Iron is an essential mineral that the body needs for growing and developing. Our organism contains more or less 3-4 g of iron and 65% can be found in hemoglobin and 10 % in myoglobin. Hemoglobin is a protein carrying oxygen across all parts of the body, and myoglobin, a protein that provides oxygen specifically to muscles. The rest of the iron presents in our body has either function of deposit, and it can be found in liver, bone marrow or spleen, or enzyme. Normally, an adequate diet compensates for the physiological elimination of iron and the quantity is kept in balance, thanks to the reserves and the body self-regulation of absorption and elimination. But it can happen, for different reasons, that we break this balance and we either have excess or deficit of iron. Today we keep focusing on Iron deficit.
Foods rich in iron are: offals (especially liver), meats (red and white), fish, mollusks and crustaceans, egg yolk, legumes (e.g. lentils, beans, chickpeas, peas, black-eyed peas, soybeans, etc.) and derivatives such as tofu, dried fruit and green leafy vegetables (such as watercress, spinach), black molasses (derived from cane sugar).
Let´s go into chemistry. Iron can be found in two different forms: heme and non-heme iron.
Heme form is usually found in animal origin products and easily absorbed by our body. Non-heme iron can be found mainly in vegetal origin products and it has a slower and more difficult absorption process.
The presence of certain substances, namely phytates, oxalates and phosphates contained in plants, which together with iron form insoluble complexes, reduces the bioavailability of iron. Instead, vitamin C can accelerate the absorption.
In vegetable products, the iron content decreases by about 15% for cooking in poaching and by about 10% for steaming.
The daily intake of iron depends mostly on our age, gender and, for women, also if there is a pregnancy, lactation, or postmenopausal status.
As an indication, I will only refer to the population reference intake provided by EFSA (European Food Safety Authority) which is relevant for at least 98% of the healthy population in each specific group)
LARN / SINU ITALY: https://sinu.it/2019/07/09/minerali-assunzione-raccomandata-per-la-popolazione-pri-e-assunzione-adeguataai/
Iron supplementation is necessary when there is a clear deficit of iron in our body. The deficit might be caused by different situations.
Here I will mention the most common ones:
-reduced intake, due to restricting diets;
-diet rich in bran (used usually to regulate intestinal function) or tannin, phytates, oxalates and phosphates;
-insufficient absorption due to different reasons: gastrointestinal disorders, abuse of laxatives, diarrhea etc.
-excessive bleeding (hemorrhoids, nosebleed, heavy menstrual flow, ulcers, gastrointestinal bleeding, etc.);
-pregnancy and breast feeding;
-sports (especially endurance running).
We can identify if we are in deficit of iron by regularly analyzing our blood.
Some signals of deficits are: weakness, fatigue, shortness of breath, irregular heartbeat, sensitivity to cold and cooling, pale skin and mucous membranes (inside of the mouth, eyelids), restless legs syndrome, formation of ulcers on the tongue, spoon-shaped nails (concave in the center), headache, dizziness, drowsiness, swelling of the spleen.
Iron deficit can be caused by either physical activity or restricting diet.
Regarding physical activity, mainly after a prolonged running races such as the marathon, in more than 80% of the subjects, gastrointestinal bleeding phenomena are detected. It is hypothesized that this phenomenon is linked to the numerous traumas suffered by the intestinal walls during the running action and to the lower blood supply to the intestine. Although modest, this bleeding causes iron losses between 0.7 and 0.9 mg. Furthermore, the small urinary losses of iron in the sedentary subject (0.1mg / day) can increase considerably in athletes.
A special consideration must be done for women. The amount of blood that a woman loses each month with menstruation is between 30 and 60ml of blood. A woman who loses 60 ml of blood per cycle loses on average 1.0 mg of iron per day, which is 30 mg of iron per month. To these physiological losses in the female athlete must be added urinary and gastrointestinal losses and possibly dietary restrictions that can decrease the iron intake with the diet.
Moving to nutrition, also in case of prolonged time following a diet not providing sufficient iron and/ or excessive quantity of phytates, oxalates and phosphates, it can lead to iron deficit.
If we prolong the deficit of iron for too long, we risk becoming anemic. Anemia is a condition where there are less blood cells circulating in our vessels. This causes reduction in the amount of oxygen carried through the rest of the body which leads to the symptoms I mentioned previously.
Vegan people can cover the recommended iron daily intake. Here my tips how to guarantee a proper intake of iron:
· soaking cereals and legumes before cooking;
· combining foods rich in non-heme iron at every meal with foods containing vitamin C such as citrus fruits, cabbage, peppers, rocket and lettuce;
· do not combine foods rich in iron with coffee, tea, tannins, oxalates to avoid slowing down iron absorption;
· Regularly check blood parameters to make sure iron is good enough and eventually supplement in case of deficit.
Unmilk plant-based drinks offer a good source of iron: if we take as example the Schoko Hafer Drink, which is by the way my favorite, we can see that it provides 5,6 mg Iron in 330 ml which is 35% the daily reference intake of a woman over 18 years old in pre-menopausal stage. So it is a great support to make sure we have a proper daily intake of Iron. You can shop Unmilk here using my code VALENTINA10: 10% discount on every products.
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