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Blood, iron and iron deficiency - the unrecognized common disease

Iron deficiency is still a problem. About 10% of the German population suffers from iron deficiency.

What does this mean for those affected?

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Blood, iron and iron deficiency - the unrecognized common disease

Although it may sound strange at first glance, deficiency symptoms in the sense of nutrient deficiencies are still a problem in the 21st century.
One of the most important examples of this is iron deficiency. The German Society of Hematology and Oncology states the prevalence to be 5-10% of the population on average[1].
In Germany alone, that's over 8 million people, or in other words, the population of Munich, Hamburg, Berlin, Cologne and Düsseldorf combined. And we are talking about the average here.
Iron deficiency is a significant problem and can cause anemia, among other things. One would not suspect that a nutrient deficiency would be so pronounced here in Germany.
In pre-menopausal women, the prevalence of iron deficiency rises to as much as 20% and up to 8% of children suffer from this micronutrient deficiency. This does not include the number of unreported cases.

How does an iron deficiency develop, what problems does it cause and what does it have to do with our blood?

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Table of Contents

- The components of blood - where is the reference point to iron?
- Erythrocytes
- Hemoglobin
- How does the oxygen supply to our cells work?
- What happens when there is an iron deficiency?
- How does iron deficiency develop?
- Detect iron deficiency - our tips
- Treat iron deficiency - but how?
- Lactoferrin as a secret weapon
- This is our solution

The components of our blood - where is the reference point to iron?

Our blood can be divided into solid and liquid components.
The solid component, the blood cells, can be divided into red blood cells, white blood cells and platelets.
The liquid component is called blood plasma. This contains proteins (including antibodies and fibrinogen) and electrolytes. Fibrinogen is a precursor of fibrin, which is relevant for blood clotting. Antibodies are thus transported via the liquid component and ultimately detected in the laboratory. Furthermore, hormones, signal molecules, amino acids and glucose are transported to the target organ via the blood. Thus, our blood is the most important means of transport of the body.
White blood cells are part of the immune system, platelets are involved in wound healing and blood clotting, and red blood cells transport oxygen, among other things.

The best known are probably the red blood cells, also called erythrocytes. For our iron topic, they are also the most relevant of the three groups.


These "cells" have a simple structure. They no longer contain cell organelles, i.e. no mitochondria for energy synthesis and no cell nucleus with DNA. Therefore, they are not classified as true cells and are severely limited in what they can do. Their shape corresponds to a biconcave disk, since there is a trough in the center due to the lack of a nucleus.

Erythrocytes are also the reason for the red color of blood, as they contain the pigment hemoglobin and make up the largest proportion of blood, approximately 40%.

Their main function is to transport oxygen and carbon dioxide in the blood. Our cells need oxygen to enable metabolic processes to run efficiently. If our brain is not supplied with oxygen for just a few seconds, loss of consciousness occurs.
After a few minutes, irreversible damage and death of brain cells already occurs. Because erythrocytes make up the largest proportion of the solid components of the blood, they are also an important buffer system of the body, for example for the acid and base balance.

The protein hemoglobin, which is the main component of erythrocytes, is responsible for oxygen transport. There are approximately 280 million hemoglobin molecules in a blood cell.


The protein hemoglobin is composed of four smaller protein subunits, with a heme group attached to the center of each protein.
This heme group is the crucial part for binding the oxygen and carbon dioxide molecules.
In addition, the heme group contains the functionally important iron atom. Iron holds the heme group together and is also the site of oxygen binding. An iron atom of a heme group binds an oxygen or carbon dioxide molecule.
Thus, one hemoglobin binds four such molecules (at each protein subunit, one binds to the heme group present).

So we know: iron is an important component of hemoglobin. Iron is essential for the function of transporting oxygen to the tissues.

How does the oxygen supply to our cells work?

The transfer of oxygen to hemoglobin, to supply the body with oxygen, takes place in the lungs primarily at the alveoli (= smallest unit of the lung tree). When oxygen-rich air flows into the alveoli, oxygen can be released to the tissues via the blood-air barrier. Hemoglobin in the capillaries (= small blood vessels) binds the oxygen.
From here, the blood reaches the heart and is then distributed throughout the body. This oxygen-rich blood reaches the vicinity of the tissue, for example the muscle. The bound oxygen is released and carbon dioxide (CO2) is absorbed in return.

