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How does iron work in the body. Iron’s Vital Role in Human Health: Functions, Sources, and Deficiency Risks

by alexxlab

How does iron contribute to bodily functions. What are the recommended daily iron intakes for different age groups. Which foods provide the best sources of iron. Why is iron deficiency a concern for certain populations. How can iron supplementation support overall health.

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The Essential Functions of Iron in the Human Body

Iron plays a crucial role in maintaining optimal health and bodily functions. This mineral is indispensable for various physiological processes, making it essential to understand its importance and ensure adequate intake.

What are the primary functions of iron in the body? Iron is a key component in the production of hemoglobin, a protein found in red blood cells that transports oxygen from the lungs to tissues throughout the body. Additionally, iron is vital for the formation of myoglobin, a protein that supplies oxygen to muscles. Beyond these well-known roles, iron also contributes to the synthesis of certain hormones, supporting overall endocrine function.

Oxygen Transport and Utilization

How does iron facilitate oxygen transport? The iron-containing hemoglobin in red blood cells binds to oxygen molecules in the lungs. As blood circulates, it releases this oxygen to cells and tissues that require it for energy production and various metabolic processes. This efficient oxygen delivery system is crucial for maintaining cellular respiration and overall bodily functions.

Muscle Function and Energy Production

What role does iron play in muscle function? Myoglobin, an iron-rich protein found in muscle tissue, acts as an oxygen reservoir. It stores and releases oxygen as needed during muscle contraction, ensuring that muscles have a constant supply of oxygen, even during intense physical activity. This process is essential for maintaining muscle endurance and preventing fatigue.

Recommended Daily Iron Intake: Age and Gender Considerations

Iron requirements vary significantly based on age, sex, and dietary preferences. Understanding these differences is crucial for maintaining optimal iron levels and preventing deficiency or excess.

Iron Needs Across the Lifespan

  • Infants (0-6 months): 0.27 mg
  • Children (1-3 years): 7 mg
  • Children (4-8 years): 10 mg
  • Adolescent boys (14-18 years): 11 mg
  • Adolescent girls (14-18 years): 15 mg
  • Adult men (19-50 years): 8 mg
  • Adult women (19-50 years): 18 mg
  • Adults (51 years and older): 8 mg

Why do women of reproductive age require more iron? Women between 19 and 50 years old need significantly more iron than men due to menstrual blood loss. The recommended daily intake for this group is 18 mg, more than twice the amount required by adult men.

Special Considerations for Pregnancy and Breastfeeding

How do iron needs change during pregnancy? Pregnant women require 27 mg of iron daily, a substantial increase from the non-pregnant state. This higher requirement supports the increased blood volume during pregnancy and ensures proper fetal development. Breastfeeding women need slightly less, with a recommended intake of 9-10 mg per day.

Dietary Sources of Iron: Heme vs. Non-Heme Iron

Iron in food exists in two forms: heme and non-heme iron. Understanding the differences between these forms and their dietary sources is crucial for optimizing iron intake and absorption.

Heme Iron Sources

What foods contain heme iron? Heme iron is found exclusively in animal products, including:

  • Lean red meat
  • Poultry
  • Fish and seafood
  • Organ meats (e.g., liver)

Heme iron is more readily absorbed by the body, with an absorption rate of about 15-35%.

Non-Heme Iron Sources

Where can non-heme iron be found? Non-heme iron is present in plant-based foods and iron-fortified products, such as:

  • Legumes (beans, lentils, chickpeas)
  • Dark leafy greens (spinach, kale)
  • Nuts and seeds
  • Whole grains
  • Iron-fortified cereals and breads

Non-heme iron has a lower absorption rate, typically around 2-20%. However, its absorption can be enhanced by consuming it alongside vitamin C-rich foods or heme iron sources.

Factors Affecting Iron Absorption and Utilization

Several factors can influence the body’s ability to absorb and utilize iron from dietary sources. Understanding these factors can help optimize iron intake and prevent deficiency.

Enhancers of Iron Absorption

How can iron absorption be improved? Certain dietary components and practices can enhance iron absorption:

  • Vitamin C: Consuming vitamin C-rich foods alongside iron sources can significantly increase non-heme iron absorption.
  • Meat, fish, and poultry: These foods not only provide heme iron but also enhance the absorption of non-heme iron when consumed together.
  • Fermented foods: The lactic acid in fermented foods may improve iron absorption.

Inhibitors of Iron Absorption

What factors can hinder iron absorption? Several compounds can interfere with iron absorption:

  • Phytates: Found in whole grains, legumes, and nuts
  • Polyphenols: Present in tea, coffee, and some fruits and vegetables
  • Calcium: High calcium intake may inhibit iron absorption
  • Oxalates: Found in spinach, chocolate, and some other foods

To maximize iron absorption, it’s advisable to consume iron-rich foods separately from these inhibitors when possible.

