A retrospective analysis of electronic health records reports that people who take glucosamine, a widely used supplement for joint pain, show worse outcomes related to cognitive decline. Across the study, glucosamine use is associated with faster progression to Alzheimer’s disease and poorer survival among people who already have Alzheimer’s. The Independent and MedPage Today both report that the risk increase is about 25% over roughly five years, including a higher likelihood of death among Alzheimer’s patients who use glucosamine compared with those who do not. ScienceDaily similarly describes findings indicating a higher likelihood of developing dementia and notes that researchers identify biological clues that may help explain the association, including mechanisms that could relate glucosamine exposure to disease progression. The study is observational, meaning it finds correlations rather than proving that glucosamine directly causes Alzheimer’s or affects survival. The findings nonetheless raise questions about the safety of glucosamine for people at risk of cognitive decline and prompt calls for further research.