A–Z of nutritional supplements: dietary supplements, sports nutrition foods and ergogenic aids for health and performance Part 9

Weight loss and muscle gain are physique goals pursued by many athletes, often with the hope that both will occur simultaneously! Part 9 of our series on dietary supplements includes summaries of three products which address these interests among other claimed benefits: choline bitartrate, chromium picolinate and cissus quandrangularis (CQ). Choline bitartrate is hypothesised to increase lipolysis, while CQ is claimed to have anabolic properties. Chromium picolinate is unique among dietary supplements, having been successfully marketed as both a muscle building and a fat loss supplement. While choline and chromium are both consumed from a range of dietary sources, CQ is a specific plant. The term adequate intake (AI) is used for the first time in this series, in the article on chromium picolinate. AI refers to the recommendations for dietary intake of a nutrient for which there is insufficient scientific evidence to establish requirements, since deficiency is rare. The observed intake is assumed to be greater than that required, and thus AI meets nutritional requirements. Chondroitin and glucosamine supplements are covered together because of their shared marketing for the support of bone and cartilage. ### J Pearce Choline is widely distributed in food fats, especially liver, egg yolk, peanuts, dairy products, human milk and phospholipids.1 The body synthesises choline, and a deficiency due to dietary inadequacy is unlikely. Choline is a precursor for the neurotransmitter, acetylcholine (which generates muscle contractions), and is a donor of methyl groups (lowering homocysteine levels, reducing heart disease risk). Lecithin, a natural source of choline, will be discussed under ‘L.’ Choline is promoted to athletes to improve physical endurance by increasing fat lipolysis and acetylcholine production to increase muscle contractions and delay fatigue. Choline supplements are thought to stimulate brain function (improving memory, intelligence and mood state in rats). Cyclists taking 2.34 g of choline showed …