Fasting Every Other Day Does Not Lead to Greater Weight Loss

By Amy Orciari Herman

Edited by David G. Fairchild, MD, MPH, and Jaye Elizabeth Hefner, MD

Fasting every other day is not better than daily calorie restriction in terms of weight loss or subsequent weight maintenance, a JAMA Internal Medicine study finds.

One hundred overweight or obese adults were randomized to alternate-day fasting, daily calorie restriction, or no intervention for 6 months. With alternate-day fasting, participants consumed 25% of their baseline calorie intake every other day (fasting days), and 125% of their baseline intake on the intervening days (feasting days). With daily calorie restriction, participants consumed 75% of their baseline intake every day.

Participants were less adherent to alternate-day fasting than daily calorie restriction (dropout rate: 38% vs. 29%). At 6 months, both intervention groups had lost weight, but there was no difference between the two interventions. In addition, during months 6 through 12 — the weight-maintenance phase — weight regain did not differ significantly across the intervention and control groups.

Most risk indicators for cardiovascular disease, including blood pressure, triglycerides, and glucose, did not differ between the intervention groups.