Brazil's obesity drug surge sparks metabolic health warnings

Weight‑loss injections such as semaglutide (Ozempic, Wegovy) and tirzepatide (Mounjaro) have become commonplace in Brazil, offering substantial reductions in body weight. Doctors, however, caution that shedding pounds does not automatically restore overall health. Alexandre Duarte, a metabolic physiologist, said, "We have medicines that can produce weight loss that was previously seen only with invasive procedures. The problem begins when society believes that weight loss and health are exactly the same thing. They are not."

Clinical observations show that up to 30% of patients are "non‑responders," losing less than 5% of weight after six months. Lack of response can stem from improper dosing, early discontinuation, insulin resistance, poor sleep, concurrent medications that cause weight gain, or genetic variants—about 10% of individuals carry a gene that makes the hormone mimic ineffective. Women tend to respond better, likely due to higher estrogen levels that improve insulin sensitivity.

Experts stress the need to monitor metabolic markers—insulin sensitivity, inflammation, muscle mass, and hormonal balance—rather than relying solely on the scale, to ensure true health benefits beyond cosmetic weight loss.