America is embarking on a risky experiment with GLP-1s and aging

Over 10% of Americans use GLP-1 medications for weight loss, with an increasing number of older adults joining this trend. As more individuals start using GLP-1 receptor agonists like Wegovy, the number of older adults on these medications is predicted to rise significantly.

Recently, the Trump administration introduced the Medicare GLP-1 Bridge program, which aims to reduce the cost of three weight-loss drugs—Wegovy, the KwikPen version of Zepbound (tirzepatide), and Foundayo (orforglipron)—to $50 monthly. This could be beneficial for the 38.9% of U.S. adults aged 60 and older living with obesity but also introduces concerns about the long-term effects of these drugs on aging individuals.

Historically, treating obesity in older adults safely has been challenging, and while GLP-1s have been approved for weight loss, the evidence supporting their use in those over 60 remains limited. People in their 70s might gain as much from weight loss as younger individuals, but their reaction to the drugs’ side effects could differ. Experts caution that more research is needed to draw definitive conclusions.

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“Eligibility doesn’t mean benefit automatically,” explains Ruchi Gaba, an associate professor of endocrinology at Baylor College of Medicine. “We have to individualize.” Within the 60-and-older demographic, there’s significant diversity: a fit 68-year-old with obesity and sleep apnea differs vastly from an 88-year-old who is frail and at risk of falls, Gaba notes.

Older adults are often underrepresented in GLP-1 drug trials. Despite the high obesity rates in this group, only about 10% of early trial participants were 65 or older, according to Alissa Chen, a primary care physician and obesity researcher at Yale School of Medicine. Older adults display more variability in chronic conditions and medications than younger groups, which complicates both prescriptions and side effects management, Chen says.

“We need to be more critical about who we’re starting on these medications and thinking about all those chronic conditions and thinking about those medicines, thinking about the benefit there is to be gained,” she says. “We have to think about ‘What does weight loss get us in that age group?’”

GLP-1 drugs mimic the glucagonlike peptide 1 hormone, naturally released after eating to signal fullness. This hormone prompts insulin release, suppresses glucagon—which prevents excessive sugar release into the bloodstream—and slows gastric emptying, leading to prolonged satiety and weight loss.

While GLP-1s typically don’t interact with other drugs, their effects can lead to cascading risks, Gaba states. Slow gastric emptying could exacerbate constipation—a common issue in older adults—and might also cause nausea and vomiting, potentially resulting in dehydration. Dehydration, in turn, can lead to orthostatic hypotension and falls for those on blood pressure medications. Diabetics on sulfonylureas face increased hypoglycemia risks when using GLP-1s, according to Gaba.

Another concern is lean muscle loss, a recognized side effect of GLP-1s, which heightens the risk of injury from falls in older adults. Moreover, older individuals may respond differently to these medications due to varied body compositions and diminished liver and kidney functions.

Chen suggests that functional ability, not just weight, should guide GLP-1 prescriptions. “Success for a senior might mean being able to walk longer distances without knee pain or getting on the floor to play with their grandchildren,” she says. “If a senior loses weight but also loses significant muscle mass, is the treatment really a success?”

GLP-1s are intended for continuous use to prevent weight regain. The new Medicare program under the Trump administration is temporary, lasting 18 months. However, once initiated, discontinuing these drugs is not ideal, Chen notes. “These are medications that should be taken for the long term.”

Chen is often hesitant to prescribe these drugs if a patient is already maintaining a healthy diet and exercise routine. “We know exercise is very good at keeping people healthy and helping them live long and improving cardiovascular fitness,” she says.

The aim of weight loss is to achieve similar benefits. But if a patient is already making choices that enhance those outcomes, Chen questions the additional benefit of further weight loss.

For those with other health conditions, evidence suggests GLP-1s can enhance healthspan, potentially affecting lifespan. Nonetheless, for those over 65, lifestyle interventions remain the primary strategy for managing obesity.

Although GLP-1 drugs are often used as long-term maintenance therapy because stopping them commonly leads to weight regain, there is still limited data on their effects over a full lifespan in older adults, especially frail older adults. Analyses to date show that, in older adults, GLP-1 drugs are associated with fewer cardiovascular events and, in some studies, lower all-cause mortality. But there is no direct evidence that they extend lifespan.

Chen’s research shows that side effects can affect up to 40% of weight-loss drug users. Older adults often discontinue treatment due to these side effects, and upon stopping, they typically regain lost weight, which may worsen conditions like cardiovascular disease or type 2 diabetes.

To ensure regained weight is muscle rather than fat, resistance exercises and higher protein intake are recommended. However, “if you’re not doing those things, you could be having higher adiposity after than you were before you ever started the medication,” Chen warns.