaque, less sinus infections, …

  2. Evelyn M. Says:

    Thank you, Ahrand, for your post. I, too, am convinced that xylitol is an unmitigated blessing. I suffered from terrible oral lichen planus that medical science could do nothing about. A desperate web search convinced me to try xylitol. A half-teaspoon three to four times a day after eating within three months showed that the lichen planus was receding, and after six months it was clearly in remission. My dentist was astounded. My mouth has never been in better shape – even the “geographic tongue” that I had since adolescence is gone – and at basically no cost using a substance that anyone can buy off the web. Read the literature, especially from Finland, where they have done many clinical trials on children.

    Seth: That’s fascinating. Good work!

  3. Paul N Says:

    Certainlu hard to separate the causes (sugar v bacteria) especially since they are related. Eating sugar encourages the growth of sugar loving bacteria, regardless of what other bacteria are eaten. Weston Price concluded that the “displacing foods of modern commerce” – sugar and white flour – were the primary cause. Not only do they make the problem worse, they displace other foods, often fermented ones, so both causes are in operation.

    Incidentally, in Jared Diamond’s “Collapse” he talks about some pacific island where sugar cane naturally grew, and the islanders squeezed the juice, as a source of fresh water. Not surprisingly, their teeth had lots of cavities, and old skulls showed the same.

    We should also keep in mind that various vitamins, particularly D, K2, C and various minerals (calcium, magnesium, phopshorous) contribute to dental health. A diet deficient in these could still have dental problems even with low sugar and high good bacteria. Indeed, even Weston Price wrote about this, and found that places with naturally high fluorine in the water had lower rates of dental decay.

    I would posit that neither the absence of sugar nor the presence of beneficial bacteria alone, is sufficient to ensure optimal dental health, though they are unquestionably major factors.

    Seth: I agree. I found that my gums became much healthier when I started drinking flaxseed oil. It is quite possible that the traditional diets of Weston Price, not just the modern ones, had too little omega-3.