http://www.bbc.co.uk/news/health-42788280

We all know what makes us fat: eating more in calories than we burn off in energy. But though this is true, it doesn't answer the more interesting question - why do we overeat in the first place?

Why do I sometimes feel compelled to eat that bit of cake or bar of chocolate although I know I am going to regret it a few minutes later?

Is it just greed - or is something else going on?

Although self-control is important, there is mounting evidence that stress plays a significant part in weight gain.