I doubt it. There is no real evidence for genetics playing a major role here. You are probably underestimating your friends' energy intake. Exercise is great fo

I doubt it. There is no real evidence for genetics playing a major role here. You are probably underestimating your friends' energy intake. Exercise is great for many reasons but you can't outrun a bad diet. They're probably eating a lot more than you think, especially when you're not around.