Successful Aging: A Neuroscientist Explores the Power and Potential of Our Lives

by Daniel J. Levitin

Glucosamine is commonly taken by older adults for arthritis, but the scientific results are actually inconclusive. In the United States it is considered a “dietary supplement,” not a drug, and so its manufacture and use are not regulated, and it is illegal to advertise it for medical conditions. As with many supplements, its popularity is based on unsubstantiated claims infused with a lot of technical jibber-jabber that only superficially resembles scientific language and is carefully designed to persuade naive consumers. Glucosamine is a natural compound found in cartilage—the tissue that cushions joints. Some cases of osteoarthritis involve a breakdown of cartilage, so why not take cartilage in a pill? Well, there is no evidence that ingesting glucosamine actually affects its levels in joints. It might, or it might not. It’s sort of like saying that if you have liver disease, you should just eat a lot of calf’s liver and it will restore your own. The body doesn’t work like that. Nevertheless, aggressive advertising and claims surrounding glucosamine have made it a $15-billion industry in the United States alone.