Iron Deficiency: Causes, Symptoms, and Risk Factors

Iron deficiency is the most common nutritional deficiency worldwide, affecting millions of people. Recognizing the causes, symptoms, and risk factors is crucial for early detection and prevention.

Common Causes of Iron Deficiency

What are the primary reasons for iron deficiency? Several factors can lead to insufficient iron levels:

  • Inadequate dietary intake
  • Blood loss (e.g., heavy menstrual periods, gastrointestinal bleeding)
  • Increased iron requirements (e.g., during pregnancy or rapid growth periods)
  • Malabsorption disorders (e.g., celiac disease, inflammatory bowel disease)
  • Chronic diseases that affect iron metabolism

Recognizing Iron Deficiency Symptoms

How does iron deficiency manifest in the body? Common symptoms include:

  • Fatigue and weakness
  • Pale skin
  • Shortness of breath
  • Dizziness
  • Cold hands and feet
  • Brittle nails
  • Unusual cravings for non-food items (pica)

It’s important to note that symptoms may develop gradually and can be mistaken for other conditions. Consulting a healthcare provider for proper diagnosis is crucial.

Iron Supplementation: Benefits and Considerations

While obtaining iron from dietary sources is ideal, supplementation may be necessary for some individuals to prevent or treat iron deficiency. Understanding the benefits and potential risks of iron supplementation is essential for making informed decisions about its use.

Types of Iron Supplements

What forms of iron are commonly used in supplements? Iron supplements are available in various forms, including:

  • Ferrous sulfate
  • Ferrous gluconate
  • Ferric citrate
  • Ferric sulfate

Each form has different iron content and absorption rates. Ferrous forms are generally better absorbed than ferric forms.

Potential Benefits of Iron Supplementation

How can iron supplements improve health? For individuals with iron deficiency, supplementation can:

  • Correct anemia and improve oxygen transport
  • Reduce fatigue and increase energy levels
  • Enhance cognitive function and mood
  • Support immune system function
  • Improve exercise performance and endurance

Precautions and Side Effects

What should be considered when taking iron supplements? While iron supplementation can be beneficial, it’s important to be aware of potential side effects and precautions:

  • Gastrointestinal discomfort (nausea, constipation, diarrhea)
  • Risk of iron overload in certain individuals
  • Interactions with other medications or supplements
  • Potential for accidental overdose, especially in children

Always consult with a healthcare provider before starting iron supplementation to determine the appropriate dosage and form based on individual needs and health status.

Iron’s Role in Special Populations: Pregnancy, Infancy, and Athletics

Certain populations have unique iron requirements due to physiological demands or increased risk of deficiency. Understanding these specific needs is crucial for maintaining optimal health in these groups.

Iron During Pregnancy and Fetal Development

Why is iron particularly important during pregnancy? Adequate iron intake during pregnancy is critical for several reasons:

  • Supports the increased maternal blood volume
  • Ensures proper fetal growth and development
  • Reduces the risk of preterm birth and low birth weight
  • Helps prevent maternal anemia and associated complications

Pregnant women often require iron supplementation in addition to dietary sources to meet their increased needs of 27 mg per day.

Iron Needs in Infancy and Early Childhood

How do iron requirements change during early life stages? Infants and young children have high iron needs due to rapid growth and development:

  • Full-term infants typically have sufficient iron stores for the first 4-6 months of life
  • Breastfed infants may require iron supplementation starting at 4 months
  • Iron-fortified infant cereals and pureed meats are important sources of iron for older infants
  • Toddlers and young children should consume a variety of iron-rich foods to support cognitive and physical development

Iron and Athletic Performance

What role does iron play in athletic performance? Athletes, especially endurance athletes and female athletes, may have increased iron needs due to:

  • Increased red blood cell production
  • Iron losses through sweat and gastrointestinal bleeding
  • Potential for exercise-induced hemolysis (destruction of red blood cells)

Adequate iron levels are crucial for optimal oxygen delivery to muscles, energy production, and overall athletic performance. Athletes should work with healthcare providers or sports nutritionists to ensure their iron intake meets their specific needs.

Monitoring Iron Status: Tests and Diagnostic Approaches

Regular monitoring of iron status is essential for individuals at risk of deficiency or those with known iron-related disorders. Understanding the various tests and diagnostic approaches can help in early detection and management of iron imbalances.

