For healthy skin, collagen is key: This naturally occurring protein keeps skin smooth and youthful, but our bodies produce less collagen as we get older. The result? Thinner skin, dryness, and more wrinkles.
Definition of BLACK BILE. : a humor of medieval physiology believed to be secreted by the kidneys or spleen and to cause melancholy. ADVERTISEMENT.1681. a humor of medieval physiology believed to be secreted by the kidneys or spleen and to cause melancholy. ADVERTISEMENT. 1681.
yellow bile. Thesaurus. Definitions of yellow bile. 1. n a humor that was once believed to be secreted by the liver and to cause irritability and anger. the liquid parts of the body.