Male blood donors have a reduced risk of acute myocardial infarction compared with men who do not give blood, according to findings from eastern Finland. High body iron stores have been suggested as a risk factor for acute myocardial infarction, a hypothesis that could partly explain the lower incidence of coronary heart disease in premenopausal women, who lose iron through menstruation.
Blood donors had an 88% reduced risk of acute myocardial infarction compared with those who did not give blood. Other experimental, clinical and epidemiologic findings support the idea that high iron is harmful and low iron is beneficial for risk of coronary disease. Iron could accelerate progression of atherosclerosis through its ability to catalyse free radical production, and blood donation might both reduce body iron stores and stimulate production of younger erythrocytes that leak less iron than older red blood cells.
Am J Epidemiol 1998;148:445-451.
COMMENT: This report should highlight the observation that iron supplements are not your friend. The only people who should ever consider them would be women who had heavy menstrual bleeding or someone who had a bleeding ulcer. Even then, it would probably be far better to eat red meat as it is a far superior form of iron. There are many people whose high iron levels contribute to their heart disease.
The simple screening test for this is a serum ferritin. Ferritin is an iron transport protein and should be somewhere about 50. Levels below 20 indicate iron deficiency and above 80 a need to reduce iron levels through blood donation or therapeutic phlebotomy. If a person has an inflammatory disease like rheumatoid arthritis, though, the ferritin will be falsely elevated so it can not be properly evaluated.