It is easy to say iron. Women (always, almost all in the fight against iron), vegetarians and vegans know this very well, very well informed about bioavailability and assimilation of nutrients.
The iron contained in foods, both of animal and vegetable origin, it is not all always absorbed by our organism: there are many and complex biological mechanisms involved inassimilation of iron.
Let's try to understand a little better how to assimilate iron.
How iron is assimilated
Let's clarify first of all how much we need per day. The recommended daily doses (LARN) vary by age and sex; then general we say that for adults and postmenopausal women need 10 mg of iron per day, while for women of childbearing age they rise to 18 mg per day and 30 mg per day pregnant.
Where do we get the iron from? There are also several iron-rich foods of vegetable origin, not only of animal origin. The difference lies in the substances to which the iron is bound: iron-heme it is related to hemoglobin and constitutesand 40% of the iron in foods of animal origin, while iron does not heme It is in the 60% of the total iron in foods of animal origin and in foods of plant origin.
What's the difference? The heme iron is absorbed - directly with the entire associated heme group - more easily (about 20% of the iron present in food) from the human body; the absorption of non-eme iron (about 2-20% of the iron present in the food) which occurs after the detachment of the iron from the original molecule and the subsequent bond with sugars or acids, and is heavily influenced by the presence of other substances in the same meal (we will see them later, as "friends and enemies" of iron).
As you can see, the "equations" are complex and the assimilation of iron, even for foods of animal origin, is never complete.
To have a good assimilation of iron it is therefore essential know allies and "enemies".
How to promote the absorption of iron in the vegetarian diet
How to assimilate iron: the allies
The best ally to assimilate iron is the Vitamin C, which in addition to having significant beneficial virtues for the body, promotes the absorption of iron inside the cells: vitamin C increases the solubility of non-heme iron and makes its absorption in the intestine effective. Fructose and citric acid also have the same effect.
Some processes such as the leavening, sprouting and fermentation increase the absorption of iron.
Let us recall a few excellent sources of vitamin C, to be included in our meals to better assimilate iron: peppers, rocket, broccoli, cabbage, blueberry, strawberries, citrus fruits.
How to assimilate iron: the enemies
Especially for the non-heme form, iron assimilation is very sensitive to a number of factors and molecules. Here are some of them:
- I tannins present in some vegetables but especially in tea and coffee. THE tannins they bind to metals, in this case to iron, preventing its absorption and intestinal level. If you like them a lot, drink tea and / or coffee away from meals.
- Phytic acid (present mainly in radicchio, rocket, spinach), which sequesters the iron preventing its absorption.
- Oxalic acid (present mainly in spinach, beets, chard) and the polyphenols (present in tea, coffee, red wine and some spices) by binding to iron, they prevent its assimilation.
- Le fibers, which incorporate the iron molecules and transport them "towards the exit", preventing their assimilation. So pay attention to whole foods and leafy vegetables.
- Il football, as it acts in competition with iron, in the absorption mechanisms. Beware of milk and derivatives.
- - antacids, taken for gastric problems, decreasing acidity does not create the chemical environment suitable for assimilating iron.
Fundamental is the bowel health, the organ that physically carries out the absorption of iron. Intestinal diseases and celiac disease do not allow the correct assimilation of iron.
Iron, effects of deficiency and excess
To learn more:
> Foods rich in iron, what they are
> Iron and vitamin C