- Why is iron so important?
- Causes of iron deficiency
- Chronic blood loss through the period
- Iron deficiency in chronic inflammatory bowel disease
- Inadequate dietary iron intake
- Daily iron requirements for women
- Iron is not just iron
- How are iron deficiency and iron deficiency anemia diagnosed?
- Proper diet for iron deficiency
Iron is one of the trace elements because the body only needs it in very low concentrations. Nevertheless, there are 2.5 - 4.5 grams of the heavy metal in the body of a healthy adult. For comparison: a 20 cent coin weighs 5.7 grams and is therefore only slightly heavier than the iron stores in your body.
Iron deficiency is a global health problem and the most common deficiency symptom. It is assumed that up to two billion people suffer from an iron deficiency, in Germany it is 8% of the population. Women of childbearing age are disproportionately affected: every fifth woman in Germany suffers from an undersupply of the important trace element.
So it's no wonder that millions of women are looking online for the best iron deficiency foods. The phrase “best foods for iron?” provides over 3 million results on Google.The search result is surprising, however.Because the search engine only names vegetable sources of iron, it does not include the actually best foods with the highest iron content, such as duck liver or black pudding.
There is enough iron in duck, pork, and beef liver to easily make it to the top of the list. In addition, the trace element from animal sources is absorbed much better by the body than iron from plant sources.
In contrast to Google and Co., we want to shed more light on the topic of iron deficiency without hiding facts in order to serve a political agenda. Even if the trend towards a meat-free diet cannot be slowed down, we think that your own health has priority. In the following, Carnivoro explains the task of iron in our body, causes and symptoms of iron deficiency and which foods are particularly suitable for preventing it.
Why is iron so important?
Iron is a vital trace element and an important component of the red blood pigment hemoglobin. This iron-rich protein complex forms 90% of our red blood cells and gives them their typical red color. Since oxygen and carbon dioxide are only sparingly soluble in water, hemoglobin binds the oxygen in the lungs and transports it to the cells in the tissue via the bloodstream. There, carbon dioxide is absorbed and travels through the red blood cells back to the lungs, where CO2 is exhaled. Since red blood cells have an average lifespan of 100 days, our body must constantly regenerate blood with the help of iron. If the heavy metal is missing, the oxygen transport is restricted.
Iron also plays a key role in energy metabolism. Because our cells need the trace element to produce ATP (our body's main energy supplier) in the mitochondria. You may still remember the respiratory chain from biology class with horror. Without iron, these complex reactions to generate energy cannot take place. If the iron store is not sufficiently filled, the ATP production suffers. The body has less energy available. Tiredness, exhaustion and exhaustion can be the result.
The immune system also needs iron to function properly. Immune cells can only be produced and activated if there is enough iron in the body. Iron deficiency weakens the immune system and makes the body more susceptible to infections. A research team from the German Cancer Institute in Heidelberg was able to show in experiments with mice that iron deficiency also inhibits the production of so-called neutrophilic granulocytes, which make up almost two-thirds of our white blood cells.
An adequate supply of iron to the embryo is vital even in the womb. Because iron plays a key role in brain maturation. Our brain needs the trace element for optimal development. Especially in the first 3 years of life, iron deficiency anemia can impair the acquisition of cognitive abilities. But iron deficiency can also limit mental performance in adulthood. If our brain does not get enough iron, it often leads to poor concentration or forgetfulness.
Causes of iron deficiency
Iron deficiency is when more iron is consumed than the body absorbs over a long period of time. The iron stores in the body have to be tapped into because there is not enough replenishment from food. Although the body's iron stores are not completely full when there is an iron deficiency, the HB value (hemoglobin content of the red blood cells) remains normal. Only a look at the ferritin value reveals how the iron stores are doing.
