Unfortunately "easy to imagine" doesn't imply "particularly plausible", although it's an association we all (including me) tend to make. It's easy to imagine th

Unfortunately "easy to imagine" doesn't imply "particularly plausible", although it's an association we all (including me) tend to make. It's easy to imagine that bloodletting is a useful treatment, or that $SOME_GROUP aren't as $SOME_CHARACTERISTIC as $SOME_OTHER_GROUP, but the number of such easy-to-imagine ideas that stand up to public testing by systematic observation, controlled experiment and Bayesian inference is extremely small. So while I don't disagree that it's easy to imagine that our ancestors had intermittent access to food--men of the Piraha people in South America, who live pretty Stone Age lives, are apt to go without food for a day or two just because they can, for example--that doesn't go too far toward increasing the plausibility that such circumstances were common enough to have a significant evolutionary influence, particularly as the evidence for positive effects for women is somewhat weaker than for men, and pregnant and nursing women have more continuous caloric requirements than others (random site with some links on women's response to IF: http://www.marksdailyapple.com/women-and-intermittent-fasting/ http://www.marksdailyapple.com/women-and-intermittent-fastin...) In contrast, we are pretty sure humans evolved as opportunistic hunter-gatherer-scavengers, able to survive on diets and dietary schedules that were extremely variable, from mostly plants in some places to mostly meat in others, and fairly steady food supply to fairly intermittent, all without there being a vast range of average lifespans between them. This suggests that our dietary optimum is broad and shallow, whereas a great deal of dietary research seems aimed at the belief that our dietary optimum is narrow and deep, so if we could just discover the precisely right diet we would live in good health for substantially longer. This may be the case, but my personal bet is that in my lifetime a) no such discovery will be made and b) it will continue to be extremely lucrative selling this implausible idea to the public in various guises, from "superfoods" to weird eating patterns. Of these, intermittent fasting seems at least to be a reasonably effective way of dealing with the caloric overabundance we live in the midst of in the West, and is also well within the (arguably very broad) envelope of our evolutionary adaptations. It is also at the very least benign and quite possibly marginally better than many alternatives.