Vitamins, Minerals and Dietary Supplements
What is iron?
Iron is an important trace mineral found in every cell of the body, usually in combination with protein. Depending on the level of iron in the body, it can act either as an antioxidant, or it can stimulate the formation of free radicals.
Why do we need it?
Iron is an essential nutrient because it is a vital part of red blood cells, which carry oxygen to all body cells. Iron is essential to the formation of hemoglobin and myoglobin, which carries the oxygen in the blood and muscles. It makes up part of many proteins and enzymes in the body.
How much iron should I take?
According to the National Academy of Sciences, the recommended daily allowance (RDA) of iron is as follows:
- Adult men: between 10-12 milligrams/day
- Adult women: 15 milligrams/day
- Children aged 7-10: 10 milligrams/day
- Infants: 10 milligrams/day
- Pregnant/lactating women: 30 milligrams/day
What are some good sources of iron?
Red meat, fish, poultry, eggs, legumes and fortified cereals are all good sources of iron. Other sources include oysters, dried fruits, molasses, and dark, leafy green vegetables such as broccoli and spinach.
The best food sources of easily absorbed iron are animal products. Iron from vegetables, fruits, grains, and supplements is harder for the body to absorb. Mixing lean meat, fish, or poultry with beans or dark leafy greens at a meal can improve absorption of vegetable sources of iron up to three times. Foods rich in vitamin C also increase iron absorption.
What can happen if I don't get enough iron?
Iron deficiency is the most common nutritional deficiency worldwide. Deficiency occurs in the form of iron deficiency anemia. Iron deficiency and anemia can occur during periods of rapid growth, during pregnancy, and among women who are menstruating more than usual. It can be associated with any type of intestinal loss of blood, frequent donation of blood, or from the inability to absorb iron efficiently. Initial symptoms of iron deficiency anemia are fatigue and lack of energy. Dizziness, weight loss, headaches and lowered immunity can also occur.
What can happen if I take too much?
Iron toxicity rarely develops from an increased intake of dietary iron alone; however, increased intake of iron supplements may lead to toxicity. Symptoms include fatigue, anorexia, dizziness, nausea, vomiting, headache, weight loss, shortness of breath, and possibly a grayish color to the skin.
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