Study: Time-restricted eating for 10 hours has the same weight loss effect as 16 hours

When many people try the "time-restricted eating method", they often wonder whether simply shortening the meal time can really bring about additional weight loss if they consume exactly the same calories. A human trial at Johns Hopkins University School of Medicine in the United States found that under the premise of maintaining an isocaloric diet, eating all meals within 10 hours a day resulted in weight loss after 12 weeks that was similar to eating spread out over 16 hours.

Science news website "SciTechDaily" reported that this study published in the international journal "Obesity" mainly wanted to confirm whether simply shortening the daily eating time would bring about different weight loss or physiological effects when the calories are the same. The research team designed a 12-week randomized feeding trial. The meals were prepared by research nutritionists and the calories were set according to the needs of each subject to maintain the starting weight.

A total of 39 obese adults with prediabetes or type 2 diabetes who were under dietary control were included in this analysis. They were randomly divided into two groups: one group had to eat all meals within a fixed 10 hours a day and then fasted for about 14 hours; the other group had meals of the same calories spread out over 16 hours.

After 12 weeks of follow-up, the median weight loss in the 10-hour group was 2.7%, and that in the 16-hour group was 2.5%. There was no significant difference in weight loss between the two groups. The questionnaire also showed that both groups had improvements in indicators such as dietary restraint, eating due to stress, and hunger levels, but there were no significant differences between the groups.

Hormone and inflammation indicators were similar between the two groups

The research team further tested fasting blood samples and analyzed appetite hormones such as ghrelin and leptin, as well as inflammation-related indicators such as C-reactive protein (CRP) and cortisol. The results also found no significant difference between eating after 10 hours and eating after 16 hours.

Daisy Duan, first author of the study and assistant professor of medicine at the Johns Hopkins University School of Medicine, said that 10-hour time-restricted eating can be accompanied by mild weight loss and improvement in eating behavior without deliberate calorie restriction, but the study found no additional systemic health benefits.

This research was supported by the National Institutes of Health (NIH) and the American Heart Association (AHA). Since there were only 39 samples analyzed this time, and 92% were women, the research team will further explore in the future whether time-restricted eating can help people who have successfully lost weight through GLP-1 receptor agonists and other methods to maintain their weight loss results.