Many anthropologists believe that as humans transitioned from hunting and gathering to farming thousands of years ago, they began suffering from tooth decay and gum disease, prompting some scientists to say that we’d have better oral health with a diet based on wild foods instead of staples like corn and potatoes. Yet today’s Hadza tribe in Tanzania is changing this theory as researchers observe these foragers move to an agricultural diet.
“The Hadza offer us a window into the past and challenges the prevailing assumption that foragers were healthier before they switched to an agricultural diet based on cereals such as corn and wheat,” said Alyssa Crittenden, the Linicy Assistant Professor of Anthropology at the University of Nevada, Las Vegas. “For example, our results show that a person’s sex and where they live really influences how healthy their teeth are.”
“The transition from hunting and gathering to agriculture is routinely associated with declines in oral health because of increased consumption of carbohydrates and growth of bacterial colonies in dental plaque linked to the development of tooth decay,” said Peter Ungar, a distinguished professor of anthropology at the University of Arkansas.
Studies of the Hadza tribe, though, have revealed that gender, residence, and behavior greatly influence oral health. For example, men in the bush experience tooth decay and other issues likely because they use their teeth as tools to make hunting instruments. They also smoke more tobacco, which can lead to cavities. Yet men who live in the village and eat an agricultural diet have much better oral health, including healthier teeth and gums.
Conversely, women who eat wild food diets in the bush have the best oral health, while women on agricultural diets in village have the worst teeth. The researchers concluded that these patterns show how diet and sex interact to lead to oral health outcomes, something that often has been overlooked among populations transitioning from hunting and gathering for food to agriculture.
“The presumptions we have long held about oral health and the transitioning from a foraging to an agricultural diet are not as clear cut as we once thought,” said Crittenden.
Other variables that influence tooth decay in addition to diet and gender include the bacterial environment, oral microbiome, eating frequency, the rate of dental wear, and genetic predisposition. The researchers plan to further study the role that each factor may play in oral health as the Hadza continue their transition away from foraging.
The study, “Oral Health in Transition: The Hadza Foragers of Tanzania,” was published by PLOS One.