As Cosmo Kramer said: “I don’t argue with the body, Jerry. It’s an argument you can’t win.”
Five years ago — intrigued by studies showing fasting caused beneficial changes in mice, including decreased inflammation and obesity prevention — I began a regimen of time-restricted eating to lose weight. I ate only in an eight-hour window, starting at 1:30 PM every day — whatever I wanted, but with a hard stop at 9:30 PM. And I reached my goal: I lost as much as 20 pounds from my starting weight over the course of a year and stabilized at about 16 pounds lost. Having struggled with weight issues since my teens, I was thrilled.
Today, I’ve gained back all the lost weight plus five pounds.
For one thing, from 11:30 AM on every day, I was staring at the clock, drooling, counting the seconds. I learned not to schedule meetings during the last two hours of the fast, because I couldn’t account for my statements or actions.
Another problem: My eight-hour eating window was more like a continuous feeding frenzy at a Las Vegas casino buffet. The pleasure of food vanished. At times I felt like I was trying to put out a fire (my hunger) with gasoline.
Third problem: Coffee without dairy is ridiculous.
So I altered my regimen — modifying my fast to 12 hours a day, which felt more in line with my natural rhythms. My sanity quickly returned, as did my delight in food. But so did the pounds — slowly at first, and then uncontrollably.
Many people claim all sorts of health gains through intermittent fasting — not just weight loss, but better increased energy, sharper and more durable focus and the disappearance of various long-standing ailments, to name but a few benefits. (The hypotheses for why intermittent fasting seems to achieve these benefits are almost as numerous as the claims themselves.)
But these claims have been almost exclusively anecdotal. The science has remained largely confined to studies on animals or small, short-term studies on humans where the benefits could have been attributed to other variables (such as resistance training or eating earlier in the day).
Now, a new study just published in JAMA Internal Medicine finds that time-restricted eating over a three-month period didn’t help people lose more weight over a control group. Even worse, the group that ate on a time-restricted schedule lost muscle mass, which the control group did not.
The senior researcher on the study, Ethan Weiss, had been doing time-restricted eating for more than five years before the results, which persuaded him to go back to eating breakfast. He told the New York Times that “my bias was that this works and I’m doing it myself, and so I was shocked by the results.”
So are a lot of other people, to judge by the reactions to Weiss’s Twitter thread when the study was published as well as the comments on the Times article covering the study. The study — which, like all studies, is just one piece of the puzzle — has prompted denunciations as well as smug I-told-you-sos. A typical comment:
Based on readers comments, including my own, IF seems to be a very effective and healthy lifestyle choice for many.
This appears to be a poorly constructed study, without any potential for the verification of compliance by the participants.
I have been doing 16/8 intermittent fasting for a few years now. I believe it is powerful tool. IF is not a diet, nor is it exclusively a weight loss strategy. It is a lifestyle and mechanism to support healthy living. The benefits of IF come from improvements in insulin resistance, cellular health (mitochondria), gut health (microbiome), autophagy, and adrenal and hormone regulation balance. I did not do IF to lose weight. The benefits for me include increased and steadier energy throughout the day, improved sleep, improved cognitive function, and less cravings.
None of those benefits mentioned above have been demonstrated by research in humans. Either the commenter believes they do, or doesn’t care.
Science is great — at least until our bodies (individually, collectively) seem to contradict it.
Let’s say the science continues to accumulate that time-restricted eating (at least, on its own) doesn’t produce many of the benefits in humans its fans claim. How effective has research communication been — and will it be — in persuading adherents of intermittent fasting that they’re “wrong”? Especially when they feel the practice has transformed their bodies and lives?
For that matter, if the science eventually demonstrates those benefits in humans, will that persuade me to try time-restricted eating again?
How can conventional research communication convince Donald Trump and his millions of supporters that he has not, in fact, had a near-miraculous recovery from COVID-19? And how different is that from the belief (in the absence of data) that intermittent fasting is a “powerful tool”?
Here’s where we are today: From vaccines to 5G to COVID to intermittent fasting to climate change, the closer research gets to the body and identity these days, the more our individual experience becomes the data point that occludes all others … except the ones that match our own.
Science will continue to lose these arguments unless it finds another way to make them.