Glucosamine Linked to Faster Cognitive Decline in Dementia

A new study has found that taking the common joint supplement glucosamine is associated with a significantly higher risk of accelerated cognitive decline and mortality in people with Alzheimer's disease or mild cognitive impairment. The research, published on June 9, 2026, in the journal Nature Metabolism, suggests the popular over-the-counter product may be harmful to brains already experiencing neurodegeneration.

The retrospective analysis, led by neuroscientists at the University of Florida, examined de-identified electronic health records from the UF Health system spanning from 2012 to 2024. Using artificial intelligence, researchers analyzed data from approximately 24,000 patients with Alzheimer's disease and related dementias (ADRD) and 41,000 patients with mild cognitive impairment (MCI). They found that about 8% of these patients reported taking glucosamine.

After controlling for factors like age, sex, and demographics, the analysis revealed a strong association. For patients with MCI, taking glucosamine was linked to a 25% higher likelihood of progressing to full dementia. For those already diagnosed with ADRD, glucosamine use was associated with a 25% increase in...