Weight loss drug semaglutide shows benefits for adults over 65, study finds

Adults over 65 who took semaglutide, the active ingredient in the weight loss drugs Ozempic and Wegovy, lost substantially more weight than those given a placebo, according to a new analysis of clinical trial data. The study examined six trials known as the STEP program and focused specifically on older adults with obesity who did not have diabetes.

Researchers led by Prof Luca Busetto of the University of Padova in Italy analyzed data from 358 participants aged 65 and older. Of these, 248 received semaglutide at a dose of 2.4 mg once weekly, and 110 received placebo. The average age of participants was 69 years, with most between 65 and 74 years old. Women made up 72% of the group.

By week 68, participants taking semaglutide had lost an average of 15.4% of their body weight, compared with 5.1% in the placebo group. The differences in waist circumference were equally striking. Those on semaglutide saw their waist measurement drop by an average of 14.3 centimeters, while the placebo group experienced a decrease of 6.0 centimeters.

More older adults on semaglutide reached major weight loss goals. About two-thirds (66.5%) lost at least 10% of their body weight, compared with just 15.5% in the placebo group. Nearly half (46.8%) of semaglutide users achieved at least 15% weight loss, versus 6.4% on placebo. One in four semaglutide participants (28.6%) lost 20% or more of their body weight, compared with 2.7% on placebo.

Beyond weight, the drug improved several markers of heart and metabolic health. Among semaglutide users, 27% reached a body mass index of less than 27 kg/m², defined as healthy weight, compared with 5.5% on placebo. Participants also showed greater improvements in blood pressure, cholesterol, blood fats, and blood sugar control measures. These improvements matter because older adults with obesity often have multiple health conditions that raise their risk of complications.

The overall rate of side effects was similar between groups, with 89.1% of semaglutide users and 84.5% of placebo recipients reporting at least one adverse event. However, serious adverse events occurred more often in the semaglutide group, affecting 19% of participants compared with 12.7% on placebo. Constipation and dizziness, both known effects of this type of medication, were more common with semaglutide. Fractures and dangerously low blood sugar occurred in less than 1% of participants in both groups.

Prof Busetto stated: "In this analysis of individuals with obesity aged 65 years and older, semaglutide reduced body weight and improved cardiometabolic risk factors compared with placebo, and the safety and efficacy profile of semaglutide was consistent with that reported in the STEP program." He noted that in many countries, most obesity cases occur in adults over 65, making the findings relevant to public health policy.