Glucosamine

Glucosamine is an amino sugar your body makes itself. It is a building block of glycosaminoglycans, the long sugars that keep cartilage hydrated, springy, and able to take pressure. Sold as glucosamine sulfate or hydrochloride at 1500 mg a day, it is one of the most popular joint supplements worldwide. Glucosamine partly blocks glycolysis, which mimics cutting carbohydrates. In worms and aging mice, that shift switched on AMPK, boosted mitochondria, and extended lifespan (about 8% in worms; significant in mice) (Weimer et al., Nature Communications 2014). A UK Biobank study of 495,077 adults (Li et al., Annals of the Rheumatic Diseases 2020) found glucosamine users had 15% lower all-cause death (HR 0.85, 95% CI 0.82 to 0.89) and 18% lower heart death (HR 0.82, 95% CI 0.74 to 0.90) over 8.9 years. But be careful with that finding. Suissa et al. (2022) showed these numbers likely reflect a statistical trap (collider bias) that can fake a 15 to 20% death reduction when the true effect is zero. No trial has tested glucosamine against a death endpoint. Guidelines back it only for painful knee osteoarthritis, where even the structural benefit is mixed.

Last reviewed: June 22, 2026

This definition is educational and is not medical advice, a diagnosis, or treatment. Talk to a doctor about any health decisions. Read our full medical disclaimer