“While it’s an association and not proof of causality, it does raise an important clinical question that now deserves much more attention,” researcher Matt Gentry said in a news release. He’s chair of biochemistry and molecular biology at the University of Florida.

Glucosamine is a natural compound found in healthy cartilage, which is the connective tissue that cushions joints, according to the Arthritis Foundation.

Glucosamine supplements are thought to reduce knee inflammation and protect cells that maintain cartilage structure, the Arthritis Foundation says.