Eight-Hour Eating Window Sustains Long-Term Weight Loss, One-Year Follow-Up Study Shows
核心洞察
A 12-week intermittent fasting intervention using a 16:8 approach helped overweight and obese adults maintain significantly greater weight loss 12 months after the program ended.
Both early (9 a.m.–5 p.m.) and late (1 p.m.–9 p.m.) eating windows proved effective, with the early fasting group also preserving greater reductions in fat mass.
One in three participants continued practicing intermittent fasting on their own during the follow-up year, suggesting the habit is relatively easy to integrate into daily life.
A team of researchers from the University of Granada (UGR), the Granada Institute for Biomedical Research (ibs.GRANADA (搜索)), the Public University of Navarra (搜索), and the Biomedical Research Networking Center (CIBER) has demonstrated that limiting food intake to an eight-hour daily window helps overweight and obese adults maintain weight loss a full year after the intervention ends. The study, published in the journal Clinical Nutrition, provides the first evidence that the benefits of intermittent fasting persist well beyond the initial treatment period.
The research followed 99 adults—half of whom were women—who were overweight or obese. During the first 12 weeks, all participants received education on following a Mediterranean diet and were divided into four groups: a control group that maintained its usual eating window of 12 hours or longer, an early fasting group with an eight-hour window beginning before 10:00 a.m., a late fasting group with an eight-hour window beginning after 1:00 p.m., and a self-selected group where participants chose their own eight-hour schedule.
Sustained Weight Loss Across Eating Schedules
One year after the 12-week intervention concluded, both the early and late fasting groups had maintained significantly more weight loss compared to participants who continued eating across 12 hours or more each day. The early fasting group also preserved a larger reduction in fat mass. These findings indicate that the popular 16:8 approach—fasting for 16 hours and eating during an eight-hour window—produces effects that continue well beyond the structured program.
Dr. Alba Camacho Cardeñosa, a researcher at the University Joint Institute for Sport and Health (iMUDS) at UGR and a postdoctoral fellow at ibs.GRANADA (搜索) in the Endocrinology and Nutrition Department at San Cecilio University Clinical Hospital, served as the study's first author. "To date, although we knew that intermittent fasting promotes modest weight loss in the short term, it was unclear whether its effects were sustained over time," she explained. "By evaluating the participants 12 months after the intervention ended, we demonstrated that the changes in body weight persist."
Real-World Adherence and Flexibility
A particularly encouraging finding was that one in three participants decided to continue practicing intermittent fasting on their own during the year of follow-up. The researchers highlight that this suggests the regimen is "a relatively easy habit to integrate into daily life."
Because both early and late eating windows produced lasting benefits, patients may be able to choose the schedule that best fits their routines. This flexibility could improve adherence and enhance the usefulness of time-restricted eating in obesity (搜索) treatment.
Broader Research Context
This study is part of a larger project whose primary results were published in Nature Medicine, where it was observed that participants practicing time-restricted eating (TRE) lost an average of 3–4 kilos more than those who received only nutritional recommendations, regardless of when their eating window occurred.
The research was led by the PROFITH CTS-977 research group at UGR, headed by Professor Jonatan Ruiz Ruiz, in collaboration with San Cecilio University Clinical Hospital, Virgen de las Nieves University Hospital in Granada, the Public University of Navarra (搜索), the CIBER on Obesity (搜索) (CIBEROBN), and the CIBER on Frailty and Healthy Aging (CIBERFES). The MP20 group—Biomarkers of Metabolic and Bone Diseases at ibs.GRANADA (搜索)—continues to investigate intermittent fasting as a treatment for obesity and its comorbidities, alongside research into bone markers for predicting cardiovascular risk.
According to the research team, even a 12-week period of intermittent fasting may represent an effective medium-term strategy for weight control in overweight or obese adults. The findings offer valuable flexibility for patients and clinicians seeking sustainable, non-pharmacological approaches to obesity (搜索) management.