Research shows that it doesn’t matter how long you eat to lose weight
The latest food trends promise that watches are as important as scales for weight loss. One such diet is called intermittent fasting, which involves an alternating schedule of fasting and eating. A popular intermittent fasting program is time-restricted eating. By restricting eating to a limited number of hours per day, some proponents of this diet argue that people can use the body’s natural rhythms to lose weight.
But according to new research, a recently published study Journal of the American Heart Association Jan 18 When you eat, it doesn’t seem to help you lose weight by itself.
In the study, 547 participants used a phone app to track their daily meals over a six-month period, and researchers used the app to determine the average amount of time each person ate each day; how many times they ate; whether participants described each meal as small, medium, or large; and how much weight they gained or lost. Ultimately, they found that the time between the participants’ first and last meal and whether they ate when they were awake or asleep had no effect on weight. The size of the participants’ meals was important: those who ate larger or medium meals tended to gain weight, while those who ate smaller meals were more likely to lose weight.
Study co-author Dr. Wendy Bennett, MD and associate professor of primary care at the Johns Hopkins School of Medicine, noted that this isn’t the final word on meal times, in part because it was an observational study, so the researchers didn’t control it. for situations that arise, such as calories consumed. Several factors could confound the results, including the small sample size, said Christa Varady, who studies intermittent fasting at the University of Illinois at Chicago and was not involved in the study. , its reliance on participants describing the amount of food as large or small—not actual calories—and the use of different scales to measure participants in medical offices.
Still, Varady agrees that there doesn’t seem to be any magic in eating at certain times. But that doesn’t mean it’s a completely useless concept. Restricting what you eat at certain times can help people lose weight, Varady says, if it makes you eat less. Some say it can be easier than other diets that require counting calories. For example, he says, previous research suggests that eating within a six- to eight-hour window, such as 10 a.m. to 4 p.m. (six hours) or 9 a.m. to 5 p.m. (eight hours), can be beneficial. hours).
Dr. Nisa Maruthur, an associate professor at the Johns Hopkins School of Medicine, agrees. “If your calories are the same regardless of when you eat them, weight won’t be affected,” says Maruthur. However, setting time limits can help. “If you decide to only eat between 10am and 4pm, you may actually be eating fewer calories for your workout. [in] so much [meals] at the same time.” Maruthur, who was not involved in this study but is involved in a larger meal timing research initiative at Johns Hopkins, says that even if eating at a particular time is not healthy, if it helps a particular person to eat, he advises eating at the right time. healthy “The best diet for anyone is the diet they follow,” she says. “If it’s easier for some people to eat healthy foods because they plan more,” she says, time-restricted eating can be beneficial.
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