I’ve long thought the human body was not meant to run on empty, that fasting was done primarily for religious reasons or political protest. Otherwise we needed a reliably renewed source of fuel to function optimally, mentally and emotionally as well as physically.
Personal experience reinforced that concept; I’m not pleasant to be around when I’m hungry. There’s even an official name for that state of mind, confirmed by research: Hangry!
But prompted by recent enthusiasm for fasting among people concerned about their health, weight or longevity, I looked into the evidence for possible benefits — and risks — of what researchers call intermittent fasting. Popular regimens range from ingesting few if any calories all day every other day or several times a week to fasting for 16 hours or more every day.
Excerpted from The New York Times