Sunrise on Cranberry Mountain

Why Eating Early Can Give You a Metabolic Edge

It’s no guarantee. But with all else being equal, you may find that you have a certain metabolic edge if most of the food you eat comes earlier in the day. New research published by Eric Ravussin and colleagues in Obesity tells us why. Eating early in the day seems to help with hunger. In addition, it may have a favorable effect on burning (aka oxidizing) fat.

A Small Carefully Controlled Study

This latest study is a very small and carefully controlled one. The point was not to ask whether meal timing can help with maintaining a lower weight. That evidence comes from prior, larger studies like this and this. Instead, the objective was to find out why this seems to be true.

Ravussin studied eleven adults in a randomized crossover study. For four days, these subjects either followed a a schedule of eating early in the day (8 am to 2 pm) or all through the day (8 am to 8 pm). On the fourth day, researchers measured their metabolism in a whole-room calorimeter. They also measured hunger and metabolic hormones. And then, after a few weeks, subjects followed the other regimen for four days and took the same measurements.

The results showed that eating early had no effect on how much energy the subjects burned. But it did have a significant effect on hunger and hunger hormones. Those hunger hormone levels were lower when people were on the early feeding schedule. That schedule also caused fewer swings in hunger. That is, fewer bouts of extra hunger.

Senior author Courtney Peterson explained the significance:

We suspect that a majority of people may find meal timing strategies helpful for losing weight or to maintain their weight since these strategies naturally appear to curb appetite, which may help people eat less,

Many Variables in Real Life

Of course, real life is more complicated than a four-day, controlled feeding study. Different people have different chronotypes – circadian rhythms that are different. Also, assuming that a short-term study will predict long-term outcomes can be misleading.

Nonetheless, this study fits with growing evidence that meal timing really does matter. And that evidence aligns with the observations of experienced clinicians. Pat Harper, a dietitian with special expertise in weight management, explains:

In my 25+ years of experience counseling people about weight, skipping breakfast & eating little or nothing at lunch, and then eating most/all calories in the evening is the classic pattern of individuals with obesity.

Every rule has exceptions, but it does appear that eating heavy meals late in the day might make you more vulnerable to gaining and carrying more weight.

Click here for the study by Ravussin et al and here for more on the science of timing of food intake.

Sunrise on Cranberry Mountain, photograph © Ted Kyle / flickr

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July 26, 2019

2 Responses to “Why Eating Early Can Give You a Metabolic Edge”

  1. August 07, 2019 at 2:51 am, Mary-Jo said:

    I always thought eating larger meals later deterred weight loss as well as affecting sleep, digestion, and metabolism. When I lived stateside, it was often the case that people who stayed up late seemed to feel hungrier at night and tend to snack incessantly, even eat enough to constitute a couple meals. But, then, after living abroad, I’ve observed that in countries like Spain, Portugal, and Italy, people eat ‘dinner’ very late (10-11 pm)! And the prevalence of obesity is lower than in the States. ‘Chronotype’, a new term for me, must have something to do with this.

    • August 07, 2019 at 4:15 am, Ted said:

      Very interesting observation Mary-Jo. Perhaps our bodies adapt over time in ways we don’t full appreciate.