Reducing Calories Offers Same Weight Loss as Intermittent Fasting

New research suggests that individuals can lose weight with either strategy, so they might want to consider personal preference when choosing which to follow.

Intermittent fasting, or time-restricted eating, is a weight loss approach that requires a person to restrict food consumption to a specific time frame throughout the day or week. Though it differs from traditional calorie-counting diets, which involve reducing the overall number of calories consumed, it's unclear if one strategy results in more weight loss than the other.

However, a new study published on June 26 in the Annals of Internal Medicine investigated the two weight loss regimens and found that intermittent fasting yielded virtually the same weight loss as cutting calories in adults with obesity.

To conduct the research, scientists divided 77 adult racially diverse participants with obesity into three groups. One group followed an eight-hour-time-restricted eating pattern which involved eating from noon to 8 pm without counting calories. The second group reduced their calorie intake by 25% over a 10-hour period, while the control group did not change their eating pattern.

Moreover, the participants did not change their activity levels during the 12-month study.

In addition, the intermittent fasting group and calorie restriction group met with a dietician weekly, then biweekly, for six months during the weight loss phase. Then, after six months, the two groups saw a dietician once a month.

At the study's conclusion, the researchers found that the intermittent fasting group consumed 425 fewer calories per day and lost about 10 pounds more than the control group at 12 months.

However, weight loss was similar among participants in the calorie restriction group. Compared to the control group, calorie-restricting participants reduced their caloric intake by an average of 405 more calories per day and lost nearly 12 more pounds of body weight.

While both groups lost weight, the scientists found no significant differences in calorie intake reduction or weight loss between the intermittent fasting and calorie restriction groups. Still, more research is needed to confirm these findings.

In an editorial accompanying the study, Victoria Catenacci, M.D., and Adam Gilden, M.D., from the University of Colorado Medicine, Aurora, suggests that meeting with a dietician likely helped participants in the calorie-restricted eating group choose healthier foods. Moreover, they say this study shows that considering an individual's preferences rather than randomly selecting a diet plan may be a more effective strategy for weight loss.