Intermittent Fasting Beats Cutting Calories for Weight Loss, Study Finds

A new study has found that fasting three days each week—and eating what you want the other four days—may be more effective for weight loss than counting calories daily.1

Researchers said that when combined with physical activity, the 4:3 intermittent fasting method led to more weight loss than daily calorie restriction, possibly because it was easier to stick with.

In the study, researchers conducted a randomized controlled trial with 165 people aged 18 to 60, though only 125 participants completed the trial.1All participants had a body mass index (BMI) between 17 to 46. A BMI in the 25 to 29.9 range is considered overweight, and a BMI greater than 30 is considered obese.2

Participants were randomly assigned to one of two 12-month programs: daily caloric restriction or 4:3 intermittent fasting. Those in the 4:3 group ate without restriction on four days per week and fasted on three non-consecutive days.1

“Theoretically, with this design, the three-day-a-week intermittent fasting group could potentially overeat over the four days a week they were not fasting and end up in a caloric excess,” said Allison Rhodes, MD, an obesity medicine specialist at The Ohio State University Wexner Medical Center.

However, the study authors found intermittent fasting led to “modestly greater weight loss” than daily caloric restriction. The intermittent fasting group lost about six pounds more than the daily caloric restriction group.1

Counting calories can be hard for people to stick with long-term, which could be why some participants saw greater success with intermittent fasting.