How does intermittent fasting work and is it effective?

As a weight loss plan, it's easy to see why intermittent fasting is appealing: it involves eating what you want only during certain windows of the day (often eight hours a day).

Courtney Peterson, a nutrition researcher at the University of Alabama at Birmingham, said that instead of counting calories or measuring portion sizes, dieters can simply pay attention to the clock.

“There's a very simple rule: either eat or don't eat,” Peterson says.

This technology has become increasingly popular in recent years. Hot Trending Topics On social media.

But can time-restricted eating, a type of intermittent fasting, really help you lose weight and improve your health?

Here's what you need to know about this practice:

What is Intermittent Fasting?

Intermittent fasting is an eating strategy that alternates between fasting and regular eating schedules, and is defined as not eating for at least 14 hours, says Peterson. Variations of intermittent fasting include eating every other day, eating five days a week and fasting two days, or restricting eating to certain times each day.

Time-restricted eating is the most common form of intermittent fasting, in which you condense your daily eating into a 10-hour window or less: delaying breakfast until 10am or noon, eating dinner by 6pm or 8pm, and abstaining from eating for the rest of the day.

How does that help?

The theory behind time-restricted eating is that it supports your body's circadian rhythm – your body's internal clock – and scientists say that extending your fast, for example, may boost the body's processes that regulate blood sugar and fat metabolism.

Early research in mice beginning in 2012 seemed to suggest that time-restricted eating could have health benefits, and a small study in obese people suggested the practice could help with weight loss and improve other health markers.

Is time restricted eating effective for weight loss?

Research has shown that people on time-restricted eating plans tend to eat fewer calories, which may lead to weight loss.

Results from multiple studies suggest that obese adults who undergo time-restricted eating without focusing on calories naturally reduce their energy intake. 200-550 calories per day, Lose 3% to 5% of your baseline body weight.

However, larger studies with people observed over longer periods have shown that time restrictions alone may not be the problem.

Research published in 2022 New England Journal of Medicine A study of 139 obese people followed them for a year. Participants either consumed a calorie-restricted diet at specific times of the day or ate the same calories throughout the day. Both groups lost an average of 14 to 18 pounds, but the differences between the strategies were not significant.

“Our data to date suggests that time-restricted eating is no better or worse than calorie restriction,” Peterson says, adding that the method also doesn't help you burn calories.

Still, the simplicity of time restriction may make it easier to stick to than a typical diet, Peterson says.

“Very few people like counting calories,” she says.

Is intermittent fasting safe?

Early clinical trials, which involved eating windows of six to 10 hours, found time-restricted eating to be “generally safe,” researchers reported. Journal Obesity.

but Research that grabs attention A study presented at the American Heart Association's Scientific Sessions this year suggested that people who follow an eight-hour time-restricted diet have a much higher risk of death from cardiovascular disease than those who eat over a 12- to 16-hour period.

Dr. Francisco Lopez Jimenez of the Mayo Clinic noted that the study has not been published in a peer-reviewed journal.

But he said there's reason to be careful. Long-standing evidence shows that skipping breakfast can Associated with cardiovascular disease This can be fatal. Consult with your health care provider before restricting your diet, especially if your fasting period lasts until midday.

“We should pause for a moment and think before recommending a particular diet,” Lopez Jimenez says.

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