People who stop taking the weight-loss jab Mounjaro (tirzepatide) are likely to regain weight and lose key health benefits such as improved blood pressure, cholesterol and blood sugar control, according to new research.
The findings come from the Surmount-4 clinical trial, where participants took tirzepatide for 36 weeks before being split into two groups: one continued the drug, while the other switched to a placebo. Of those who stopped the medication after significant weight loss, 82% regained at least a quarter of the weight they had originally lost within a year.
Researchers found that as weight returned, so did health risks. People who regained 75% or more of their lost weight saw their blood pressure, “bad” cholesterol, waist measurements and blood glucose levels return to pre-treatment levels.
Experts said the results were not surprising, as weight gain is closely linked to worsening cardiovascular and metabolic health. Professor Naveed Sattar of the University of Glasgow warned that stopping treatment may also remove protective effects against conditions such as heart failure.
The study highlights the challenge of long-term weight management. Experts noted that weight-loss drugs don’t always help people build lasting habits around diet and exercise, which can make maintaining results difficult once medication is stopped.
Separate research also suggested women who stop such drugs before or during pregnancy may face higher risks of complications, though experts caution more research is needed to confirm cause and effect.
Researchers concluded that long-term treatment and lifestyle changes are likely necessary to maintain both weight loss and associated health benefits.
