Overweight adults who pursue Intermittent Fasting Weight Loss lose no more weight than those following traditional calorie‑restricted diets, according to a review of 22 clinical trials published Monday. The findings challenge claims that intermittent fasting provides unique metabolic benefits.
Review Of 22 Trials Finds No Added Weight-Loss Benefit
Researchers analyzed 22 randomized clinical trials involving 1,995 overweight or obese adults across North America, Europe, China, Australia, and South America. The study appears in the Cochrane Database of Systematic Reviews.
The review examined Intermittent Fasting Weight Loss approaches—including alternate‑day fasting, fasting on specific days of the week, and time‑restricted eating—against standard diets that reduce daily calorie intake.
Intermittent fasting did not produce clinically meaningful additional weight loss compared with traditional dieting based on a daily calorie deficit, the authors concluded.
Participants who fasted intermittently lost slightly more weight than control groups that made no dietary changes, about 3.4 percent on average. But researchers said that the difference does not demonstrate a special metabolic effect.
“Intermittent Fasting Weight Loss may be a reasonable option for some individuals, but the current evidence does not support the level of enthusiasm often seen on social media,” said Luis Garegnani, lead author of the study from the Universidad Hospital Italiano de Buenos Aires Cochrane Associate Centre. He noted that the approach delivers results “similar to traditional dietary methods for weight loss.”
Scientists Question Claims Of Unique Metabolic Effects
The researchers found no evidence that intermittent fasting triggers metabolic changes beyond reducing overall calorie intake.
“The main benefit appears to be simple calorie restriction,” the authors wrote, noting that claims of “special effects” tied to feast-and-famine cycles are not supported by current data.
Keith Frayn, emeritus professor of human metabolism at the University of Oxford, said the findings align with broader evidence on weight loss.
“There’s no convincing evidence of special effects on metabolism beyond simple restriction of calories,” Frayn said.
Still, outside experts cautioned against dismissing Intermittent Fasting Weight Loss entirely. Paul Garner, an expert in analyzing global health evidence at the Liverpool School of Tropical Medicine, noted that the trials did not focus on individuals who independently chose this method.
“None of the studies examine people who decide themselves to follow these diets, and who are therefore motivated to embark on intermittent fasting themselves,” Garner said.
Researchers also acknowledged limitations, including small sample sizes, inconsistent reporting, and limited data on patient satisfaction. They called for higher-quality studies to better assess long-term outcomes.
Obesity Rates Rise As Debate Over Best Strategies Continues
The findings come as obesity rates continue to climb worldwide. A 2024 study found adult obesity rates have doubled over three decades, with rates among children and adolescents rising nearly twice as fast.
The search for sustainable weight-loss strategies has intensified alongside the rise of new anti-obesity medications. While some drugs have produced significant weight loss, experts note they remain expensive and in limited supply.
Projections published last month suggest that people who stop taking the medicines often regain weight within two years and lose associated benefits to heart health, cholesterol levels, and blood pressure.
Adam Collins, associate professor of nutrition at the University of Surrey, said dieting studies can also be influenced by participant behavior.
Control group members who are told to make no changes may still alter their eating habits simply because they are being monitored, a phenomenon known as the Hawthorne effect.
“The sheer act of filling in food diaries or being weighed can lead people to change their eating behavior,” Collins said.
Researchers noted that Intermittent Fasting Weight Loss remains an option for people seeking structured ways to reduce calorie intake. However, they emphasized that current evidence does not show it is more effective than traditional dieting for achieving weight loss.
Visit Healthcare 360 Magazine For The Most Recent Information.
