Why do we need iron?
• Iron is involved in the electron transport system. This system controls the release of energy from cells.
• Iron is required for red blood cell production.
• Iron is required for a healthy immune system
• Iron is responsible for transportation of oxygen throughout the body.
In human bodies, iron is what helps transport oxygen to other parts of the body. High iron content in the body results in cell growth and differentiation. Most iron (70 to 95 percent) in our bodies is present in hemoglobin. Hemoglobin is the oxygen-carrying pigment and predominant protein in red blood cells. Iron is also found in myoglobin - an iron-containing protein found in muscle fibers that transports oxygen within muscles and acts as an emergency oxygen storage for the rest of the body. Iron also makes up part of many proteins and enzymes in the body.
Iron deficiency is the most common nutritional deficiency worldwide. Although full-blown anemia is rarely evident, partial deficiency is widespread. Women are more prone to iron deficiency than men. Iron consumption may be enough, but iron absorption may not be. The first symptom of iron deficiency is tiredness. The rest are extreme fatigue and feeling of weakness, lack of stamina, headaches, insomnia, breathlessness, loss of appetite, pallor, brittle hair, hair loss, irritability, smooth/reddened/sore tongue, thin/brittle/white finger nails, low blood pressure when changing position from sitting to standing up, pica (the development of an appetite for unusual substances such as paper or clay products) and pacophagia (the development of an appetite for ice).
Our iron absorption depends on the form of the iron. The iron from animal sources, known as heme iron, is absorbed easily by the body. The iron found in vegetable sources, known as non-heme iron, is less available to the body. The amount of iron absorbed from vegetarian foods is around 1 - 10% , while it is 10 - 20% from animal foods.
The following factors will increase the iron absorption from non-heme foods:
• A good source of vitamin C (ascorbic acid) - i.e., oranges, grapefruits, tomatoes, broccoli, and strawberries, eaten with a NON-HEME food
• A HEME and NON-HEME food eaten together
• A NON-HEME food cooked in an iron pot, such as a cast iron skillet
The following factors will decrease non-heme iron absorption:
• Large amounts of tea or coffee consumed with a meal (the polyphenols bind the iron).
• Excess consumption of high fiber foods or bran supplements (the phytates in such foods inhibit absorption).
• High intake of calcium - take your calcium supplement at a different time from your iron supplement.
The Recommended Dietary Allowance (RDA) for iron for non-vegetarian pre-menopausal women is 18 mg/day. The RDA for non-vegetarian men and post-menopausal women is 8 mg/day. Because of iron absorption issues in a healthful, high-fiber vegetarian diet, the RDAs for vegetarians are higher - 14 mg/day for vegetarian men and 33 mg/day for vegetarian women. The upper level of intake should not exceed 45mg/day.
Top Ten Iron-Rich Foods
• clams, cooked, 3 oz (23.8 mg)
• tofu, 1/2 cup firm (13.2 mg)
• raisin bran, ready-to-eat, 3/4 cup (4.5 mg)
• sirloin steak, cooked, 3 oz (2.9 mg)
• shrimp, cooked, 3 oz (2.6 mg)
• black beans, boiled, 1/2 cup (1.8 mg)
• chickpeas, canned, 1/2 cup (1.6 mg)
• turkey breast, 3 oz (0.9 mg)
• bread, whole wheat, 1 slice (0.9 mg)
• chicken breast, skinless, 1/2 breast (0.9 mg)
**** Spinach is NOT a good source of iron. Spinach contains about as much iron as any green vegetable, but it also contains oxalic acid which blocks about 90% of the iron from being absorbed.
Iron-Rich Foods
| Food | Serving Size | Iron Content (mg) |
|---|---|---|
| Cereal, ready to eat, fortified | 1 cup | 1 to 16 |
| Clams, canned | 1/4 cup | 11.2 |
| Beef liver, fried | 3 oz | 5.3 |
| Braunschweiger | 2 oz | 5.3 |
| Molasses, blackstrap | 1 tablespoon | 5.0 |
| Baked Beans | 1 cup | 5.0 |
| Oysters, cooked | 1 oz | 3.8 |
| Baked potato, with skin | 1 | 2.8 |
| Soup, lentil and ham | 1 cup | 2.6 |
| Burrito, bean | 1 | 2.5 |
| Soup, beef noodle | 1 cup | 2.4 |
| Rice, white, enriched | 1 cup | 2.3 |
| Ground beef, lean | 3 oz | 1.8 |
| Apricots, dried halves | 10 | 1.7 |
| Bread, whole wheat | 1 slice | 1.2 |
| Broccoli, fresh cooked | 1/2 cup | 0.7 |
| Egg | 1 | 0.7 |
Also, Vitamin C enhances iron absorption from plant sources, so it is a good idea to drink orange juice with iron-rich foods. Keep in mind that drinking tea with meals can act as an iron blocker. Other iron blockers include carbonates, oxalates, and phosphates. Foods that contain these iron blockers include cranberries, rhubarb, spinach, and soda.
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