TY - JOUR T1 - A–Z of nutritional supplements: dietary supplements, sports nutrition foods and ergogenic aids for health and performance: part 15 JF - British Journal of Sports Medicine JO - Br J Sports Med SP - 1202 LP - 1205 DO - 10.1136/bjsm.2010.078618 VL - 44 IS - 16 AU - D C Nieman AU - S J Stear AU - L M Castell AU - L M Burke Y1 - 2010/12/01 UR - http://bjsm.bmj.com/content/44/16/1202.abstract N2 - The most commonly used dietary supplements are micronutrients. The antioxidant properties of several dietary micronutrients are of particular interest to athletes due to the support of the body's endogenous antioxidant defence systems that allows free radicals to be neutralised to help decrease oxidative damage. Dietary antioxidants include vitamin C, vitamin E, carotenoids (mainly β-carotene), polyphenols (eg, flavonoids), selenium, glutathione and coenzyme Q10 (see part 3 of this series for an excellent overview of antioxidants). Due to the enhanced interest of the role of flavonoids in exercise, both in the media and scientific research, we have dedicated this issue to the topic: the very large number of flavonoids means that an exceptional number of citations is required. In this short review the potential bioactive effects of flavonoids and their efficacy as performance aids and countermeasures to exercise-induced oxidative stress, inflammation, delayed onset of muscle soreness (DOMS) and immune dysfunction are summarised. D C Nieman Phytochemicals are chemicals produced by plants, and include tannins, lignins and flavonoids. The largest and best studied polyphenols are the flavonoids, with more than 6000 identified and classified into at least six subgroups: flavonols, flavones, flavanones, flavanols (and their oligomers, proanthocyanidins), anthocyanidins and isoflavonoids (table 1).1 Flavonoids are widely distributed in plants and function as plant pigments, signalling molecules and defenders against infection and injury. View this table:In this windowIn a new windowTable 1 Flavonoid subgroups and food sources Dietary intake of flavonoids ranges from 50 to 800 mg/day depending on the consumption of fruits and vegetables and the intake of tea.2 3 In the USA, total flavonoid intake averages 210 mg/day,2 and in Spain 313 mg/day,3 with important sources including tea, citrus fruit and juice, beers and ales, wines, melon and berries, apples, onions and bananas. A high intake of fruits and vegetables has been linked in numerous studies to a reduced … ER -