Common Iron Status Tests

What tests are used to assess iron levels in the body? Healthcare providers may use several tests to evaluate iron status:

  • Hemoglobin and hematocrit: Measures the amount and percentage of red blood cells
  • Serum ferritin: Indicates iron stores in the body
  • Transferrin saturation: Assesses the amount of iron bound to transferrin protein
  • Total iron-binding capacity (TIBC): Measures the blood’s capacity to bind transferrin with iron
  • Soluble transferrin receptor (sTfR): Helps distinguish between iron deficiency anemia and anemia of chronic disease

Interpreting Iron Test Results

How are iron test results interpreted? Interpretation of iron status tests requires consideration of multiple factors:

  • Low hemoglobin and hematocrit levels may indicate anemia
  • Low serum ferritin typically suggests depleted iron stores
  • High TIBC and low transferrin saturation often indicate iron deficiency
  • Elevated sTfR levels can help confirm iron deficiency, even when ferritin levels are normal due to inflammation

It’s important to note that a comprehensive evaluation of iron status often requires multiple tests and consideration of an individual’s overall health and risk factors.

Frequency of Iron Status Monitoring

How often should iron levels be checked? The frequency of iron status monitoring depends on individual risk factors and health conditions:

  • Healthy adults: May be checked as part of routine health screenings
  • Pregnant women: Often tested at the first prenatal visit and again in the second or third trimester
  • Individuals with chronic conditions affecting iron metabolism: May require more frequent monitoring
  • Athletes: May benefit from periodic testing, especially if symptoms of deficiency are present

Healthcare providers can recommend appropriate screening intervals based on individual circumstances and risk factors.

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What is iron and what does it do?

Iron is a mineral that the body needs for growth and development. Your body uses iron to make hemoglobin, a protein in red blood cells that carries oxygen from the lungs to all parts of the body, and myoglobin, a protein that provides oxygen to muscles. Your body also needs iron to make some hormones.

How much iron do I need?

The amount of iron you need each day depends on your age, your sex, and whether you consume a mostly plant-based diet. Average daily recommended amounts are listed below in milligrams (mg). Vegetarians who do not eat meat, poultry, or seafood need almost twice as much iron as listed in the table because the body doesn’t absorb nonheme iron in plant foods as well as heme iron in animal foods.
















Life StageRecommended Amount
Birth to 6 months0. 27 mg
Infants 7–12 months11 mg
Children 1–3 years7 mg
Children 4–8 years10 mg
Children 9–13 years8 mg
Teen boys 14–18 years11 mg
Teen girls 14–18 years15 mg
Adult men 19–50 years8 mg
Adult women 19–50 years18 mg
Adults 51 years and older8 mg
Pregnant teens27 mg
Pregnant women27 mg
Breastfeeding teens10 mg
Breastfeeding women9 mg

What foods provide iron?

Iron is found naturally in many foods and is added to some fortified food products. You can get recommended amounts of iron by eating a variety of foods, including the following:

  • Lean meat, seafood, and poultry.

  • Iron-fortified breakfast cereals and breads.

  • White beans, lentils, spinach, kidney beans, and peas.

  • Nuts and some dried fruits, such as raisins.

Iron in food comes in two forms: heme iron and nonheme iron. Nonheme iron is found in plant foods and iron-fortified food products. Meat, seafood, and poultry have both heme and nonheme iron.

Your body absorbs iron from plant sources better when you eat it with meat, poultry, seafood, and foods that contain vitamin C, such as citrus fruits, strawberries, sweet peppers, tomatoes, and broccoli.

What kinds of iron dietary supplements are available?

Iron is available in many multivitamin-mineral supplements and in supplements that contain only iron. Iron in supplements is often in the form of ferrous sulfate, ferrous gluconate, ferric citrate, or ferric sulfate. Dietary supplements that contain iron have a statement on the label warning that they should be kept out of the reach of children. Accidental overdose of iron-containing products is a leading cause of fatal poisoning in children under 6.

Am I getting enough iron?

Most people in the United States get enough iron. However, certain groups of people are more likely than others to have trouble getting enough iron:

  • Teen girls and women with heavy periods.

  • Pregnant women and teens.

  • Infants (especially if they are premature or low-birth weight).

  • Frequent blood donors.

  • People with cancer, gastrointestinal (GI) disorders, or heart failure.

What happens if I don’t get enough iron?

In the short term, getting too little iron does not cause obvious symptoms. The body uses its stored iron in the muscles, liver, spleen, and bone marrow. But when levels of iron stored in the body become low, iron deficiency anemia sets in. Red blood cells become smaller and contain less hemoglobin. As a result, blood carries less oxygen from the lungs throughout the body.

Symptoms of iron deficiency anemia include GI upset, weakness, tiredness, lack of energy, and problems with concentration and memory. In addition, people with iron deficiency anemia are less able to fight off germs and infections, to work and exercise, and to control their body temperature. Infants and children with iron deficiency anemia might develop learning difficulties.

Iron deficiency is not uncommon in the United States, especially among young children, women under 50, and pregnant women. It can also occur in people who do not eat meat, poultry, or seafood; lose blood; have GI diseases that interfere with nutrient absorption; or eat poor diets.