Chronic blood loss through the period
In Germany, chronic blood loss is the most common reason for iron deficiency. Iron deficiency anemia is only spoken of when the hemoglobin concentration in the blood falls below the gender or age-specific guideline. In young women, this drop is mainly due to the monthly period. 15% of all women tend to have heavy menstrual bleeding and are therefore particularly at risk. Myomas, i.e. growths in the uterus, and tumors can also lead to blood loss. Rarer is the excretion of hemoglobin through the urine due to hemolysis (breakdown of the blood) as a symptom of infectious diseases such as malaria or yellow fever.
Iron deficiency in chronic inflammatory bowel disease
In postmenopausal women, bleeding in the gastrointestinal tract is the main cause of iron deficiency. People with chronic inflammatory bowel diseases (IBD) such as Crohn's disease or ulcerative colitis are particularly often affected: it is estimated that 60-80% of all IBD patients suffer from iron deficiency, up to 50% suffer from anemia . The proportion is likely to be even higher in women with IBD. But gastrointestinal ulcers, inflammation of the gastric mucosa or hemorrhoids can also lead to ongoing blood loss.
Inadequate dietary iron intake
Iron deficiency can also be caused by one-sided meatless eating habits. Vegans and vegetarians, small children, people with eating disorders or severe alcohol addiction are particularly at risk. The mixed consumption of foods that are particularly rich in iron with coffee, tea, red wine, dairy products, cola or spinach should also be avoided, since the iron robbers they contain inhibit the absorption of the trace element. Caffeine, tannins, calcium salts, foods containing phosphate and oxalic acid should be avoided if you already have an iron deficiency.
Daily iron requirements for women
According to the German Society for Nutrition (DGE), women of childbearing age should take in 15 mg of iron through food, and pregnant women a whole 30 mg. If breastfeeding, the daily iron requirement is 20 mg. Women with regular menstrual periods lose up to 3 mg of iron per day, after menopause it is about 1 mg per day.
Excess iron is stored in the liver and spleen and bound to the protein ferritin. If not enough iron is supplied through food or dietary supplements, the iron requirement must be covered by the iron stores.
Particularly in the case of women, who disproportionately frequently do without meat, the daily loss of iron often cannot be compensated for through diet. Because even if meatless iron suppliers such as legumes or oatmeal are rich in iron, iron from plant sources is only poorly absorbed by the body.
Iron is not just iron
How easily iron can be absorbed by the body depends on the oxidation state of the heavy metal. Divalent iron (Fe2+) is mainly found in animal foods such as meat, fish, offal and poultry and is also known as heme iron. It has a bioavailability of 15-35%. This means that on average a quarter of animal iron can be absorbed by our small intestine. The absorption rate of the trivalent iron (Fe3+, also called non-heme iron) found in plants is 3-8%.
When it comes to the actual absorption of iron by our body, no plant-based food can hold a candle to the liver. Even if oat flakes, legumes and leafy vegetables regularly feature in the best lists of health blogs and women's magazines, most plant-based iron sources only play in the second league due to their significantly poorer bioavailability.
How are iron deficiency and iron deficiency anemia diagnosed?
Iron deficiency is not the same as iron deficiency. If too little iron is taken in through food over a long period of time to compensate for the daily iron loss, the first signs of iron deficiency appear. How advanced an iron deficiency is can only be clarified by going to the doctor. A blood test provides information
- Hemoglobin content of red blood cells (Hb value)
- Level of iron stores (serum ferritin value)
- Iron saturation of the iron transport proteins in the blood serum (transferrin saturation)
If the Hb value and transferrin saturation are in the normal range with a low serum ferritin value (<30 µg/l), this is referred to as a latent iron deficiency . Since the storage iron has been opened, but the body's iron requirements can still be covered by the iron stores, the latent iron deficiency often goes unnoticed at first or is accompanied by unspecific symptoms such as tiredness, irritability, difficulty concentrating, headaches or susceptibility to infections. Latent iron deficiency does not yet mean anemia.
