"There is a simpler question - could one tell anxiety from hunger? (I can't) or the feeling of being hungry "reuses anxiety" in context? This explains why stressed people are overeating - they misinterpret their anxiety as feeling hungry and develop a habit of "eating it over".
Actually it doesn't. Why are they feeling anxious? How do they misinterpret anxiety for the feeling of hunger? Why is the feeling of anxiety and hunger the same (as you assert, I strongly disagree). It is not even close to as simple as you suggest. Maybe bacteria has a role and maybe not. What is known is that the microbiome does have a larger role to play then we currently understand/realize. To what extent and exactly how is still an open question.
Because which set of bacteria one has in ones gut depends of location, season, humidity, air quality, traditional foods, water sources, other bacteria an another hundred factors.
This explains why stressed people are overeating - they misinterpret their anxiety as feeling hungry and develop a habit of "eating it over".
Bacteria stuff is just BS.