There is a fad of late called intermittent fasting, or IF for short. Adherents promote various versions. For example, eat only every other day, limit eating time to just a 6 or 8 hour window a day, go on a water fast for multiple days, etc. Some even go on prolonged water fasts for multiple days at a time – or even weeks!
These people claim various benefits, including faster weight loss, changing the body’s metabolism, better long term weight loss, curing disease, and whatnot.
Dr. Michael Greger, the author of “How to Not Die” and the upcoming “How to Not Diet” has researched fasting intensively for his new book, and has been releasing videos at his site lately ahead of the release.
His very reasonable conclusion, I’m happy and relieved to say, is that not only can IF be dangerous if not done under strict medical supervision, but there are no benefits at all for weight loss, as compared to just ordinary reasonable calorie restriction.
Here are some of his recent videos. Note: I can’t stand listening to his voice, so I watch these on mute. They are all closed captioned.
This video shows that eating every other day can actually increase your cholesterol: https://nutritionfacts.org/video/is-alternate-day-intermittent-fasting-safe
IF can actually slow body fat loss (like keto): https://nutritionfacts.org/video/is-fasting-beneficial-for-weight-loss/
It doesn’t make any difference at all whether you do intermittent fasting or continuous calorie restriction. In other words, a regular calorie restricted diet has the same effect. https://nutritionfacts.org/video/Alternate-Day-Intermittent-Fasting-Put-to-the-Test
There is no advantage to intermittent fasting for weight loss. It might be dangerous. It’s completely unnecessary. Plus, to me, the whole idea seems contrived and unpleasant. I like eating. I eat healthily now. I’m down 101 lb and just have 16.5 lb to go to achieve a normal BMI. I did this without any fasting at all. I don’t ever feel deprived. I eat lots of healthy foods (whole food plant based) on a normal, daily schedule.
My personal feeling is that IF is just one of those fads. If you’re interested in it check the actual research out before trying it.