Researchers at the University of Florida analyzed health records of nearly 5,000 patients and found that glucosamine users with mild cognitive impairment were 25% more likely to progress to dementia. Those already diagnosed with Alzheimer's disease and related dementias who took glucosamine also faced a 25% higher mortality risk. Lab experiments in human brain tissue and mouse models suggest glucosamine may worsen an abnormal sugar-tagging process called glycosylation that is already dysregulated in the Alzheimer's brain. The findings, published in Nature Metabolism, are observational and do not prove cause and effect. Clinical trials are needed before any firm conclusions can be drawn, but the results raise important caution for the millions of older adults regularly taking this common over-the-counter supplement.
