I have to suspect that the rise of obesity has something to do with something I'd describe as "3 kinds of appetite": - one for taste (dopamine) - one for ener

I have to suspect that the rise of obesity has something to do with something I'd describe as "3 kinds of appetite": - one for taste (dopamine) - one for energy (calories from carbs / fats) - one for the resources that actually are required to build cells etc. And basically you can satisfy the first two as much as you want but if you're eating low nutrient density food, your body will just make you eat enough of it until it's gotten what it takes to live. Of course this is a massive massive oversimplification.. but it does produce as an implication the hardly-disputed rule of thumb "eat nutrient dense food that is not excessively fatty/sugary/addictive" Anecdata, but, I've also witnessed the reverse thing happen on college campuses where the food is overall pretty healthy, with rare treats - that people can lose weight. Goes without saying that it also depends on stress. And people tend to be really really stressed (by default and not exception) these days for whatever reason.