tooth decay

Teeth are able to heal themselves. That's one reason why traditional cultures such as the Inuit can wear their teeth down to the pulp due to chewing leather and sand-covered dried fish, yet still have an exceptionally low rate of tooth decay. It's also how the African Wakamba tribe could traditionally file their front teeth into sharp points without causing decay. Both cultures lost their resistance to tooth decay after adopting nutrient-poor Western foods such as white flour and sugar.