Fasting, or intermittent fasting, has become one of the most popular diet trends. Apparently, not only it is an effective way to lose weight in a relatively short period of time, but also have a number of healthy side effects. Whether chosen a 5:2 or a 16:8 regime, followers of both claim that they have lost weight, eat less, and feel more energetic, among other short term benefits. So far so good. But what do we know about the long term effects of this trending regime?