The science is clear: processed foods are detrimental to our health. Now, a new article in the April 2020 issue of Scientific American suggests that processed foods may undermine our health in ways we may not have previously considered, particularly our oral health.(1)
Teenagers and early adults regularly visit the dentist for removal of their third molars—often referred to as wisdom teeth. Before this rite of passage, teens and smaller children undergo regular dental visits to fill cavities, remove calculus (tartar,) and, at a minimum, endure a thorough cleaning and polishing.
Paleontologist and dental anthropologist Peter Ungar of the University of Arkansas says we have lost our way when it comes to dental hygiene and health.
“Most other vertebrate creatures do not have the same dental problems that we do,” Ungar says. “They rarely have crooked teeth or cavities. Our fossil forebears did not have impacted wisdom teeth, and few appear to have gum disease.”
Dr. Ungar attributes these maladies to the softer and more sugary foods that we eat almost from birth. Strained peas and apple sauce are poor substitutes for our ancestral diets. Instead, he argues, eating foods that are much less processed cause our jaws and teeth to grow strong, straight, and align properly—to an extent that allows enough space for all 32 of our teeth. Mechanical stress of our growing jaws is key to oral health.
He also argues that the move away from ancestral diets has led to tooth decay—primarily exacerbated by high sugar content in processed foods, and the subsequent shift in the mouth’s bacterial biome. His view is supported by the work of Dr. Loren Cordain (2),(3) and others associated with The Paleo Diet®.(4)
For example, Cordain notes, and Ungar supports the observation, that across the animal kingdom, dental problems are not the norm. Humans that pre-date terrestrial agriculture show few signs of dental problems, as is the case with small, isolated human populations today that retain hunting and gathering for food, with no access to westernized foods.
More recently, the biggest jump in problems occurred during the Industrial Revolution, when access to highly refined foods and sucrose became the norm. Soft, sugary foods tipped the balance of oral health to disaster.
Tooth enamel is one of the hardest natural substances. Enamel is underlain by a tough but relatively flexible layer of dentin. Ungar emphasizes that we emerge at birth genetically preprogrammed to mechanically stress our teeth and jaws rather forcefully. Minimally processed foods that require vigorous chewing allow this natural process of oral stress to occur, much to a person’s oral well-being.
Ungar cited work by Robert Corruccini of Southern Illinois University. Corruccini, in a conversation with one of his students from nearby rural Kentucky, was surprised to learn that senior citizens in the student’s community had remarkably high oral health. A follow-up study by Corruccini showed the seniors had better bites than their younger children and grandchildren. The difference? Lifelong experience with lightly processed, hard-to-chew foods.
The moral here is clear. Dental health professionals need to incorporate an evolutionary perspective in their overall strategies for oral health.
- Ungar, P.S. 2020. The trouble with teeth. Scientific American 322(4):45-49.
- Cordain L., Eaton S.B., Sebastian A., Mann N., Lindeberg S., Watkins B.A., et al. 2005. Origin and evolution of Western diet: health implications for the 21st century. American Journal of Clinical Nutrition 81:341–54. https://academic.oup.com/ajcn/article/81/2/341/4607411
- Cordain, L. 2011. The paleo diet: lose weight and get healthy by eating the foods you were designed to eat. John Wiley and Sons, New York. 266pp.
- Vuolo, S. 2016. Tooth decay and the paleo child. The Paleo Diet Newsletter. https://thepaleodiet.com/tooth-decay-and-the-paleo-child/