Intermittent fasting may not be as helpful for weight loss as once thought, study finds

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Are snacks before bed your vice? Or do you prefer to wait a few hours after waking up to eat?

Meal timing may not have as big an impact on weight as once thought, according to a new study.

The study tracked the portion sizes and meal times of 547 people, in addition to their health and weight data, over a period of six years. The data showed no association between an interval of the day during which people ate their meals and their weight, according to the study published Wednesday in the Journal of the American Heart Association.

Restricting meal times, as seen in dietary trends such as intermittent fasting, has been a popular method of trying to lose weight in recent years.

But the researchers found no association between restricting meal times and weight loss, said the study’s lead researcher, Dr. Wendy Bennett, associate professor of medicine in the division of general internal medicine at the Johns Hopkins School of Medicine. This included how long people ate after waking up, how long their eating window was throughout the day and how far they ate before going to bed, she noted.

Instead, smaller meals were associated with weight loss, she said.

“Based on other published studies, including ours, we’re starting to think that scheduling meals throughout the day probably doesn’t immediately lead to weight loss,” Bennett said, adding the update. cautions that for some people, the meal schedule can be a useful tool for tracking nutrition.

The results of this study should be taken with a grain of salt, experts warned.

There were few racial and ethnic minorities among the attendees, noted Dr. Fatima Cody, associate professor of medicine at Harvard Medical School. There are also many social determinants of health, such as people’s stress and environment, that could be added to the data, Cody added.

These factors could be important for better understanding the effects of mealtime, added Alice Lichtenstein, professor of nutrition science and policy at Tufts University.

“I suspect that if they looked at the data more closely, there would be subgroups (where meal timing) might have had a significant effect,” Lichtenstein said.

This study was observational, Bennett noted, meaning they looked at existing designs for the study instead of making changes to a randomized group. Further work on this topic is underway, she added.

The big takeaways are that there’s no one strategy that works for everyone when it comes to nutrition, and food quality matters, Lichtenstein said.

“If you make an effort to have a healthy diet, you make an effort to be physically active, you’re less likely to have diabetes, chronic kidney disease, obstructive pulmonary disease, and hypertension,” Lichtenstein said.

It’s the boring stuff that no one wants to hear, she added, but there’s no getting away from eating fruits and vegetables and being active when it comes to to manage their weight.

For some people, trying intermittent fasting or limiting the intervals between meals can be a helpful way to take note of personal tendencies, but many people can’t sustain it long enough to see long-term change — or avoid losing. of weight, Lichtenstein added.

Cody, who is an obesity medicine physician at Massachusetts General Hospital Weight Center in Boston, doesn’t like to focus too much on calorie restriction or intermittent fasting, she said. Instead, she wants her customers to review the nutritional value of the foods they eat.

For the body, 100 calories of gummy bears is not the same as 100 calories of oatmeal with fruit and nuts, she added.

But different approaches work better in different lifestyles, and everyone should work with their own doctor and their own body without stress or shame, Cody said.

If a nutritional strategy works for someone else, she says, “it just means that someone’s body reacted and the other didn’t. That doesn’t mean you have flaws. It just means it’s just not what your body needed.

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