While many claim success using this method, a new study suggests it might not be the best way to go.
The study, published in the journal JAMA Internal Medicine, looked at whether alternate-day fasting was more effective for weight loss and weight maintenance compared with daily calorie restriction. The randomized clinical trial, conducted by researchers from the University of Illinois at Chicago, followed 100 metabolically healthy obese adults for a year. They were placed into three groups: an alternate-day fasting group, a calorie-restriction group, and a no-intervention control group.
Those in the alternate-fasting group consumed 25% of their typical calorie intake (about 500 calories) on fasting days, and 125% of their typical intake on ‘feasting’ days. The calorie-restriction group (on a traditional diet) consumed 75% of their typical caloric intake every day.
After analysing the data the authors discovered that, contrary to expectations, alternate-day fasting diet was not superior to the daily calorie-restriction diet with regard to adherence, weight loss, weight maintenance, or improvement in risk indicators for cardiovascular disease including blood pressure, cholesterol and glucose levels.
Both groups did lose weight, with a 6% loss for the alternate-day fasting group and a 5.3% loss for the daily calorie-restriction group. As far as regaining the weight, the researchers determined that, after 6 months of follow up, there was not a significant difference between the two groups.