Intermittent Fasting May Offer an Easier Path to Weight Loss Than Calorie Counting, Study Finds
核心洞察
An 18-month clinical trial found intermittent fasting and continuous calorie restriction produced similar weight loss of about seven kilograms at six months in adults with obesity (搜索).
Participants using intermittent fasting did not feel they needed to constantly monitor eating or count calories, unlike those on calorie-restricted diets.
The calorie restriction group reported that conscious control over eating accounted for approximately 15% of their weight loss.
More than 200 adults with obesity (搜索) participated in an 18-month randomized clinical trial comparing three dietary approaches, and the results suggest that intermittent fasting may help people lose weight without the constant vigilance required by traditional calorie counting.
Researchers from the University of Adelaide and the South Australian Health and Medical Research Institute found that intermittent fasting and continuous calorie restriction produced similar weight loss after six months — an average of about seven kilograms in both groups, compared with approximately two kilograms in the standard care group. Yet the psychological experience of achieving that weight loss differed markedly between the two active dieting strategies.
"While many diets can result in weight loss, they may be difficult to stick to and this makes keeping that weight off long-term more challenging," said Professor Leonie Heilbronn from Adelaide University's School of Medicine and the South Australian Health and Medical Research Institute. "The results of our study indicate intermittent fasting could offer an alternative pathway for people who find conventional dieting challenging."
How the Trial Was Designed
Participants were randomly assigned to one of three groups: intermittent fasting, continuous calorie restriction, or standard care. Those in the intermittent fasting group consumed 30% of their daily energy needs between 8 a.m. and 12 p.m. on three non-consecutive days each week, followed by a 20-hour fast. On all other days, they ate their usual diet.
Participants assigned to continuous calorie restriction consumed about 70% of their normal calorie intake each day. The standard care group continued their regular diets but received healthy eating guidelines.
Divergent Psychological Pathways to Weight Loss
The findings, published in the journal Clinical Nutrition, indicate that the two active dieting strategies may promote weight loss through different psychological and behavioral mechanisms. Participants following the intermittent fasting plan did not feel they had to constantly monitor their eating, avoid overeating, or count calories to achieve their results.
In contrast, those in the calorie restriction group reported that losing weight required ongoing effort to consciously limit how much they ate and resist overeating. Researchers estimated that this increased sense of control accounted for about 15% of their weight loss.
"Psychological and behavioral effects have a major influence on people's abilities to adhere to diets. Intermittent fasting may help people achieve weight loss through ways that are less dependent on consciously restricting intake," said Professor Heilbronn.
Broader Impacts on Well-Being
Beyond weight loss, participants in both dieting groups reported improvements in depression and overall well-being, including on fasting days. The study examined not only how much weight people lost, but also how different dieting approaches affected eating habits, mood, sleep, and overall quality of life.
Implications for Personalized Weight Management
Although intermittent fasting has grown rapidly in popularity, researchers say much remains unknown about its long-term psychological and behavioral effects compared with more traditional dieting strategies. The study authors emphasize the need for further research to identify which individuals may benefit most from each approach.
"Future trials should be designed to identify individuals who struggle to improve eating behaviors, as they may do better with intermittent fasting diets, enabling more personalized weight management," said Professor Heilbronn.
The study was supported by the National Health and Medical Research Council Project Grant (APP1143092). Lead author Xiao Tong Teong was supported by an Australian Government Research Training Program Scholarship from The University of Adelaide.