The unfortunate normalisation of sugary and industrial foods spreading rapidly across the world is causing this. Crap food is relativelly cheaper, widely avaliable and easier to consume, doesn't require much preparation so people tend to make these food choices, which causes, among other things, problems like diabetes in first world countries and now in developing countries especially in Asia and South America where this modern lifestyle is being implemented at a very fast rate. Add to this the increasingly sedentary lifestyle that people have, especially in cities, and you will see obesity and diabetes.
Awhiskeydrunker