"Clean eating" took simple basic nutritional advice (eat more vegetables and less meat) and turned it into a cult of rigid narrow diets that often harm people's health.

The author suggests this is the result of a generalized fear of some unidentifiable toxin in our food.

There are toxins in our food, and water. Some of them are natural, while some come from industrial pollution. In a few places, pollution taken into the stomach causes real harm to people's health. For humanity overall, we don't know.