A good oxygen supply is important for one thing in particular: energy production in the target cell.

Energy is produced by cells largely in mitochondria. The energy carrier is then ATP, a substance with energy-rich compounds that can be split to release energy. Production requires a fair amount of oxygen, which, as we now know, can only get there with the help of red blood cells and the hemoglobin they contain. Energy is needed in the cell for almost every reaction. Whether muscle contraction, metabolism, protein synthesis, division, transport, or growth - ATP is always present.

What happens when there is an iron deficiency?

Iron deficiency has a significant effect on the function of erythrocytes. After about 120 days, erythrocytes are degraded. Therefore, there must be a constant replenishment. New erythrocytes are produced in the bone marrow, requiring a lot of iron to form hemoglobin. In fact, once completed, the erythrocyte can no longer produce proteins or divide because the cell organelles are removed.

Iron deficiency can result in either fewer erythrocytes being formed , or smaller erythrocytes. Thus, if there are fewer or smaller red blood cells circulating, the oxygen capacity automatically decreases along with them, since less hemoglobin is available due to the iron deficiency. In case of pronounced deficiencies, it can even lead to anemia (iron deficiency anemia).

There is a deficient supply, especially of the tissues of the extremities. Typical signs of insufficient blood supply are cold and blue hands or feet.
If a tissue is not sufficiently supplied with blood for a long time, this can lead to cell death.

How does iron deficiency develop?

Iron deficiency occurs in a large number of people, especially women.  Why? 

Menstruating individuals lose a considerable amount of iron every month due to period bleeding. The need is increased accordingly.
On average, a woman loses about 60 milliliters of blood per cycle, sometimes even more than 80 milliliters. 40% of this is red blood cells.
Women additionally have a higher risk of developing iron deficiency during and after pregnancy.

This is primarily due to 3 reasons:
- The growing fetus is completely supplied with iron and blood via the mother, as the corresponding organs are not yet fully formed
- During birth, the mother loses quite a lot of blood by shedding the placenta. Up to 500 milliliters are lost here
- During breastfeeding, the mother provides the child with many nutrients, including iron
Not only women are affected due to their biological basis. Iron deficiency can also occur due to poor nutrition.
Sources of iron are many seeds, kernels, legumes and meat. The content in meat depends on cooking and the type of meat. Chicken, for example, contains very little iron.
The dietary intake of iron in this case depends on the availability of iron. If it is bound to hemoglobin, which is the case with animal iron, it can enter the cell more easily. To enter the cell, it must be activated.
Iron deficiency is also a problem in infants. Within the first few weeks, the blood cells are exchanged in the infant's body. This can quickly lead to an iron deficiency if the mother's diet is inadequate.

How far do the causes of iron deficiency extend?
Is only food and menstruation or pregnancy responsible? In fact, more subtle factors play an enormous role.
These include hypochlorhydria (an under-acidified stomach) and SIBO (Small Intestinal Bacterial Overgrowth). In SIBO, there is bacterial overgrowth in the small intestine, or rather, a miscolonization of the small intestine.
This leads, among other things, to poor absorption of nutrients such as vitamin B12 and iron. SIBO is a common disease, but is often mistaken for irritable bowel syndrome. The under-acidified stomach is caused, among other things, by medication with acid blockers, by infections or by stress.

All these factors play a role in the development of iron deficiency. It is therefore not surprising that the occurrence of iron deficiency is not uncommon.

Detect iron deficiency - our tips

Determining iron deficiency can be difficult.

Various factors can affect the determination:
- Vitamin B12 deficiency may be the reason for reduced erythrocyte production
- Inflammation can greatly increase serum ferritin levels, which are usually quite informative, and mask iron deficiency
- Laboratory values vary in reliability: the serum iron value is hardly used any more because it is not meaningful
- Symptoms of iron deficiency are diffuse: fatigue and listlessness are symptoms of many deficiencies
- The threshold at which ferritin levels are considered to be of concern is 10 mg/dl; a large number of studies indicate inadequate supply even below 40 mg/dl [2].
Take good care that your doctor considers these points and intervenes already at a value below 40 mg/dl - so further damage can be prevented.

The issue of symptoms is also important. Since, as is actually always the case, symptoms of nutrient deficiencies are diffuse, you should pay particularly close attention to warning signals.

