Intermittent Fasting Strikes Out Again

Breakfast TimeSomehow, we’re beginning to detect a pattern. Yet another hot concept in weight loss – intermittent fasting, a.k.a. time restricted eating – once again is showing no better results than simple calorie restriction. Could it be a safe bet that the diet du jour will always turn out to be a big yawn? Though hope springs eternal, it’s beginning to look that way. In a well-controlled 12-month study, intermittent fasting strikes out again.

This time, with the study published in the New England Journal of Medicine, the disappointment stings a little more for true believers.

A Well-Controlled 12-Month Study

This was a solid study. A total of 139 patients received a random assignment to either calorie restriction alone or calorie restriction plus time restriction. Both groups received a diet that reduced their daily calories by 25 percent. But the time-restricted group limited their eating to an eight hour period each day – from 8:00 a.m. to 4:00 p.m. Average BMI was between 31 and 32 in both groups.

Adherence was good. Almost 85 percent of patients who started the study finished it. Actual adherence to the two different regimens came in at about 80 percent. These patients were carefully coached and monitored, so the study doesn’t give us a real-world answer to how easy it might be to follow such an intermittent fasting diet.

But the answer remains clear. In these patients, time restricted eating did not yield any more weight loss than calorie restriction alone.

A Familiar Story

This is not the first study to suggest that there’s nothing magical about intermittent fasting. Last year in Science Translational Medicine, a well-controlled study of alternate day fasting showed no advantage for that that approach. Also last year, JAMA Open Networks published an umbrella review of intermittent fasting. These researchers found some advantages for some patients, but no overwhelming advantage for all comers. In 2018, an RCT of the 5:2 intermittent fasting regimen found that it had no advantage over continuous calorie restriction.

This is a repeating pattern. Diets are complex and there are many possibilities for changing them up. Low fat, low carb, keto, and so on – the list is quite long for diets that have soared in popularity and then crashed.

Realistic Expectations for Healthy Enjoyment of Food

Seeing this latest result, where intermittent fasting strikes out in a rigorous study, might bring expectations back down to earth. As with every other diet strategy, results undoubtedly will vary from person to person. No doubt, future research will continue to tell us more about the effects of intermittent fasting and maybe even help target it to the patients who will benefit most.

At the end of the day, we will likely wind up where we started. The best strategy is to find a healthy pattern of eating that you can enjoy and keep following over time. Don’t expect miracles, but do expect good things from life – including the nourishment of food.

Click here for the new study and here for a “yes, but” editorial to go with it. For further perspective, click here.

Breakfast Time, painting by Konstantin Korovin / WikiArt

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April 21, 2022

2 Responses to “Intermittent Fasting Strikes Out Again”

  1. April 21, 2022 at 11:58 am, Angela Golden said:

    Thanks for bringing this forward. I hadn’t seen it yet. I think this just once more shows why there isn’t “ONE WAY” to treat the many forms of obesity and why creating the individualized plan is so critical. I have numerous patients that love using time restricted feeding. They feel it makes it much easier to control their eating, while others found it impossible to follow. In my opinion this is what makes treating obesity so incredible and patient centered. We have to find the eating plan that works for the individual in their obesity treatment and weight loss journey.

  2. April 22, 2022 at 2:26 am, Ed said:

    Great Article: I have been intermittent fasting for 25 years and what it does for my health has gave me amazing results. I am 66 years old I feel and run around like a 45 year old man. My secret is that I eat 90% Great nutritious plant food take 5000iu of organic vitamin D3 and a super organic fish oil. My tip to everyone is do not sit very long. The body needs to move. So exercises, square breathing and also active bacterial cultures along with lots of fiber. Life and death begins in the digestive tract.