Why Bone and Joint Health Declines with Age — And Why Supplements Matter To choose the right supplements, seniors and caregivers first need to understand the biology of what's happening inside ageing joints and bones. Cartilage degradation is the primary driver of joint pain in older adults. Cartilage — the smooth, rubbery tissue covering the ends of bones in every joint — has no blood supply of its own. It relies on synovial fluid for nutrients and gets physically compresse