Obesity everywhere is a modern problem. Most populations across the globe ate diets high in some kind of starchy plant food and generally this staple food is what armies were fed with. It's added sugar that's causing all the obesity. I would like to add vegetable oils to that, but I'm not sure if it has contributed to an increase in fat consumption or not. People used to use butter, lard, and tallow a lot. Anyway, one time I went from eating meat to not eating meat, and I went from being skinny to being really skinny. I lost about 15 pounds, and I was already pretty thin to begin with. I was even consuming some sugar but not a lot.