Intermittent fasting: Why doctors say the diet trend doesn’t deliver

For years, intermittent fasting has been touted as a revolutionary approach to weight loss, promising not just a slimmer physique but also improvements in overall health. From social media trends to celebrity endorsements, the practice – which involves cycling between periods of eating and voluntary fasting – has gained immense popularity. But a major new review is challenging those claims, suggesting that intermittent fasting may not be any more effective for weight loss than traditional dieting, or even no structured diet at all.

The comprehensive analysis, published on February 18, 2026, and conducted by Cochrane researchers, examined data from 22 randomized clinical trials encompassing nearly 2,000 adults. The trials, conducted across North America, Europe, China, Australia, and South America, explored various intermittent fasting methods, including the 5:2 diet (fasting for two days a week), alternate-day fasting, and time-restricted eating. The findings, however, were consistent: intermittent fasting did not demonstrate a significant advantage over standard dietary advice or simply not following a specific diet when it came to weight loss.

“Intermittent fasting just doesn’t seem to work for overweight or obese adults trying to lose weight,” stated Dr. Luis Garegnani, director of the Universidad Hospital Italiano de Buenos Aires Cochrane Associate Center, in a statement released alongside the review. This conclusion echoes recent findings from a review published by Fox News, highlighting the lack of substantial difference in weight loss outcomes.

The rise of intermittent fasting coincided with growing concerns about global obesity rates. According to the World Health Organization, approximately 2.5 billion adults were overweight in 2022, with 890 million living with obesity. This public health crisis has fueled the search for effective weight management strategies, and intermittent fasting quickly emerged as a popular contender. However, this new evidence suggests that the appeal may be largely based on anecdotal experiences and social media hype rather than robust scientific data.

So, what does this mean for those currently practicing intermittent fasting, or considering it? Experts emphasize that while the review doesn’t necessarily invalidate the practice for everyone, it does temper expectations. It’s crucial to understand that weight loss is a complex process influenced by a multitude of factors, and there’s no one-size-fits-all solution.

“The best diet is the one that works for you,” explains Dr. Rachael Taylor, director of the Edgar Diabetes and Obesity Research Centre at the University of Otago. She stresses the importance of focusing on a diet rich in “real,” unprocessed foods. A personalized approach, guided by a healthcare professional, is often the most effective strategy.

Several experts highlight the importance of distinguishing between weight loss and overall health. Dr. Fiona Willer, lecturer in nutrition and dietetics at Queensland University of Technology, points out that the methods people use to lose weight can sometimes be detrimental to their health. Focusing solely on weight loss without considering the broader impact on well-being can be counterproductive.

Professor Luigi Fontana, scientific director at the Charles Perkins Centre RPA Clinic, University of Sydney, emphasizes that simply restricting when you eat doesn’t address the underlying factors contributing to weight gain. He cautions against extreme diets that can disrupt the gut microbiome and lead to nutrient deficiencies.

Beyond dietary choices, the review underscores the critical role of exercise. Experts agree that physical activity is essential for preserving muscle mass during weight loss and maintaining long-term weight management. Dr. Melyssa Roy, a public health physician and senior lecturer in medicine at the Otago Medical School, University of Otago, notes that her research demonstrates a strong link between physical activity and successful weight loss outcomes.

“Exercise is independently health promoting and critically important for preserving muscle mass during periods of energy deficit,” Roy explains. “Any recommendation that focuses solely on when or how much people eat, without addressing movement, is incomplete.”

awareness of hidden calories in processed foods is crucial. Dr. Clare Collins AO, professor in nutrition and dietetics at the University of Newcastle, suggests that many individuals underestimate the energy density of certain foods, which can sabotage their weight loss efforts. Making informed food choices and prioritizing whole, unprocessed foods are key components of a sustainable and healthy lifestyle.

the latest research serves as a reminder that there are no quick fixes when it comes to weight loss and health. A holistic approach that combines a balanced diet, regular physical activity, and personalized guidance from a healthcare professional is the most likely path to long-term success. While intermittent fasting may work for some individuals, it’s not a guaranteed solution, and its benefits should be viewed with realistic expectations.