Iron Deficiency - Everything You Need to Know Part 2

CAUSES OF IRON DEFICIENCY

Before you start supplementing iron, it is worth considering what is primarily responsible for your iron deficiency.

Finding this cause and eliminating it (if possible) is crucial to rebuilding its deficiencies with supplementation, and then preventing recurrence of deficiencies with optimal nutrition.

The causes of iron deficiency can be divided into:

1. Inadequate dietary intake of products rich in heme iron, a diet rich in phytates, oxalates, calcium or phosphates that hinder iron absorption, a poorly composed vegan and vegetarian diet;

2. Increased body needs combined with inadequate dietary intake (pregnancy, breastfeeding, growing children, athletes);

3. Reduced absorption

The presence of sufficient stomach acid is essential for proper iron absorption, therefore people who have had bariatric surgery or gastrectomy are susceptible to iron deficiency due to reduced absorptive surface area and reduced gastric acid secretion.

Iron absorption is impaired by long-term use of PPIs, the presence of Helicobacter pylori, parasitic infections, and autoimmune gastritis.

The overuse of nonsteroidal anti-inflammatory drugs also impairs iron absorption.

Dietary factors that interfere with iron absorption include: consuming coffee, tea, calcium (in supplements or dairy products), cocoa, products rich in oxalates or phytic acid around iron-rich meals or iron supplementation.

4. Chronic inflammation – anything that increases hepcidin levels and thus reduces iron absorption. More on hepcidin later in this article.

5. Blood loss (internal bleeding, excessively heavy and long periods in women, too frequent blood donation in blood donors, accidents, injuries, etc.)

6. Genetic factors.
   

   A FEW WORDS ABOUT HEPCIDIN

Due to the fact that Both iron deficiency and excess are harmful, our body has precise mechanisms for regulating iron metabolism.

Hepcidin is a hepatic peptide hormone that controls iron homeostasis in the body as it is the primary regulator of intestinal iron absorption.

The concentration of hepcidin is variable and depends primarily on the state of systemic iron metabolism and ferritin level, but its level is also influenced by other factors independent of systemic iron stores, such as hypoxia or the presence of inflammation.

In response to increasing iron stores, the liver produces hepcidin, which inhibits intestinal absorption and prevents further excess accumulation. In iron deficiency anemia, hepcidin levels are undetectable or very low to allow for optimal iron absorption.

In summary, an increase in hepcidin inhibits iron absorption, a decrease in hepcidin increases iron absorption.

It is worth knowing what else influences the regulation of hepcidin production, as this knowledge answers the question why some people find it so difficult to correct iron deficiency, despite proper eating habits or iron supplementation.

1. High hepcidin concentration is observed in clinical conditions associated with an inflammatory reaction, such as: anemia of chronic disease (ACD), rheumatoid arthritis, inflammatory bowel diseases, colon cancer, injuries, chronic kidney disease, sepsis.

Interleukin 6 (IL-6), a major proinflammatory cytokine, is responsible for increased hepcidin synthesis. All conditions that cause increased IL-6 levels can impair intestinal iron absorption by increasing hepcidin levels. This also applies to parasitic infections and other conditions that further enhance IL-6 production, such as: excess weight, chronic stress, insufficient sleep (either quantity or quality), overeating, smoking, excessive alcohol consumption, excessive training (more than two hours of intense exercise per day), as well as a lack of recreational activity and a sedentary lifestyle.

2. Genetic issue.

The TMPRSS6 gene encodes matriptase-2. Matriptase-2 is an enzyme that increases iron absorption by regulating hepcidin production.

Changes in this gene probably cause excessive stimulation of hepcidin synthesis – this condition is called iron-refractory iron deficiency anemia (IRIDA).

OPTIMAL NUTRITION IN THE PREVENTION OF IRON DEFICIENCY

Under normal circumstances, if we do not completely eliminate meat and fish from our diet, we eat quite a variety of foods and we do not have any other reasons mentioned above that may disturb the absorption of iron, there is no need to be particularly careful about the appropriate composition of meals.

