Is it reliable to lose weight by “doing not eat after lunch” or eating one less meal? Recently, Guangdong doctors confirmed through a clinical study that this “time-restricted diet” weight loss method is indeed safe and effective.
However, this is a valid principle: time-restricted eating does reduce calorie intake. In other words, if you only eat one meal less, but eat a lot of the other two meals and the total daily calorie intake does not decrease, weight loss may not be effective.
On April 21, 2022, the team of Zhang Huijie, Department of Endocrinology and Metabolism, Southern Hospital of Southern Medical University, published an online publication titled “CalorieRestrictionwithorwithoutTime-RestrictedEatinginWeightLoss” in the international authoritative journal “The New England Journal of Medicine” (The New England Journal of Medicine, IF=91.245). ” (Clinical study of calorie restriction combined with time-restricted diet and calorie restriction alone in weight loss) research paper.
The team of Zhang Huijie from Nanfang Hospital published clinical research results on time-restricted diet in the international authoritative journal “New England Journal of Medicine”.
Background: The long-term efficacy of “light fasting” remains to be verified.
The corresponding author of this study is Professor Zhang Huijie, Department of Endocrinology and Metabolism, Nanfang Hospital, Southern Medical University. On April 21, at the press conference of the scientific research results of “time-restricted diet and weight loss” in Nanfang Hospital, Zhang Huijie introduced that time-restricted diet is a popular mode of light fasting, which limits the daily eating time window to 8 to 10 hours. , has attracted much attention because of its simplicity and effectiveness in reducing body weight, improving insulin resistance and metabolic disorders.
However, the long-term efficacy of time-restricted diets needs to be further verified, especially the long-term clinical effects of time-restricted diets in weight loss and metabolic improvement compared with simple energy restriction have not been fully evaluated.
Therefore, Huijie Zhang’s team initiated this original clinical trial to investigate the effect of time-restricted diet compared with conventional energy restriction on body weight and cardiometabolic risk factors in obese patients.
Zhang Huijie, Department of Endocrinology and Metabolism, Nanfang Hospital, Southern Medical University, at the press conference on April 21.
How about research? The subjects cut their caloric intake by a quarter
one group stopped eating after 4pm
In this study, the A rigorously screened 139 adult obese patients were randomly assigned to a time-restricted diet group or a conventional energy-restricted group. These obese patients were defined by obesity criteria with a BMI index greater than 28.
Among them, the daily eating time of the time-restricted diet group was 8:00-16:00, and only non-caloric beverages were allowed outside the 8-hour time-restricted diet period, while the regular energy restriction group did not restrict any eating time.
Both groups received the same energy restriction (about 75% of the patient’s daily caloric intake before intervention), 1500-1800 kcal/day for men and 1800 kcal/day for women 1200-1500 kcal/day, maintaining a balanced dietary pattern of carbohydrate energy supply ratio of 40-55%, protein 15-20%, fat 20-30%, and the intervention period was 12 months.
How to ensure that the subjects enter the energy strictly according to the plan? The research team has a nutritionist to provide dietary guidance for obese patients throughout the process, including providing recipes, food matching selection guidance, etc. The research team uses a smartphone app to supervise and guide the diet of obese patients, and conduct face-to-face follow-up to all obese patients 1-2 times a month to measure body weight, assess dietary compliance, and help solve difficulties in implementation. 1-2 online follow-ups such as phone calls or WeChat, completed dietary supervision and guidance, and the time-restricted diet group received supervision and guidance of time-restricted diets at the same time.
During the intervention, obese patients only received behavioral guidance and counseling, and were not required to change their exercise habits or activity levels.
Professor Zhang Huijie introduced the research plan.
After 12 months, the subjects lost an average of more than ten kilograms of weight
Limited time and no time limit can effectively lose weight
The study found that under the intervention of two dietary patterns, time-restricted diet and conventional energy restriction, the average energy intake of obese patients was significantly lower than that before the intervention. Both dietary patterns were well complied with by the patients. Diet compliance rates are above 80%.
“Both groups achieved significant weight loss, weight decreased by 6 to 8 kilograms“, Zhang Huijie introduced, after 12 months of intervention, the patients in the time-restricted diet group were significantly better than those in the time-restricted diet group. The average weight loss at baseline was 8.0 kg, and the average weight loss in the conventional energy restriction group was 6.3 kg; compared with pre-intervention, obese patients in the time-restricted diet group lost 8.6 cm in waist circumference and those in the conventional energy restriction group lost 7.2 cm.
From the data above, is time-restricted eating better than regular energy restriction? According to Zhang Huijie, from a statistical point of view, there is no significant difference in the results of the two groups, “it can be said that the effect is the same, and both are equally effective.”
The research team also found that both dietary patterns were equally effective in improving total body fat content, subcutaneous abdominal fat area, liver fat content, and metabolic risk factors such as blood pressure, blood sugar, and lipid levels.
The obese patients in the time-restricted diet group stopped entering energy after 4 pm. Is this “one less meal” diet safe? According to reports, in the 12 months of dietary intervention, obese patients no serious adverse events, and only some patients reported mild fatigue, dizziness, or gastrointestinal discomfort due to energy restriction. The adverse reactions can be improved after the patients adjust their diets under the guidance of researchers and nutritionists.
Professor Zhang Huijie at the press conference.
Regardless of whether the diet is restricted or not, the key is to reduce calorie intake
Zhang Huijie introduced that the original clinical research results of “time-restricted diet and weight loss” completed by the team over three years show that time-restricted diet intervention A safe, effective and alternative option for weight management.
“At the same time, this result also reminds people that if you use a time-restricted diet to lose weight, you still need to pay attention to the total amount of energy you put in (to reduce it)”, Zhang Huijie emphasized that the research results are internationally recognized. For the first time, it is clarified that the obesity treatment model of time-restricted dieting is mainly due to energy restriction, “Some studies have found that time-restricted eating can affect the biological clock and changes in energy metabolism, but our study found that it is still energy intake. Less is more important”.
Li Wenyuan, president of Nanfang Hospital, at the press conference.
Research results published in top international journals
According to reports, the New England Journal of Medicine is one of the most influential medical journals in the world. Published major medical research results that promote clinical practice, representing the highest level in the field of global clinical medicine, with an impact factor of 91.245. For a long time, few Chinese scholars have published original research papers in the New England Journal of Medicine; in the past 50 years, my country has published no more than 40 original papers in the journal.
The research results of Zhang Huijie’s team are the first research results published in the journal in 2022 in my country, and the first clinical intervention research results published in the journal in the field of metabolism in my country so far.
Li Wenyuan, president of Nanfang Hospital, congratulated the scientific research results of “time-restricted diet and weight loss” for being recognized by top international journals. He introduced that Nanfang Hospital has been adhering to the sustainable development strategy of “reinvigorating the hospital with scientific research and strengthening the hospital with scientific research”, promoting the comprehensive and high-quality development of the hospital. In the past five years, the hospital’s related scientific research achievements have won a total of 18 national and provincial awards. At the just-held Guangdong Science and Technology Innovation Conference, the hospital won a total of 5 first prizes in Guangdong Province’s science and technology. ranked first.
Written by: Southern Metropolis reporter Li Wen correspondent Ling Weiming