The Science is Not Settled

From April, 2013

We first tried the fasting diet six years ago and dropped 10 pounds in a little over a month. The program recommends two fasting days per week, but frankly we don't have the willpower. We fast one day a week, and the weight has stabilized.

One focus of research has been "mini"-fasting, that is, limiting one's eating during an 8-9 hour stretch each day:

[Biologist Satchidananda Panda at California’s Salk Institute] fed a group of mice a high-fat diet around the clock for 18 weeks; they developed fatty livers, pancreatic disease and diabetes. Another group was fed the exact same number of calories a day, but all during an eight-hour span. Surprisingly, the second group stayed slimmer and healthier for much longer.

There is a logic to it. When we eat, our body releases insulin. That disrupts the process of autophagy (from the Greek, meaning “self-devouring”), by which cells deconstruct old, damaged components in order to release energy and build new molecules. Autophagy helps to counteract the aging of cells and builds immunity. Fasts stimulate autophagy and allow the full molecular process to take place, as a team led by Frank Madeo at the University of Graz in Austria found in 2017.

Eat during a fraction of the day (WSJ)

If fasting enthusiasts are correct, the food science we learned a few years ago was wrong:

1) "Break-fast" is not the most important meal of the day; skipping it entirely may be beneficial.

2) Autophagy (devouring one's own cells) can sometimes be a good thing. Cutting out late-night snacks has long been recommended, but now it is more than about not taking in calories. The autophagy should not be interrupted.

3) A heavy lunch is the way to go ("we should eat lunch like kings. A rich lunch beats a robust dinner.") We had thought that a work-out--even just going walking--was preferable not only for the exercise and the food eschewing, but also for forestalling the afternoon sleepiness at the office.

The science of the stomach is still churning.