May 15, 2022 11:00:00

What did you find out from an experiment that continued an '8-hour diet' that limits eating time for a year?

There are a wide variety of dieting methods in the world, but one of the things that has been attracting attention in recent years is that you can lose weight by eating 8 hours a day and fasting for the remaining 16 hours. There is an '8 hour diet'.

Clare Collins , a professor of nutrition at Newcastle University, summarizes the results of a study that experimented with the effects of such an eight-hour diet for about a year.

Calorie Restriction with or without Time-Restricted Eating in Weight Loss --PubMed
https://pubmed.ncbi.nlm.nih.gov/35443107/

Restricting calories leads to weight loss, not necessarily the window of time you eat them in
https://theconversation.com/restricting-calories-leads-to-weight-loss-not-necessarily-the-window-of-time-you-eat-them-in-181942

Research teams at the Southern Medical University of China and Tulane University in the United States have shown that there is a difference in weight loss between a normal low-calorie diet and a low-calorie diet with dietary restrictions. I conducted an experiment to find out.

The 139 subjects who participated in the experiment had an average weight of 88 kg and an average age of 32 years. Randomly assigned to a group that limits eating time to 8 hours from 8am to 4pm. Both groups continued their diet for 12 months with the support of their health coaches.

As a result of the experiment, both groups succeeded in losing about 7 to 10% of the weight before the start of the diet. Of these, the group on a low-calorie diet alone lost an average of 6.3 kg, and the group with a time limit in addition to a low-calorie diet lost an average of 8 kg. Focusing on weight, the time limit seems to be more successful in weight loss, but the researchers report that there was no statistical difference between the two groups.

In addition, both groups also had the effect of improving blood glucose level, blood fat level, insulin sensitivity, etc., but no significant difference was confirmed between the groups.

Collins points out that the following four points are important for the results of this study.

◆ 1: The experiment was conducted in China
Many experiments on diet and diet have been conducted in the United States, but this experiment was conducted in Guangzhou, China. Therefore, it can be said that it is the result of an experiment targeting subjects who had a cultural background sensitive to calories compared to experiments conducted in the United States and other countries.

◆ 2: The difference in meal time was about 2.5 hours between the two groups.
Since the average time for subjects in Guangzhou to eat was about 10.5 hours a day, it is calculated that people who diet for 8 hours have an average of 2.5 hours longer fasting time than usual. On the other hand, in the United States, about 90% of adults eat more than 12 hours a day, more than 50% have less than 9 hours of fasting a day, and adults who have more than 12 hours of fasting a day. It's

only about 10% . Also, because many people in China eat the most amount of lunch each day, the fact that lunch was not affected by this time limit may also have an impact on the results.

A 2020 study that analyzed 19 studies on diets that limit meal times showed that limiting meal times reduced weight and body fat in obese people, as well as lowering systolic blood pressure and blood sugar levels. .. So Collins says that in countries where many people eat snacks until midnight and fasting less than China, or where they eat the most at night, an eight-hour diet may still be a useful way to reduce calorie intake. I said I couldn't.

◆ 3: Subject received appropriate diet support
Both groups who participated in the experiment recorded their daily diet and time in the app, and received various support to limit their calorie intake. For the first six months, an alternative diet shake to replace your diet with a low-calorie diet was provided once a day, you received phone calls and app messages twice a week, and a trained health coach every two weeks. I heard that I was interviewed with. Also, for the next six months, he received a phone call and app message once a week, and met with a health coach once a month.

Collins argues that such generous support is very important in a diet. Eight years of intensive lifestyle intervention

studies have shown that long-term support can achieve 3-5% weight loss and reduce the risk of developing type 2 diabetes by 50%. Was also confirmed.

◆ 4: There were individual differences in weight loss even if the restrictions were observed.
In this experiment, 84% of the subjects succeeded in maintaining their daily calorie intake and fasting time, but in the low-calorie diet-only group, weight loss was 4.7 to 7.8 kg, and a time limit was applied to the low-calorie diet. In the added group, the results of weight loss varied from 6.4 to 9.6 kg.