A recent study published in *Nature Metabolism* indicates that glucosamine, a popular over-the-counter supplement used for joint pain, may exacerbate memory loss in individuals with Alzheimer's disease. Researchers found that those with Alzheimer's who took glucosamine had a 25% higher risk of mortality within five years compared to non-users. Furthermore, individuals in the early stages of cognitive decline, known as mild cognitive impairment, were also 25% more likely to develop full-blown Alzheimer's when using the supplement. The study analyzed anonymized medical records from 24,000 patients with Alzheimer's and 41,000 with mild cognitive impairment. Mouse experiments revealed that glucosamine worsened memory loss while blocking sugar production improved symptoms. Although glucosamine is generally considered safe for healthy individuals, these findings raise concerns about its use among those with cognitive impairments. Researchers emphasize the need for further studies to explore the potential risks associated with glucosamine and its effects on cognitive decline.