Collagen 23/07/2019 The collagen family of proteins is the most abundant in the human body, with a primary role as connective tissue. For example, it is found in tendons, ligaments and skin as well as bone, muscle tissues and blood vessels. Related Articles: InnovAAte Amino Acids: Women's healthCollagen and Soft TissuesThe importance of amino acids in chronic fatigue syndromeProductInnovAAte: Amino Acid Newsletter, Issue 3