Designs For Health Pantothenic acid, also called vitamin B5, is a water-soluble vitamin used as a cofactor in many important biochemical reactions such as: acetyl-CoA synthesis and Kreb's cycle of energy production. Pantothenic acid is important for our bodies to properly use carbohydrates, proteins, and lipids and for healthy skin. It is naturally occurring in both plants and animals including meat, vegetables, cereal grains, legumes, eggs, and milk. After absorption, pantothenic acid is converted to a sulfur-containing compound called pantetheine. Pantetheine is then converted into co-enzyme A, which is the only known biologically active form of pantothenic acid.