Amino Pure Beauty 350gDoctor's Opinion on Glutamine and Beauty As women age, the body's collagen production drops rapidly, leading to sagging skin, a weakening skin tone, thinning hair, and brittle nails. AminoPure BUTty is formulated with the amino acid glutamine and helps the body produce collagen. It also improves skin elasticity and increases hair volume. Furthermore, you can experience improved gut health and immunity. Paul K. Shitabata, M. D., Clinical Professor at