The various neurotransmitters of the body responsible for a sense of well-being and for anxiety are placed all through the digestive tract as much as they are the brain. This is fact.
The release of stress hormones is known to be cosmetically unfriendly. Many know that if you are stressed you start to hold water, become bloated, maybe gassy, crampy – either constipated or just the opposite. And most of you know that stress and worry can induce these physiological responses. It is no coincidence that these same general symptoms are common among all the various “food” related digestive disorders and allergies and intolerances that the modern civilized world has manufactured for you – so now you can have something else to “worry” about, food itself and of course a marketed solution to solve it for you. (Paleo, Gluten free, low carb, etc…)
It’s ironic that most of these disorders are unheard of in Europe in the areas where people still live traditional lives where their mindsets toward food is of enjoyment, not fear and stress.
The tension you have been led to internalize about eating right foods vs. wrong foods is as much a contributor to any food allergy illness aversion you ‘think’ you have over anything you are actually eating.
When I say this, people love to get all offended and defend their victim status. They love being victims of food and digestive ailments. Even “Modern Nutrition in Health and Disease” estimates that over 90% of people with these various food issues digestive disorders actually do NOT have them. But they love to think they do. And this is pretty much a North American phenomenon.