Intermittent fasting — skipping some meals, basically — has achieved Hype Factor 10. Everyone is doing it, and almost everyone seems to believe it has substantial general health benefits, a special metabolic sauce that improves us. Not-eating as actual medicine. Specifically, I’m interested in the common claim that it’s anti-inflammatory. If it really is, I want to know about it, and I want my readers to know about it. I finally looked into it, and this is my first take on the topic.
Intermittent fasting was recently given a great boost by the publication of a widely cited New England Journal of Medicine paper (de Cabo et al). It’s basically just a fancy opinion piece, but two authors are pretty excited about fasting. The paper contains an on-the-nose assertion — “intermittent fasting reduces markers of systemic inflammation” — supported by four references. Are they persuasive? Two are underpowered studies that damn with faint praise; two are (sigh) actually a bit negative, true citation backfires. Tch tch: the NEJM authors didn’t read the fine print in what they were citing! So it’s a poor selection of citations to support the assertion that “fasting is anti-inflammatory.”
As far as I know, there is literally only one solid study showing clear evidence of an anti-inflammatory effect in humans (Jordan et al). It is too fresh to have been cited in the NEJM paper.
So the “growing body of evidence” has been exaggerated by everyone, surprise surprise, and fasting has not yet been shown to be “anti-inflammatory” per se. Yet.
The good news
There’s a decent chance that an anti-inflammatory effect of fasting will still be demonstrated. It’s actually quite plausible, based on lots of indirect evidence — animal, cell, more general research, and so on — which truly is accumulating.
It’s also just a reasonable diet. As long as you don’t get too extreme, the worst case scenario is just getting hangry.
Fasting is even useful as a perfectly good weight-loss diet if nothing else. You’ll even save time and money by fasting, which is a great rarity in rehab — even the most harmless treatment experiments usually take some money/time.
I’ve added these comments to my inflammation article, and I’ll be adding more soon.