by SHAPE Diet Doc Mike Roussell, phDIntermittent fasting has become increasingly popular over the past several years, especially in the fitness world. But it's not a new trend-fasting has been around for centuries. Fasts have typically been used for religious reasons (Ramadan and Lent are the two most prominent examples), but even Hippocrates used fasting as a means of promoting weight loss:Obese people and those desiring to lose weight should perform hard work before food. Meals should be taken after exertion and while still panting from fatigue. ...