These can be:
- Fatigue
- Sleep problems
- Lack of energy
- Cold extremities (and red/blue hands)
- Endurance problems/lack of performance (this is especially true for athletes).
- Headache
- Dizziness
- Forgetfulness
- Concentration disorders
- Pale skin
- Shortness of breath
- Increased susceptibility to infections
- Hair loss, brittle nails

Treat iron deficiency - but how?

Whether prophylactically or when iron levels are too low, the logical answer is: iron supplementation. It sounds simple, but unfortunately one or the other obstacle gets in the way.
First you should think about the type of preparation. There are many different administration forms of iron. One can:

- Supplement active iron however, 30-50% of individuals experience discomfort due to the reactivity of the iron (ferrous sulfate).
- Supplement herbal inactive iron unfortunately, this must first be activated (iron extract, e.g., from curry leaf).
- Take chelated forms of iron chelated means amino acids are bound to iron (iron bisglycinate).

We opted for the last variant. Iron bisglycinate has the advantage that it is less reactive and therefore more tolerable. It can also be better absorbed because internally active iron is bound. With chelated forms, smaller amounts of iron are also usually sufficient to replenish stores, since less loss is expected in the stomach and small intestine.
This brings us to the next point: the dose.
Preparations with a dose of 10-100 mg can be found on the market. Very high doses are not toxic, but cause nausea, stomach discomfort and other symptoms in some people. A moderate dose with an effective iron compound seems more reasonable to us.

Let's get to the most exciting part. The basics are covered, but there are still a few details that can help you absorb and utilize iron better:
- Vitamin C is known to increase the absorption of iron as it can activate iron
- B vitamins, especially B6, B9 and B12, are relevant in the utilization of iron; vitamins B9 and B12 are involved with iron in blood formation
- Copper deficiency may hinder iron transport; adequate copper supply should be ensured
- Lactoferrin can optimize iron utilization

Lactoferrin as a secret weapon

Lactoferrin is a protein that some people may have heard of in the context of breast milk.
This protein belongs to the transferrin family, which means that it is responsible for iron transport, among other things. But lactoferrin is much more than an "iron cab".
It can bind and transport iron and even fight microorganisms. Lactoferrin acts as an antimicrobial peptide, it can fight bacteria [4]. It thus protects the infant against infections after birth.
Adults also benefit, as it is found, for example, in certain immune cells that circulate in the blood [5].

Returning to iron transport, if lactoferrin is saturated with iron before it is absorbed with food or supplements (as is the case in breast milk), it enters the intestine in this form and is absorbed intact. This achieves several goals at the same time:

- Almost 100% of the iron is absorbed and supplied to the metabolism (conventional oral iron has an absorption rate of 10-15%).
- The iron does not have to be activated, the process is thus independent of gastric acid.
- The iron is not present in free form, so it cannot become reactive (like supplied, active iron) and cause complaints.
- The iron cannot be absorbed by bacteria, "feeding" a SIBO (which was a bacterial growth in the small intestine) is thus excluded.
- The lactoferrin can have an antibacterial effect, a possible existing imbalance of bacterial strains in the small intestine is thus rather reduced than supported.


[1]: HEALTHCARE-IN-EUROPE (2021) ‚Iron deficiency and anaemia‘, [Online].  Available:

[2]: BREYMANN, C., RÖMER, T. & DUDENHAUSEN, J. W. 2013. Treatment of Iron Deficiency in Women. Geburtshilfe und Frauenheilkunde, 73, 256-261.

[3]: HAO, L., SHAN, Q., WEI, J., MA, F., & SUN, P. 2019. Lactoferrin: Major Physiological Functions and Applications. Current protein & peptide science, 20(2), 139–144.­180514150921

[4]: YEN, C.-C., SHEN, C.-J., HSU, W.-H., CHANG, Y.-H., LIN, H.-T., CHEN, H.-L. & CHEN, C.-M. 2011. Lactoferrin: an iron-binding antimicrobial protein against Escherichia coli infection. BioMetals, 24, 585-594.

[5]: VAN DER STRATE, B. W., BELJAARS, L., MOLEMA, G., HARMSEN, M. C., & MEIJER, D. K. 2001. Antiviral activities of lactoferrin. Antiviral research, 52(3), 225–239.