and interfere with non-heme iron absorption. For example, an athlete who consumes milk or tea with beans at lunch could be advised to replace this beverage with citrus fruit juice to enhance iron absorption at that meal (44). In some cases, vegetarian athletes may temporarily require supplements to build up or maintain iron stores. Athletes taking iron supplements should have iron status monitored due to the potential association between iron status and chronic disease (46).Zinc.Several studies have reported altered zinc status in heavily-training athletes which is of particular concern when coupled with reportedly low zinc intakes in some athletes (47). Manore, however, has cautioned that apparent changes in zinc status due to exercise may be transient, and measurements of plasma zinc during heavy training periods may not reflect zinc status (48). Although little is known regarding the zinc status of vegetarian athletes, one should have some concern since the absorption of zinc from plant foods is somewhat lower than from animal products due to higher phytate concentrations of plant foods (49). Vegetarian sources of zinc include legumes, hard cheeses, whole grain products, wheat germ, fortified cereals, nuts, tofu, and miso. Although more research is needed in this area, published studies have found that zinc supplementation does not influence zinc levels during training (48,50) and has no apparent benefit on athletic performance (50).B vitamins. Vegetarian diets can provide the requirements for most B vitamins. Depending on the type of vegetarian diet, however, riboflavin and vitamin B12 are potential exceptions. Several studies have suggested that riboflavin needs may be increased in individuals with marginal riboflavin status who begin an exercise program (51, 52). Since riboflavin intakes are reportedly low in some vegans (5), active vegetarians who avoid dairy products should be educated on plant sources of riboflavin to ensure adequate intake. Plant sources of riboflavin include whole grain cereal, soybeans, dark green leafy vegetables, avocado, nuts and sea vegetables. Vitamin B12 has been of interest to athletic performance possibly due to its function in maintaining the cells of the hemopoietic and nervous systems. In fact, injections of B12 are still used by some athletes/coaches because of the belief that oxygen delivery is increased which in turn will enhance endurance. However, in the absence of actual deficiency, studies have failed to demonstrate any benefit of this practice (53) or of high-dose supplementation with a multivitamin (54). Since cobalamin, the active form of B12, is found exclusively in animal products, vegan athletes need to regularly consume B12 fortified foods which include Redstar brand (T6635) nutritional yeast, and those brands of soymilk, breakfast cereals and meat analogs that are B12 fortified. Vegetarians who consume eggs, cheese, milk or yogurt receive an ample supply of this vitamin.Antioxidant Vitamins. Increasing evidence suggests that vitamins C and E and -carotene may protect against exercise-induced "oxidative stress". Several recent reviews have summarized the current understanding of the potential benefits of antioxidant supplements in protecting against free radical production and lipid peroxidation (55,56) In brief, supplementation with antioxidants appears to reduce lipid peroxidation but has not been shown to enhance exercise performance