The present invention relates to a composition comprising curcuminoid with green tea polyphenol or with a combination of glycine, proline and hydroxyproline for use in preventing or treating osteoarthritis. It also relates to a method of preventing or treating osteoarthritis in mammals, the method comprising administering to said mammal a composition which comprises curcuminoid with green tea polyphenol or with a combination of glycine, proline and hydroxyproline.