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New study weighs time-restricted eating versus total calorie intake for weight loss

Posted at 3:48 PM, Apr 22, 2024

(WXYZ) — In today’s Health Alert, time-restricted eating has become a popular way to lose weight.  But is it the meal timing or total calorie intake that holds the key to weight loss?

A recent study aimed to answer that.

I often get asked for dietary advice by my patients, especially about time-restricted eating. That’s when you only eat within a certain period of time in a 24-hour period. Now I know lots of people swear by its effectiveness, believing that the restricted window gives the body more time to burn fat. But here’s what the latest study from John Hopkins University discovered – that it doesn’t make a significant difference.

Here’s how they arrived at that conclusion. 41 prediabetic and obese adults were split into two groups. Both groups received meals with identical calorie counts. However, one group was instructed to eat all their food within a 10-hour window, with most of their calories eaten before 1 p.m. The other group had a 16-hour eating window but needed to eat half of their calories after 5 p.m.

After 12 weeks, researchers found that the participants following the time-restricted eating regimen lost just slightly over 5 pounds on average. Whereas those who could eat regularly lost a bit more, around 5.7 pounds on average. Overall, the numbers were very close and suggest that time-restricted eating may not be any more effective than simply eating fewer calories.

Some folks feel that time-restricted eating can improve their overall health by potentially improving blood pressure, triglyceride levels, and cholesterol. And it likely does if people consistently fill their plates with healthy, nutritious foods. However, studies investigating health benefits have found mixed results. And some can even be alarming. For example, a recent study on intermittent fasting suggested a 91% higher risk of death from heart disease for people who only eat during an eight-hour window.

But back to the Johns Hopkins University study, researchers did not find any differences in health indicators like blood sugar levels between the two groups.

So, the choice between cutting calories or restricting the hours you eat boils down to personal preference. Some people who attempt the restrictive diet may find themselves binging during the time they can eat, while others who don’t want to count calories may prefer restricting their eating times.

The bottom line is that it appears to be more about the amount of calories a person eats while awake, more so than restricting when food is eaten. And, of course, it’s always a good idea to run any new diet change by your family doctor first.