Some clinical studies report that the oral ingestion of hydrolyzed collagen decreases joint pain, those with the most severe symptoms showing the most benefit.[8][9] Beneficial action is likely due to hydrolyzed collagen accumulation in the cartilage [3] and stimulated production of collagen by the chondrocytes, the cells of cartilage.[10] Several studies have shown that a daily intake of hydrolyzed collagen increases bone mass density in rats.[11][12] It seems that hydrolyzed collagen peptides stimulated differentiation and osteoblasts activity- the cells that build bone- over that of osteoclasts (cells that destroy bone).