Modern Diseases: Deviations from Nature

Chewing and Diet

To answer this, we must think about how pre-civilization humans used their jaws. As hunter gatherers, these people spent the majority of their day chewing tough meat and plant fiber. Aha! Here we find a major difference between what our jaws developed to do and how we now use them. When humans evolved hundreds of thousands of years ago, we were stressing out our jaws severely, causing microscopic damage to the bone. By the time wisdom teeth came in, the damage and repair had created a much larger jaw capable of holding wisdom teeth in place.

Compare this to present day. We probably spend under 30 minutes a day chewing food, almost 20 times less than our ancestors. While this provides easy nutrition, our jaws never get damaged and thus have no reason to grow bigger and stronger (homeostasis). This means our jaws remain small for life. When our genes instruct the body to grow new teeth, the body is not properly developed, resulting in pain and suffering.

A Laundry List of Mismatch Diseases

There are several more interesting examples of too little stimuli that I will briefly cover here:

1. Sweating: While we already discussed that humans evolved the unique ability to sweat profusely, it turns out that the number of active sweat glands depends on how much heat we were exposed to in infancy. When we keep our kids in air conditioned environments for the first two years of life, we are signalling the body to keep sweat glands inactivated to save energy. This mass deactivation is irreversible and remains with you for life.
2. Allergies: There is such a thing as too clean. Our bodies evolved while being constantly exposed to pathogens from dirt and animals. Thus, our immune system has developed to recognize agents as dangerous very fast. When children are not exposed to many pathogens, our immune system becomes “trigger happy” since it has not been exposed to what it expects after millions of years of evolution. It tags harmless agents as dangerous and creates allergies. Allergies are actually a very new problem for the human species.
3. Vitamin Deficiency: In the ancient diet, various plants and meats were eaten every day, fulfilling vitamin requirements. Ever since the rise of food production (Part 2), reduced diversity has created vitamin deficiencies in human populations worldwide. While modern medicine continues to treat associated diseases (scurvy, rickets, etc.), its effects are still evident as we age.