A joint is the connection between two bones. Joints and their surrounding structures allow you to bend, wiggle, turn etc.
Smooth tissue called cartilage and synovium and a lubricant called synovial fluid cushion the joints so bones do not rub together.Factors such as increasing age, injury, or carrying too much weight can wear and tear your cartilage. This can lead to a reaction that can damage your joints and lead to arthritis.
Joint health supplements can help keep the cartilage in joints healthy and may have an anti-inflammatory effect.