Promising breakthrough: Widely-used diabetes drugs reduce dementia risk by up to 43%, sparking hope for Alzheimer’s care

Originally developed to manage blood sugar in type 2 diabetes, drugs like semaglutide — sold under brand names Ozempic and Wegovy — are now showing promise in a radically different realm: brain health. Two recent studies, suggest these medications may offer protection against dementia, a growing global health crisis. As researchers look for better, safer options beyond current Alzheimer’s drugs, attention is shifting toward these familiar, well-tolerated treatments with surprising potential.

Dementia, including Alzheimer’s disease and related disorders, is one of the fastest-growing public health concerns globally. It currently affects over 55 million people and is expected to impact 139 million by 2050, with the most significant increases in low- and middle-income countries. Alzheimer's remains the leading form of dementia, accounting for 60-70% of all cases.

New treatments like lecanemab and aducanumab have stirred debate due to safety concerns and limited effectiveness. This uncertainty has fueled growing interest in repurposing existing, widely used medications with known safety profiles — particularly GLP-1 receptor agonists and SGLT2 inhibitors.

A multi-cohort study by the University of Florida, analyzing data from over 90,000 patients, found that GLP-1RAs were associated with a 33% lower risk of developing Alzheimer’s and related dementias, while SGLT2is were linked to a 43% lower risk, compared to other diabetes drugs. While the difference between the two wasn’t statistically significant, both drug classes appeared to offer substantial protective effects.

A separate investigation led by the University of Galway added further weight. Reviewing 26 randomised clinical trials involving more than 164,000 participants, the researchers found a statistically significant association between GLP-1 receptor agonists and reduced dementia risk. Notably, this analysis did not observe the same benefit for SGLT2 inhibitors or pioglitazone, hinting that GLP-1RAs may have a uniquely protective impact on brain function.

Originally developed to regulate blood sugar and promote weight loss, GLP-1 receptor agonists like semaglutide target receptors found not only in the pancreas and gut, but also in the brain, heart, and immune system. In animal models, they’ve been shown to reduce brain inflammation, improve synaptic plasticity, and lower levels of amyloid-β and tau — hallmarks of Alzheimer’s pathology.

Major Phase III trials — EVOKE and EVOKE Plus — are now in progress to evaluate semaglutide in individuals with early Alzheimer’s, according to a MedicalXpress report. If successful, the results could transform how clinicians approach care for aging patients managing both diabetes and cognitive decline. However, GLP-1RAs are not risk-free. Common side effects include nausea, vomiting, and loss of lean muscle mass — a particular concern for older adults vulnerable to sarcopenia.