April 16, 2025
Popular weight loss drugs like Ozempic and Wegovy may cut the risk of Alzheimer’s disease and other forms of dementia, a large new analysis found. The findings build on growing evidence that the powerful drugs used to treat diabetes and obesity may have protective effects for the health of the brain as well.
Earlier studies have suggested that the drugs, known as GLP-1 receptor agonists, may lower dementia risk. This study was larger, pooling data from 26 different clinical trials involving more than 160,000 men and women with Type 2 diabetes who were taking various drugs to lower high blood sugar, or glucose. While most glucose-lowering therapies were not significantly associated with a reduction in dementia risk, the GLP-1 drugs were linked to a 45 percent reduction in the risk of Alzheimer’s disease and other forms of dementia.
“This research represents a significant contribution to our understanding of how some diabetes medications may impact brain health,” said Dr. Catriona Reddin, the senior author and a researcher at the University of Galway in Ireland. “Diabetes is a known risk factor for dementia, but whether glucose-lowering therapies can help prevent cognitive decline has remained unclear. Our findings suggest that GLP-1 receptor agonists, in particular, may have a protective effect on brain health.”
The findings, published in the journal JAMA Neurology, provide some of the best evidence to date that certain weight loss drugs may help to protect against Alzheimer’s disease. GLP-1s are given by injection and include such drugs as semaglutide, which has been used for more than 15 years to regular blood sugar in diabetes and is the active ingredient in the popular weight loss drugs Wegovy and Ozempic. Other, newer GLP-1 drugs include Mounjaro and Zepbound. A smaller analysis, also published in JAMA Neurology, found that GLP-1 drugs as well as a similar class of diabetes medications known as SGLT2 inhibitors may have benefits for brain health with regard to Alzheimer’s disease and related dementias.
Diabetes is a well-known risk factor for dementia, in part because high blood sugar levels can damage blood vessels throughout the body, including in the brain. Obesity, too, is a known risk factor for Alzheimer’s disease, in part because it is tied to high levels of inflammation throughout the body. Increasingly, researchers recognize the links between body-wide inflammation and Alzheimer’s disease. It is also possible that GLP-1 drugs can penetrate the blood-brain barrier and might aid in the clearance of beta-amyloid, the toxic protein that is a hallmark of Alzheimer’s disease.
GLP-1 drugs have been linked to a range of benefits beyond controlling diabetes and inducing weight loss. They have been tied to improvements in rates of heart, liver and kidney disease, and they may prolong lifespan. There have even been intriguing reports that they may help to control a range of addictive behaviors, including gambling, drinking, drug use, smoking and compulsive shopping.
More study is needed before these drugs can be recommended as a preventive measure against Alzheimer’s disease, or whether they might provide brain benefits to those who do not already have diabetes. Also, both studies had timelines that averaged less than three years, which is a relatively short period for the onset of dementia.
“Large trials should be conducted to specifically study the effect of glucose-lowering therapy on dementia and cognitive decline,” Dr. Reddin said. “There are a number of trials ongoing looking at the effect of glucose lowering medications on cognition.”
Whether you are taking weight loss drugs or not, experts stress the importance of regular physical activity and a heart-healthy diet to help maintain brain health. Obesity and diabetes are well known risk factors for Alzheimer’s disease, and taking steps to maintain good heart and metabolic health can go a long way in helping to keep the brain in good working order.
By ALZinfo.org, The Alzheimer’s Information Site. Reviewed by Eric Schmidt, PhD, of The Fisher Center lab at The Rockefeller University.
Sources: Allie Seminer, MSc; Alfradi Mulihano, Clare O’Brien, MD; et al: “Cardioprotective Glucose-Lowering Agents and Dementia Risk: A Systematic Review and Meta-Analysis.” JAMA Neurology, April 7, 2025
Hullin Tang, PhD; William. T. Donahoo, MD; Steven T. DeKosky, MD; et al: “GLP-1RA and SGLT2i Medications for Type 2 Diabetes and Alzheimer Disease and Related Dementias.” JAMA Neurology, April 7, 2025
