Intermittent fasting may not significantly boost weight loss, new review suggests
A research team examined 22 previous studies, encompassing nearly 2,000 adults, to determine whether short-term intermittent fasting (up to 12 months) helps people shed more pounds than standard diet advice or no guidance at all.
Intermittent fasting is a relatively recent weight-management approach that has surged in popularity. It includes several patterns, such as:
- restricting eating to a fixed daily window
- fasting on specific days of the week
- alternating between normal eating and very low intake on alternate days
When compared with conventional dieting guidance—like reducing overall calories and choosing healthier foods—the review found that intermittent fasting produced little to no difference in weight loss or quality of life for participants.
When matched against a control group that received no advice or was awaiting guidance on weight loss, intermittent fasting likewise showed minimal impact, though its effect on quality of life remained unclear.
The researchers described their confidence as “moderate” regarding weight loss outcomes when comparing intermittent fasting to no advice, but they were less certain about the other results.
A major caveat is that most of the included studies employed limited methods and involved small participant numbers, making it hard to determine true effects.
The review, published in the Cochrane Database of Systematic Reviews, calls for more research to explore how intermittent fasting might affect other health aspects—such as type 2 diabetes status and related conditions—and to assess how satisfied people feel with this approach.
There is a need for more detail on the various fasting types and how they might differently impact men and women, as well as individuals with different body mass indexes and from diverse countries.
The analyzed studies spanned Europe, North America, China, Australia, and South America.
Dr. Baptiste Leurent, an associate professor of medical statistics at University College London, commented that taken together, the studies “provide a clear indication that intermittent fasting offers little benefit.” He added that this aligns with a broader gap between public perception and scientific evidence.
Prof. Keith Frayn, emeritus professor of human metabolism at the University of Oxford, noted that intermittent fasting has been promoted as a way to boost weight loss due to claimed metabolic advantages. He observed that the study undermines such claims and emphasized that there are no quick fixes for overweight or obesity beyond simple calorie reduction.
The approach’s popularity among people seeking weight management remains evident, though the review did not specifically study its perceived ease or avoidance of weight gain.
In related weight-management trends, about 1.6 million adults in the UK are believed to be using injections like Wegovy and Mounjaro to lose weight—primarily via private prescriptions rather than through the NHS.
Recent findings also indicate that individuals who discontinue weight-loss injections may regain weight more rapidly than those who stop conventional dieting and exercise alone.
Would you be open to sharing your thoughts on intermittent fasting? Do you think this approach deserves a place in weight-management discussions, or should the focus remain on balanced calorie control and lifestyle changes? If you have personal experience or questions, feel free to join the conversation.
