"Even After Losing 16kg with Wegovy, Weight Returns Within a Year After Stopping the Drug"

Oxford University Research Team Finds
"Weight Regain Occurs Faster Than After Typical Diets"

A recent study has found that even if individuals successfully lose weight using medications such as Wegovy, they tend to regain the lost weight within a year after stopping the medication.

A notice saying "Wegovy In Stock" is posted at a pharmacy in Jongno-gu, Seoul. Photo by Kang Jinhyung

According to the British daily The Guardian on May 14 (local time), a research team from the University of Oxford recently presented the results of an analysis of 11 studies on GLP-1 (glucagon-like peptide-1), the key ingredient in drugs like Wegovy, at the European Congress on Obesity.

The researchers conducted their study on 6,370 adults who took GLP-1 medications, based on eight randomized controlled trials and three observational studies. Among these participants, 1,465 patients were taking Novo Nordisk's Wegovy (semaglutide) and Eli Lilly's Mounjaro (tirzepatide), both recommended for weight loss.

The study found that, on average, patients succeeded in losing 8 kilograms through medication, but regained their original weight within 10 months after discontinuing the drugs. Those who took Wegovy and Mounjaro lost an average of 16 kilograms?twice the overall average?but regained 9.6 kilograms within a year. This means they returned to their original weight in about 20 months.

The research team also analyzed the effectiveness of various non-pharmaceutical diets. In these cases, it took at least five years for participants to regain their previous weight. While weight regain was observed after successful dieting, the rate was much slower than with weight loss achieved through medication.

Susan Jebb, a co-author of the study and professor of diet and population health at the University of Oxford, explained, "Weight loss medications are highly effective, but when you stop taking them, weight regain occurs much more quickly than after stopping a typical diet."

Tom Fry, president of the Obesity Society of America, commented on the findings, saying, "It is not surprising that weight is regained when people use GLP-1 medications without seriously improving their lifestyle," and added, "Using GLP-1 is not as effective a solution as many users believe."

There are also calls to reduce dependence on weight loss medications in obesity treatment. Jane Ogden, professor of health psychology at the University of Surrey, advised, "People will need psychological counseling, behavior change, and nutritional support to maintain healthier behaviors and reduce weight in the long term." Jason Halford, president of the European Association for the Study of Obesity, also emphasized, "Weight loss medications are an adjunct to behavior change, not a replacement. We need to support patients in improving their lifestyles to maintain the effects of treatment."