On Jan. 20, 2025, an analysis of data from nearly 2 million people has revealed new insights into the effects of obesity drugs — including the risks they pose.

The findings confirm that these drugs, called glucagon-like peptide-1 (GLP-1) receptor agonists, offer more than just weight-loss benefits. But the work highlights newly recognized risks of the medicines, including an increased likelihood of developing arthritis and a potentially deadly condition called pancreatitis.

Over about 3.5 years, the research team tracked more than 200,000 people with diabetes on GLP-1 drugs and about 1.7 million people with diabetes using other blood-sugar-lowering medications. They tracked the effects of GLP-1 drugs on 175 health conditions.

Compared with other diabetes medications, GLP-1 drugs were linked to a lower risk of dozens of conditions, including heart disease, stroke and kidney disease. They also lowered the risk of psychotic disorders by 18%, Alzheimer’s disease by 12%, and addiction disorders by an average of 13%.

But the study found risks associated with the GLP-1 use. For example, these drugs were associated with an 11% increase in arthritis risk and a 146% higher risk of pancreatitis — an inflammation of the pancreas that can lead to life-threatening complications. The study was published in Nature Medicine.