Over half of adults could be overweight by 2050. Why weight loss drugs aren't a cure

Over half of all adults — and a third of children and young adults — around the world are expected to be overweight or obese by 2050, according to a new study published Monday in the scientific journal The Lancet.

In 2021, roughly half of all adults worldwide — one billion men and 1.11 billion women over the age of 25 — were overweight or obese. If current patterns continue, those rates are expected to climb to 57% for men and 60% for women by 2050.

The trend is also accelerating among younger populations, with projections showing that by the middle of the century, one in three people between the ages of 5 and 24 will be affected. Researchers analyzed global data from 204 countries to make their projections.

This rise is expected to drive an increase in non-communicable diseases such as diabetes, cardiovascular disease, and cancer.

The study comes as sales of GLP-1 weight-loss drugs like Novo Nordisk’s (NVO-1.79%) Wegovy and Eli Lilly’s Zepbound continue to soar. The researchers did not factor these medications into their projections, citing a “lack of reliable long-term effect size information.” While they acknowledged the drugs could have some impact, they stressed that medications alone would not be enough to curb the crisis.

Here are the key reasons why the weight loss drugs might not be a cure-all for the global obesity epidemic.

GLP-1 weight loss drugs remain inaccessible

Despite their popularity, weight-loss medications face significant barriers that limit their potential to reverse the global obesity epidemic. The study’s authors pointed out that their effectiveness varies widely from person to person — and they remain difficult to access, especially in lower- and middle-income countries.

In 2023, a proposal to add anti-obesity medications to the World Health Organization’s essential medicines list, which would have broaden their access, was rejected due to concerns over long-term safety risks.

The fastest-growing obese populations aren’t taking GLP-1s

By 2050, the countries with the highest numbers of overweight or obese people will be China at 627 million, India with 450 million, and the United States with 214 million, according to the study.

But one of the most dramatic increase is expected in sub-Saharan Africa, where the number of overweight or obese people is projected to grow by more than 250% to 522 million.

However, the U.S. remains is the largest market for weight-loss drugs. In 2024, about 80% of Novo Nordisk’s sales of Wegovy were made in the U.S.

The study’s authors concluded: “[T]he sustainability and scalability of anti-obesity medications as a remedy to the global obesity epidemic are doubtful; public health interventions will remain key strategies in tackling the crisis.”