- Iron is a mineral necessary to the body.
- It participates in tissue oxygenation.
- It also plays a role in DNA synthesis.
- 70% is found in hemoglobin.
- Meat products are the best source of this mineral.
- Vitamin C promotes iron absorption.
Why should we
eat some daily?
The body cannot synthesize iron. That means it must be obtained daily from food sources. Nature is well designed: the iron absorption rate varies according to the state of the body’s mineral reserves (ferritin). This defense system makes it possible to avoid the toxic effects of an excess of this mineral and also to fight against deficiency, particularly common among women.
In 2011, the World Health Organization estimated that around 29% of women of childbearing age were anemic, a percentage that would be even higher among pregnant women. Half of these cases were thought to be due to iron deficiency (anemia).
The hemoglobin present in the red blood cells contains 70% of the body’s iron. Iron makes it possible to capture oxygen, which is then transported to the cells. The mineral is also present in the myoglobin in muscles, making it possible to stock oxygen.
Nonheme iron (which is not present in hemoglobin) participates in numerous metabolic reactions. That means that this mineral is vital for energy production, normal function of the immune system, and cognitive development in children.
What is the
Meat, meat products, and fish are the best dietary sources of this mineral. Iron, more specifically heme iron, is available in large quantities in those foods. Heme iron is (around five times) better absorbed than the nonheme iron found in vegetables and dairy products. Heme and nonheme iron are absorbed differently in part because of certain compounds present in plants (phytic acid, oxalic acid, and tannins) and because of the calcium in milk.
However, two simple tricks can improve absorption of this mineral found in plants:
|Iron content in foods||mg/100 g|
|Cooked blood sausage||22|
|Roasted pigeon meat||20|
|Lamb liver, clams||14|
|Powdered cacao, stewed rabbit, poultry livers||10-12|
|Cooked kidneys, soy flour, dry lentils||8-9|
|Mussels, wheat germ, dry white beans, toasted pistachios||7-8|
|Foie gras, sunflower seeds, oysters, veal liver, enriched cornflakes, country-style pâté, fresh parsley, roasted chervil, wheat, dried apricots, cashews, Müesli cereal||5-6|
|Almonds, oat flakes, whelks, horsemeat, hazelnuts, roast beef, whole-wheat flour, stewed beef, cooked shrimp, spinach, cooked lentils, dandelion greens, steak, dried dates||3-4|
Myths about iron
The best-known myth goes back to Popeye, the famous sailor from an American comic strip whose superhuman force came from canned spinach, a vegetable lauded at the time (in the 1920s) for its high iron content. In reality, spinach is indeed a source of iron. However, this iron is less easily absorbed than iron found in meat. Maybe Popeye would have been even stronger had he eaten a balanced meal!
What are its particularities?
Though iron deficiency is widespread throughout the world, supplements should ideally be taken only under medical supervision, because the human body has few ways of eliminating this trace element and it therefore builds up quickly. In other words, it is better to reach the daily intake through your diet.
If you are vegetarian, remember the “lemon trick”, with plant foods rich in vitamin C, such as citrus fruit, cabbage, and bell peppers.
What if I eat
too much or too little?
As mentioned previously, advanced iron deficiency can cause anemia, the sign of a lower hemoglobin concentration in the blood. The main symptoms, when they appear, include fatigue, pallor, and more pronounced shortness of breath during physical effort.
The consequences of a more moderate deficiency are still poorly defined. Such a deficiency may cause reduced capacity for physical effort, reduced intellectual performance, lowered resistance to infections, problems during pregnancy, etc.
An excess can also be harmful. Epidemiological data indicate a link between high iron intake and increased incidence of cardiovascular diseases, type II diabetes, and some cancers of the digestive system. However, the risk seems to be fairly low.