What the science says about intermittent fasting

MANY of my friends have been trying intermittent fasting for weight loss. Does it work, and is it better than other diets?

- TRISHA PASRICHA

Intermittent fasting has been shown to lead to some weight loss in several studies. But it might not work better than other dieting practices.

When scientists compared intermittent fasting to eating fewer calories throughout the day, they found that intermittent fasting wasn’t more effective in helping people shed pounds.

Conventional dieting focuses on what you eat, but intermittent fasting focuses on the time you eat it - within an eight-hour window a day. Because intermittent fasting doesn’t typically require monitoring calories or changing what you eat, it can feel easier to stick with.

Interest in the practice took off, after experiments in animals showed that eating restricted to certain times had a profound impact on metabolic health and the microbiome. But in people, the weight-loss benefits linked to intermittent fasting may be because they took in less food in general — up to 550 fewer calories a day.

Intermittent fasting and overall calorie restriction approaches can result in weight loss for a few months, but they are hard to sustain; studies have shown that some of that weight comes back after a year.