I have been intermittent fasting (one to two 24 hour periods a week) for several months and have lost fat and increased muscle mass with really no negative side

I have been intermittent fasting (one to two 24 hour periods a week) for several months and have lost fat and increased muscle mass with really no negative side effects. The key is to lift weights to prevent muscle loss and to eat reasonably balanced diets (and enough calories) on non fasting-days. “Eat Stop Eat” has a good overview of the science behind it all (I have no association with the author)