Losing weight is hard, and obesity is one of the unhealthiest things that can happen to your body. It increases your risk of diabetes, heart attacks, cancer, and can lead to a series of other health complications. But today, the new weight loss drugs are changing people’s lives in a way no diet ever has before. They seem to melt fat away, reduce addiction and even prevent or reverse the negative effects of obesity. How do these drugs work? What do they do to our metabolism, and could they change public health forever?