Copper

Among the more important trace elements is copper, which is present in many enzymes and in copper-containing proteins found in the blood, brain, and liver. Copper is important for preventing oxidative damage to cells through the enzyme superoxide dismutase. Deficiency is associated with the failure to use iron in the formation of hemoglobin and myoglobin. The adult DRI for copper is 900 micrograms per day, and the safe upper limit for adults is set at 10,000 micrograms per day. Excess consumption may result in GI distress or liver damage. Good sources of copper include shellfish, soybean products, legumes, nuts, seeds, liver, and potatoes. As another good example of why nutritional balance is important, excessive consumption of calcium, phosphate, iron, zinc, and vitamin C all reduce copper absorption.

Very few studies have been performed on the relationship between copper and athletic performance. Studies of blood copper concentrations in athletes and non-athletes have not revealed any significant differences, but the athletes have a slightly higher (3 to 4 percent) concentration of serum copper than do nonathletes. In a study evaluating the copper status of swimmers during a competitive season, there was no difference in pre- and postseason copper status. In this study, the majority of swimmers were consuming adequate levels of copper (more than 1 milligram per day) from food.