Health Supplement

• Iron and heart disease. Some evidence suggests that iron can stimulate the activity of free radicals. Free radicals are natural by-products of oxygen metabolism that are associated with chronic diseases, including cardiovascular disease. Free radicals may inflame and damage coronary arteries, the blood vessels that supply the heart muscle. Other researchers suggest that iron may contribute to the oxidation of LDL (“bad”) cholesterol, changing it to a form that is more damaging to coronary arteries. Numerous ways has been done to test an association between iron stores and coronary heart disease. But with conflicting results, and different methods to measure iron stores, make it difficult to reach a final conclusion on this issue.
• Iron and intense exercise. Many people who engage in regular, intense exercise such as jogging, competitive swimming, and cycling have marginal or inadequate iron status. Possible explanations include increased gastrointestinal blood loss after running and a greater turnover of red blood cells. Also, red blood cells within the foot can rupture while running. For these reasons, the need for iron may be 30% greater in those who engage in regular intense exercise.
• Iron and mineral interactions. Some researchers have raised concerns about interactions between iron, zinc, and calcium. When iron and zinc supplements are given together in a water solution and without food, greater doses of iron may decrease zinc absorption. However, the effect of supplemental iron on zinc absorption does not appear to be significant when supplements are consumed with food. There is evidence that calcium from supplements and dairy foods may inhibit iron absorption, but it has been very difficult to distinguish between the effects of calcium on iron absorption versus other inhibitory factors such as phytate.

Source: http://ods.od.nih.gov/factsheets/iron.asp