Obesity rates are down. Is that because of weight-loss drugs?
Earlier this fall, the Centers for Disease Control and Prevention reported data showing that adult obesity rates—long trending upwards—had fallen modestly over the past few years, from 41.9 to 40.3 percent. The decline sparked discussion on social media and in major news outlets about whether the US has passed so-called “peak obesity”—and whether the growing use of certain weight-loss drugs might account for the shift.
An opinion piece in the Financial Times suggested that the public health world might look back on the current moment in much the same way that it now reflects on 1963, when cigarette sales hit their high point and then dropped dramatically over the following decades. The article’s author, John Burn-Murdoch, speculated that the dip is “highly likely” to be caused by the use of glucagon-like peptide-1 receptor agonists, or GLP-1s, for weight loss.
It's easy to see why one might make that connection. Although GLP-1s have been used for nearly two decades in the treatment of type 2 diabetes, their use for obesity only took off more recently. In 2014, the Food and Drug Administration approved a GLP-1 agonist named Saxenda specifically for this purpose. Then in the late 2010s, a GLP-1 drug named Ozempic, made from the active ingredient semaglutide, began to be used off-label. The FDA also authorized Wegovy, another semaglutide-based GLP-1 medication, explicitly for weight loss in 2021.