If you, or someone you know is training for a marathon, adding extra iron to your diet may be a bad idea. New research recently published in the European Journal of Clinical Nutrition suggests that male recreational marathon runners may actually be at risk for iron overload. However, many athletes supplement their diets with iron. Why? A lack of iron in your system can leave you feeling sluggish and run-down. For runners, especially those training for long distances, this is a concern.
Iron is a key component of hemoglobin: the oxygen-carrying molecule that transports oxygen through the bloodstream to cells in need. Therefore, iron deficiency and, more severely, anemia, can hinder athletic performance. However, it turns out that iron deficiency may be a gender issue.
The study, conducted on 170 male and female adult recreational marathoners in Switzerland, showed that iron deficiency was found in 28 percent of female runners, but in less than 2 percent of male runners. Additionally, one in six male runners actually showed signs of iron overload, leading researchers to conclude that excess body iron may be common in male runners. (Women are at lower risk of iron overload due to monthly menstruation and their subsequently higher needs for dietary iron.) Therefore, males who supplement with iron may actually be at risk for iron overload. As a result, the researchers recommend that male runners should only use iron supplements if they have confirmed an iron deficiency through blood testing.
Iron overload is a condition that can become chronic; it develops over time as excess iron builds up in organ tissues like the heart and liver. In severe cases, it can lead to life-threatening liver or heart damage. And unfortunately, there is no distinct set of symptoms that indicate overload, though early symptoms include diarrhea, constipation, stomach discomfort and/or nausea. In more severe cases, weakness and fatigue, weight loss, and joint pain may occur. Blood tests done at routine doctor’s visits don’t test for iron overload, though an additional blood test can check for the condition.