TY - JOUR T1 - A–Z of nutritional supplements: dietary supplements, sports nutrition foods and ergogenic aids for health and performance: Part 46 JF - British Journal of Sports Medicine JO - Br J Sports Med SP - 809 LP - 810 DO - 10.1136/bjsports-2013-092699 VL - 47 IS - 12 AU - P A Deuster AU - A B Hodgson AU - S J Stear AU - L M Burke AU - L M Castell Y1 - 2013/08/01 UR - http://bjsm.bmj.com/content/47/12/809.abstract N2 - The concluding alphabetical part of our series, part 46, deals with just two topics for the letter ‘Z’. One of these, zinc monomethionine aspartate (ZMA), is a derivative of the other well-known supplement, zinc (Zn). Zn is widely used by both athletes and the general population. PA Deuster The essential trace mineral Zn serves multiple biological functions—catalytic, structural, regulatory and substrate1—in support of metabolic, endocrine, signal transduction, cellular control, protein stabilisation and immune networks/pathways.1 ,2 Overall, approximately 3000 Zn proteins are encoded in the human genome1 and Zn is a cofactor to more than 300 enzymes; these include superoxide dismutase, alkaline phosphatase and alcohol dehydrogenase, in the liver, and carbonic anhydrase III, AMP deaminase and the matrix metalloproteinases, in skeletal muscle. As one of the most widely distributed metals in the body, 85% of Zn resides in muscle and bones, 11% in skin and the liver and the remainder in all the other tissues.2 This clearly demonstrates the overall importance of Zn and would suggest that it may be important in physical performance. The best food sources of Zn are oysters, wheat germ, liver, beef, melon, squash seeds and cocoa. Improvement in physical performance or aspects of physical performance by administration of Zn can be demonstrated in one of three ways: (1) showing that providing Zn to persons who are Zn deficient restores/improves performance, (2) demonstrating that providing Zn to healthy individuals with adequate Zn status improves some aspect of performance or (3) showing that Zn supplementation counters a particular health risk that could compromise performance. Performance improvement in … ER -