Collagen is blend of amino acids that is an important part of the structure of the skin and keeps it firm. In a double-blind, placebo-controlled trial, 69 women aged 35-55 years were randomized to receive 2.5 g or 5.0 g of collagen or placebo once daily for 8 weeks. At the end of the study, skin elasticity in both collagen dosage groups showed a statistically significant improvement in comparison to placebo.