King and Xiang merged these data with 2015 mortality figures.
King himself takes glucosamine/chondroitin, one of the most common formulations of glucosamine supplements."One day I asked the other cyclists if they took glucosamine, and everyone did.
He explains that because this is an epidemiological study -- rather than a clinical trial -- it doesn't offer definitive proof that glucosamine/chondroitin makes death less likely.