Popular weight-loss injections used by millions in the UK can age the body by up to ten years and significantly raise the risk of frailty, a major new review has warned.
The Muscle Mass Dilemma
The report, commissioned by fitness company Les Mills and led by Dr Gillian Hatfield of Canada's University of the Fraser Valley, reveals a critical side effect. While the jabs are effective for weight reduction, they can dangerously deplete lean body mass, which includes muscle. This loss is not merely fat; studies indicate that between 20 and 50 per cent of the weight lost by users typically comes from other tissues.
Dr Hatfield's analysis found the scale of this muscle depletion is severe. "This magnitude of lean body mass loss is similar to bariatric surgery, cancer treatment, or approximately ten years of ageing," she stated. For the approximately 2.5 million people in the UK using these medications, this presents a hidden health crisis, particularly for middle-aged and older adults.
Increased Frailty and Fall Risk
The erosion of muscle and bone mass is especially alarming for older demographics, who naturally experience a decline in these areas with age. The report warns directly that this drug-induced loss "may increase frailty and risk of falls." Even individuals who maintained a regimen of 150 minutes of weekly exercise alongside a calorie deficit were not immune, with one study showing they still lost around 11 per cent of lean mass.
Bryce Hastings, Head of Research at Les Mills, emphasised the urgent need for a proactive fitness response. "Regular strength training is vital to our health at all stages of life, but this is especially true for people taking weight-loss medications," he said.
A Call for Integrated Support
The review, among the first to scrutinise the impact of these drugs on muscle composition, issues a clear recommendation. People using the injections should undertake strength training exercises two to three times per week, coupled with the standard 150 minutes of moderate to vigorous aerobic activity.
This combined approach helps preserve muscle during treatment and can lessen weight regain afterwards. The report concludes with a powerful call to action, urging the Government, the health sector, and the fitness industry to collaborate in order to better support the millions navigating this treatment path.
