Yucca schidigera, often called Mojave yucca, is a spiky desert plant that grows across the south-western United States and northern Mexico. Its trunk and roots are packed with saponins, natural soap-like compounds that foam when shaken with water. Indigenous peoples of the region used the root as a shampoo and soap, and also made use of the plant for food and fibre.
Today yucca extract has a surprising range of uses. It is added to animal feeds, used as a natural foaming agent in drinks, and sold in supplements, where it is traditionally used to support joint comfort. On a label you may see yucca, yucca root, Yucca schidigera extract or yucca stalk powder, usually in capsules or tablets and often in joint blends.
Beyond saponins, yucca contains polyphenols including resveratrol and compounds called yuccaols. Laboratory and animal studies have investigated their antioxidant and anti-inflammatory activity, and a few small human studies on joints were carried out in the 1970s. Modern clinical trials are lacking, so the interest in yucca for joints rests largely on tradition and early research.