Foods richest in iron: heme, table, advice

Your ferritin level is too low? It’s necessary favor foods rich in “heme” iron, which are better absorbed by the body. List and advice with Laura Azenard, naturopath.

What foods contain heme iron?

Our diet provides two types of iron: heme iron (best absorbed) and non-heme iron.

► heme iron is contained in animal proteins such as red meats, fish and shellfishs (clams, oysters), offal (liver, kidney), charcuterie (black pudding)… The heme iron is relatively well assimilated during digestion : it is estimated that it is 25% bioavailable (the bioavailability of dietary iron corresponds to the percentage of dietary iron consumed that crosses the intestinal barrier). Namely that red meats or fish have a good zinc content, a trace element that contributes to the good assimilation of iron.

► the non-heme iron is contained in the fruits, vegetables and legumes. These products have a lower iron content and the latter is much less absorbable than heme iron: it is estimated that it is bioavailable up to 10%. Namely that among the foods containing non-heme iron, there are algae. These latter contain complexed iron, that is to say that this iron has the particularity of being surrounded by vegetable molecules allowing it to be much better assimilated by the body. The spirulina, wakame or dulse are algae that have a good content of complexed iron. But how to consume them? The spirulina can be found in food supplements, in powder or flakes that can be sprinkled on soups, salads, steamed vegetables or compotes. But beware, “spirulina is a real “sponge” and tends to soak up everything in the air or in the water with which it comes into contact, including pollutants. It is therefore better to choose it with the “Spiruliniers de France” logo, a label that respects organic commitments and a healthy growing environment.“, recommends the naturopath.

What is the list of iron-rich foods?

• spirulina (consume it in powder or flakes sprinkled on your salads, soups or green juices)
• black pudding (add it to your menus once a week)
• beef and duck meat
• offal: kidneys, liver
• dark chocolate (at least 70% cocoa)
• mussels and oysters
• lentils
• white beans
• whole grains: oatmeal, whole barley, oat bran, whole wheat
• dried aromatic herbs: thyme, basil, mint, marjoram, Provence herbs, parsley, savory, oregano…
• cumin seeds, fenugreek, fennel, coriander, chia, sesame…

Spinach ? According to Popeye, spinach is an incredible source of iron. However, with only 3mg per 100g, this vegetable is far from being the product that contains the most. However, cooked and boiled, spinach would contain more iron than raw. Plus, they’re powerful antioxidants and great sources of vitamin C.

Table of foods richest in iron

Below is the table of the richest foods that can easily be favored to increase your ferritin level. We do not voluntarily present the total list of foods according to their iron content because the quantities to be ingested to benefit from the benefits would be really very high (ex: dried thyme contains 124 mg of iron per 100 grams; dried basil 90 mg/100g or even dried mint 87.5 mg/100 g) or foods that are difficult to eat (raw liver, for example, richer in iron than cooked liver).

Handles (table of nutritional composition of Ciqual foods)

► The iron from plants is much better absorbed if it is combined with foods rich in vitamin C such as kiwis, red fruits, citrus fruits, guavas, peppers, fennel, spinach, cabbage… Ideally chosen as fresh as possible, seasonal, local and organic. “The idea is to combine legumes with vegetables rich in vitamin C : thus, we will not hesitate to prepare a pan-fried lentils with peppers for example!“, advises the naturopath.

► “Anything fermented will boost iron assimilation, like sauerkraut cabbage or sourdough bread which will also increase the digestibility of food“.

► Whole grains (whole wheat, brown rice) and legumes (beans, lentils) contain phytic acid in their shell, a biomolecule that prevents proper assimilation of nutrients. It is therefore advisable to soak whole grains and legumes (or sprout them) before cooking to remove phytic acid.

► You must beware of water that is too mineralized (such as Hépar or Contrex) which provide a surplus of minerals (zinc, magnesium, calcium…). These can slow down the assimilation of iron.

► The nutritional quality of all minerals is altered above 100°C, hence the interest of turn to gentle cooking (stewed, steamed, etc.) and at low temperature. Note that vitamin C is even more fragile since it deteriorates from 60°C.

Should we avoid tea and coffee when we lack iron?

It is actually necessary beware of the tannins present in tea, red wine or coffee which can alter the assimilation of iron of vegetable origin. It is considered better to drink a tea (ideally green or sencha, as these teas are oxidizing and rich in vitamin C) or a coffee between 30 minutes and 1 hour after the meal rather than at the same time.

Avoid iron overload!

Iron is an antioxidant when the body has a normal level. On the other hand, if it is in excess, it becomes very oxidative and can cause fatigue, a feeling of weakness and develop complications affecting the heart, liver and endocrine organs. “Beware of heme iron since, as our body assimilates it very well, some people – who overconsume red meat or processed meats – may experience iron overload and be at risk of developing low-grade inflammation (the intestine is damaged and becomes porous)“, specifies the expert. And if the body is overloaded with iron, there is more risk in the long term of developing a hemochromatosis (genetic disease linked to excessive iron absorption), or cardiovascular or respiratory disease, metabolic syndrome, or type 2 diabetes. Iron overload is relatively rare and can be treated if caught early. This problem concerns more certain men and women over the age of 50 who are less able to eliminate iron.

Thanks to Laura Azenard, naturopath.