With prolonged iron deficiency, the iron stores are depleted, so there is not enough iron available for the formation of new red blood cells. Due to the lack of iron, the hemoglobin content of the red blood cells decreases. The Hb value falls below the normal value for women of 12-16 g/dl. The blood count shows that the number and size of the red blood cells decreases due to the blood pigment deficiency. A decrease in the transferrin saturation in the blood serum shows that less transport proteins are loaded with iron. Only now can one speak of iron deficiency anemia (also manifest iron deficiency).
The unspecific signs of latent iron deficiency are then joined by symptoms such as brittle nails, sore tongue or corners of the mouth, ringing in the ears, hair loss or difficulty swallowing. If there is a suspicion of iron deficiency or iron deficiency anemia, this should be clarified promptly by a blood test with the family doctor.
Proper diet for iron deficiency
Since women have an increased risk of iron deficiency due to periods and pregnancy, an iron-rich diet is particularly important to prevent iron deficiency.
What to eat if you are iron deficient
Wheat bran (16mg/100g), pumpkin seeds (12.5mg/100g) or soybeans (9mg/100g) regularly top lists of the foods richest in iron. It is not mentioned that duck liver contains 30mg/100g almost twice as much iron as the best plant-based alternative. Pork and calf's liver also contain substantial amounts of the vital trace element. If you also take into account the poor bioavailability of non-heme iron sources, then no plant-based food would make the top 10.
Assuming an average bioavailability of 5%, you would need to eat 125g of wheat bran for your small intestine to absorb 1mg of iron. In order to cover about 50% of your daily iron requirement with the best plant-based source of iron, you would have to eat a whole kilogram of wheat bran.
If you like the taste of duck liver, then 130g is enough to cover half of the recommended daily dose. If you don't like the taste of liver, it's better to use freeze-dried beef liver capsules. These are odorless and tasteless and are ideal as an additional source of iron with meals.
How much iron is supplied to the body therefore only plays a subordinate role. What matters is how much iron the body can actually absorb.
Iron content per 100g in mg |
Iron absorption* per 100g in mg |
|
duck liver |
30.5 |
6.1 |
blood sausage |
29 |
5.8 |
pork liver |
18 |
3.6 |
calf liver |
9 |
1.8 |
beef liver |
7.8 |
1.6 |
Liverwurst |
7 |
1.4 |
beef |
3.3 |
0.8 |
wheat bran |
16 |
0.8 |
pumpkin seeds |
12.5 |
0.6 |
soybeans |
9 |
0.5 |
* Estimated iron absorption taking into account the differences in bioavailability between Fe2+ and Fe3+
In contrast to other online publications, however, we do not want to hide the fact that vitamin C can increase the iron absorption of non-heme iron. Small amounts of vitamin C are often sufficient to improve iron absorption from plant sources.
Unfortunately, many plant-based foods contain antinutrients that can inhibit the absorption of the trace element when mixed with foods containing iron. Tannins, phytic acid, oxalic acid and phosphates, which are mainly found in coffee, black tea, red wine, cola, spinach, dark chocolate and grain products, are particularly problematic. The calcium contained in dairy products can also reduce the absorption of iron. In contrast, the absorption of heme iron is hardly influenced by antinutrients.
Better safe than sorry
Even if iron deficiency is a rather rare deficiency symptom in our latitudes, women are disproportionately affected by iron deficiency. This often develops gradually, so that a latent iron deficiency goes unnoticed for a long time. The visit to the doctor often only occurs when the iron stores are already exhausted. Due to the unbroken trend towards a meat-free diet, more and more women are doing without the best sources of iron, such as liver and red meat. We hope that our article will help you to identify iron deficiency at an early stage or to prevent it with an appropriate diet.
DISCLAIMER:
This article for information only. The text does not claim to be complete, nor can the topicality, correctness and balance of the information provided be guaranteed. The text in no way replaces the professional advice of a doctor or pharmacist and it must not be used as a basis for independent diagnosis and starting, changing or stopping treatment of diseases. If you have health questions or complaints, always consult your trusted doctor!