The average diet has evolved significantly, even over the last few decades, let alone over the past few thousand years. In the past, humans were hunter-gatherers, eating tough grains and chewy meat, and it wasn’t so easy to cook food to make it softer. Nowadays, we have easy access to virtually any type of food, even having it delivered to our door. The change in diet seems to be affecting people’s teeth and jaws, which were originally designed to eat harder foods that were more difficult to chew. In comparison, the modern diet tends to focus on much softer foods that often require minimal or no chewing to swallow and digest.
When our ancestors ate these harder-to-chew foods, it stimulated jaw growth and enabled the jaws to grow properly to accommodate the third molars or wisdom teeth when they erupted. Now, it’s increasingly common for people to have insufficient room for their wisdom teeth, resulting in problems with tooth misalignment. Removing wisdom teeth because of a lack of room in the jaw is quite usual and is almost a rite of passage. Before the agricultural revolution, it was virtually unheard of for people to have impacted wisdom teeth.
A lack of chewing also affects jawbone growth in other ways and can result in narrower dental arches. A closer examination of the skulls of our ancestors showed that they generally had broad, well-developed dental arches providing plenty of room for teeth to erupt without malocclusion problems. Evidence to support this view comes from some developing countries where their diet is closer to those of their ancestors. As a result, these countries have fewer problems with misaligned teeth compared to more developed countries where the diet involves foods that are considerably easier to chew.
Some experiments have backed up these theories and were conducted with baboons that were fed very soft diets. Consequently, their jaws didn’t grow large enough, and they developed more problems with malocclusion than other baboons eating more conventional diets for these primates.
Another modern-day problem is refined sugar. You would think that if you examine the teeth of our ancestors that they would be full of decay due to the lack of knowledge and access to good dental care. However, this isn’t the case, and it’s rare to find teeth that had cavities in the bones of our ancestors.
You might wonder what we can do about this problem, and one solution is to introduce harder foods into our diet, especially in children’s diets. However, to make any difference, it would probably need to be a large quantity of more fibrous food, not just crunching down on the occasional apple, so this approach is not entirely practical. If you have children, the best approach is to make sure they visit us regularly for checkups, where we can monitor the growth and development of their teeth and jaws and detect any problems early on. Sometimes early treatment can help widen narrow arches, creating a better facial profile that can accommodate a complete set of adult teeth.