People aren't changing to vegetarian or vegan diets because of studies. They're changing because they try it and they find themselves feeling better. The main barrier to a vegetarian or vegan lifestyle has always been the bias against ethnic dishes that often were vegetarian or vegan. And all of the European or American style dishes were all meat centered. There has been trend of people becoming more comfortable with a less European an American style diet. A lot of this actually can be chalked up to youtube. People aren't stuck consuming only one corporately cultivated perspective on food prep and recipes. There is now a diversity that has never existed before.