Ray Sahelian, M.D. Cellular Rejuvenation Muscle Vitality Doctor Formulated Dietary Supplement Formulated by Medical Doctor Ray Sahelian, M.D.  Bestselling Author and Nutrition Expert Carnosine is a small molecule composed of the amino acids, histidine and alanine and is found in relatively high concentrations in several body tissues.Advance Physician Formulas, Inc.