Weight Loss Jabs May Lead to Rapid Weight Regain After Discontinuation

A new study indicates that individuals using obesity medications may experience significant weight regain within a year of discontinuing the treatment. Researchers at the University of Cambridge observed that, on average, participants had regained 60% of the weight lost after 52 weeks of stopping the drugs.

Health Implications of Weight Regain

Experts caution that if the regained weight is primarily fat, patients could “be worse off than before” they began the treatment. This shift might negatively impact their fat-to-lean mass ratio, potentially harming overall health.

“Our projections show that even though people regain most of the weight they have lost, they still maintain some of the weight loss. However, what we currently don’t know is if the same proportion of lean mass is recovered,” said Brajan Budini, a medical student at the School of Clinical Medicine and Trinity College, University of Cambridge.

GLP-1 Receptor Agonists: Beyond Weight Management

Weight loss jabs, or GLP-1 receptor agonists, are designed to mimic the hormone GLP-1, which helps control blood sugar and insulin levels. Initially developed for type 2 diabetes, drugs like semaglutide (Wegovy) and tirzepatide (Mounjaro) are now used on the NHS for obesity treatment.

A separate U.S. study, analyzing over 600,000 veterans with type 2 diabetes, found that these injections could also reduce risks of substance misuse. Participants without prior addiction histories saw a 14% lower likelihood of developing substance use disorders (SUDs) after starting the treatment.

The research also highlighted a 18% reduction in alcohol-related issues, 14% in cannabis use, 20% in cocaine dependence, and 25% in opioid misuse among those on GLP-1 drugs. For individuals already addicted, the jabs were linked to a 31% decrease in emergency department visits, hospitalizations, and overdose incidents.

Long-Term Weight Loss Potential

The Cambridge study, encompassing six trials with more than 3,200 participants, noted that weight regain tends to stabilize over time. By 60 weeks, the majority of lost weight—around 75%—was recovered, leaving a 25% reduction potentially sustainable in the long term.

Further research is recommended to understand how these drugs influence weight composition during and after therapy. The findings were published in eClinicalMedicine, emphasizing the need for ongoing exploration of their effects.

Read more: GPs to be offered bonus for prescribing jabs | Which weight loss jabs are available on the NHS? | Weight loss jabs could be banned by next Olympics