Millions Take This Joint Supplement — but It’s Linked to Faster Alzheimer’s Decline

Glucosamine is widely taken for joint pain and osteoarthritis, particularly by older adults. New research has linked its use among people with cognitive impairment to faster progression toward dementia and poorer survival after an Alzheimer’s-related dementia diagnosis.

The findings are important but not definitive. The human evidence comes from retrospective medical records and shows an association, while experiments in mice provide a possible biological explanation rather than proof that the supplement causes the same effects in people.