However, if we have a tendency to constantly recurring iron deficiency anemia or there is still a latent iron deficiency (low ferritin), I would like to remind you that it is worth looking for why this is happening and addressing the main cause, then correcting the deficiencies with iron supplementation, and then taking a closer look at the nutritional aspects in order to maintain the appropriate iron reserves in the body after the intervention.

The pH-dependent process of iron absorption in the duodenum is inhibited or enhanced by certain nutrients.

There are two main types of iron we obtain from our diets – non-heme iron and heme iron. Heme iron, derived from hemoglobin and myoglobin of animal origin (red meat, offal, poultry, fish), is the most easily absorbed form of iron. Non-heme iron, on the other hand, is a plant source of iron (found in cereals, legumes, nuts, seeds, and some vegetables).

The body can absorb approximately 15-35% of the heme iron present in meals. Relatively few dietary factors negatively affect the absorption of heme iron.

Most dietary iron comes from non-heme iron. The paradox is that plant sources typically contain more iron per 100 g than animal sources, but at the same time, plant sources rich in non-heme iron contain components that limit its absorption. Only 2–20% of non-heme iron is absorbed by the body, depending on the presence of various factors, either inhibiting or enhancing its absorption. Many factors influence the absorption rate of non-heme iron compared to heme iron.

The absorption of non-heme iron is inhibited by:

• phytic acid (found in whole grain bread, cereals, legumes, nuts and seeds);

• oxalic acid (found in, among others, spinach, rhubarb, cocoa and chocolate, sorrel, nuts, coffee and tea);

• polyphenols (found in tea, coffee, fruits, vegetables, some cereals and legumes);

• some proteins (e.g. soy protein, egg whites, casein, whey);

• Calcium interferes with the absorption of both heme and non-heme iron.

The effect of inhibitors on iron absorption is greatest when they are consumed with meals containing iron sources.

A few basic rules on how to ensure better iron absorption:

1. Seeds, groats, and legumes should be soaked, cooked, sprouted, and fermented to remove iron-binding phytates.

2. In vegetables such as spinach, the amount of oxalic acid can be reduced by as much as about 50% after cooking, which can increase the bioavailability of iron.

3. If we want to ensure good iron absorption from a particular meal, we should not add dairy products, calcium-fortified drinks or, especially, calcium supplements to it.

4. Do not drink coffee or tea with meals, which can reduce iron absorption by up to 90%.

5. Add sources of vitamin C to your meals, as scientific research shows that it can counteract the effects of all dietary iron absorption inhibitors when incorporated into a diet with high non-heme iron availability. Vegetables rich in vitamin C include parsley, bell peppers, Brussels sprouts, kohlrabi, broccoli, and cauliflower, while fruits include black and red currants, kiwi, strawberries, wild strawberries, and oranges.

6. Add sources of beta-carotene to your meals, such as: carrots, apricots, kale, spinach, plums, parsley, pumpkin, melon, peaches.

COMPENSATING IRON DEFICIENCY

Iron deficiency is not addressed through diet, but an appropriate diet plays an important role in preventing recurrence of deficiency.

Iron supplementation should be continued until the ferritin level is optimal, at least 70 and/or higher.

It is worth adding the following to oral iron supplementation:

1. Lactoferrin, which reduces gastrointestinal side effects associated with iron supplementation. Adding lactoferrin to iron supplementation helps rebuild iron (ferritin) stores to a greater extent than iron supplementation alone;

2. Vitamin C, which increases iron bioavailability in a dose-dependent manner. Taking 100 mg of vitamin C with a meal has been shown to increase iron absorption by up to 67%;

3. In case of deficiency of B vitamins also B Complex;

4. Probiotic therapy using e.g. Lactobacillus plantarum, Lactobacillus acidophilus, Bifidobacterium longum, which also improve iron absorption.

5. Prebiotics, including galactooligosaccharides (GOS) and fructooligosaccharides (FOS), which increase the bioavailability of iron and reduce its destructive effect on the intestinal microbiota.

Bibliography:

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