has a poor iron status, any additional iron loss from exercise may be enough to tip her over the edge into a more serious deficiency,\expert.
Exercise can result in iron loss through a variety of mechanisms. Some iron is lost in sweat, and, for unknown reasons, intense endurance exercise is sometimes associated with bleeding of the digestive system. Athletes in high-impact sports such as running may also lose iron through a phenomenon where small blood vessels in the feet leak blood. There are three stages of iron deficiency. The first and most common is having low iron reserves, a condition that typically has no symptoms. Fatigue and poor performance may begin to
appear in the second stage of deficiency, when not enough iron is present to form the molecules of blood protein that transport oxygen to the working muscles. In the third and final stage, people often feel weak, tired, and out of breath — and exercise performance is severely compromised. \they're not at the third stage, nothing is wrong, but that's not true,\John L. Beard, who helped design the Purdue study. %until your iron reserves go to zero, and if you wait until that point, you're in trouble.\
However, most people with low iron reserves don't know they have a deficiency, because traditional methods of calculating the amount of iron in blood (by checking levels of
the blood protein that transports oxygen) are not sufficient, Beard states. Instead, it's important to check levels of a different compound, which indicates the amount of storage of iron in the blood. While active, child-bearing age women are most likely to have low iron stores, he notes, \
especially if they don't eat meat and have a high level of physical activity.\of male long distance runners have low iron stores.) Beard and other experts say it's advisable for people in these groups to have a yearly blood test to check blood iron reserves.
If iron levels are low, talk with a physician to see if the deficiency should be corrected by modifying
your diet or by taking supplements. In general, it's better to undo the problem by adding more iron-rich foods to the diet, because iron supplements can have serious shortcomings. Supplements may produce a feeling of wanting to throw up, and may be poisonous in some cases. The best sources of iron, and the only sources of the form of iron most readily absorbed by the body, are meat, chicken, and fish. Good sources of other forms of iron include dates, beans, and some leafy green vegetables. \cereals with the words 'iron-added' on the label,\expert Nancy Clark. \supplements the small amount that naturally occurs in grains. Eat these foods with plentiful Vitamin C (for example, drink orange juice with
cereal or put a tomato on a sandwich) to enhance the amount of iron absorbed.\cooking in iron pans, as food can derive iron from the pan during the cooking process. \tomato sauce cooked in an iron pot for three hours showed a striking increase, the level going up nearly 30 times,\are likely to have low iron should avoid drinking coffee or tea with meals, she says, since substances in these drinks can interfere with iron being absorbed into the body.
\careful about their food choices,\sums up Purdue's Lyle. \attention to warning signs before iron reserves are gone, you can
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