What are some effects of iron on health?

Scientists are studying iron to understand how it affects health. Iron’s most important contribution to health is preventing iron deficiency anemia and resulting problems.

Pregnant women

During pregnancy, the amount of blood in a woman’s body increases, so she needs more iron for herself and her growing baby. Getting too little iron during pregnancy increases a woman’s risk of iron deficiency anemia and her infant’s risk of low birth weight, premature birth, and low levels of iron. Getting too little iron might also harm her infant’s brain development.

Women who are pregnant or breastfeeding should take an iron supplement as recommended by an obstetrician or other health care provider.

Infants and toddlers

Iron deficiency anemia in infancy can lead to delayed psychological development, social withdrawal, and less ability to pay attention. By age 6 to 9 months, full-term infants could become iron deficient unless they eat iron-enriched solid foods or drink iron-fortified formula.

Anemia of chronic disease

Some chronic diseases—such as rheumatoid arthritis, inflammatory bowel disease, and some types of cancer—can interfere with the body’s ability to use its stored iron. Taking more iron from foods or supplements usually does not reduce the resulting anemia of chronic disease because iron is diverted from the blood circulation to storage sites. The main therapy for anemia of chronic disease is treatment of the underlying disease.

Can iron be harmful?

Yes, iron can be harmful if you get too much. In healthy people, taking high doses of iron supplements (especially on an empty stomach) can cause an upset stomach, constipation, nausea, abdominal pain, vomiting, and diarrhea. Large amounts of iron might also cause more serious effects, including inflammation of the stomach lining and ulcers. High doses of iron can also decrease zinc absorption. Extremely high doses of iron (in the hundreds or thousands of mg) can cause organ failure, coma, convulsions, and death. Child-proof packaging and warning labels on iron supplements have greatly reduced the number of accidental iron poisonings in children.

Some people have an inherited condition called hemochromatosis that causes toxic levels of iron to build up in their bodies. Without medical treatment, people with hereditary hemochromatosis can develop serious problems such as liver cirrhosis, liver cancer, and heart disease. People with this disorder should avoid using iron supplements and vitamin C supplements.

The daily upper limits for iron include intakes from all sources—food, beverages, and supplements—and are listed below. A doctor might prescribe more than the upper limit of iron to people who need higher doses for a while to treat iron deficiency.






AgesUpper Limit
Birth to 12 months40 mg
Children 1–13 years40 mg
Teens 14–18 years45 mg
Adults 19+ years45 mg


 

Does iron interact with medications or other dietary supplements?

Yes, iron supplements can interact or interfere with medicines and other supplements you take. Here are several examples:

  • Iron supplements can reduce the amount of levodopa that the body absorbs, making it less effective. Levodopa, found in Sinemet® and Stalevo®, is used to treat Parkinson’s disease and restless leg syndrome.

  • Taking iron with levothyroxine can reduce this medication’s effectiveness. Levothyroxine (Levothroid®, Levoxyl®, Synthroid®, Tirosint®, and Unithroid®) is used to treat hypothyroidism, goiter, and thyroid cancer.

  • The proton pump inhibitors lansoprazole (Prevacid®) and omeprazole (Prilosec®) decrease stomach acid, so they might reduce the amount of nonheme iron that the body absorbs from food.

  • Calcium might interfere with iron absorption. Taking calcium and iron supplements at different times of the day might prevent this problem.

Tell your doctor, pharmacist, and other health care providers about any dietary supplements and prescription or over-the-counter medicines you take. They can tell you if the dietary supplements might interact with your medicines or if the medicines might interfere with how your body absorbs, uses, or breaks down nutrients.

Iron and healthful eating

People should get most of their nutrients from food and beverages, according to the federal government’s Dietary Guidelines for Americans. Foods contain vitamins, minerals, dietary fiber, and other components that benefit health. In some cases, fortified foods and dietary supplements are useful when it is not possible to meet needs for one or more nutrients (for example, during specific life stages such as pregnancy). For more information about building a healthy dietary pattern, see the Dietary Guidelines for Americans and the U.S. Department of Agriculture’s MyPlate.

Where can I find out more about iron?

  • For general information on iron:
    • Office of Dietary Supplements Health Professional Fact Sheet on Iron

    • MedlinePlus®, Iron and Iron in diet

  • For more information on food sources of iron:
    • U.S. Department of Agriculture’s (USDA) FoodData Central

    • USDA, Nutrient List for Iron (listed by food or by iron content)

  • For more advice on choosing dietary supplements:
    • Office of Dietary Supplements Frequently Asked Questions: Which brand(s) of dietary supplements should I purchase?

  • For information about building a healthy dietary pattern:
    • MyPlate

    • Dietary Guidelines for Americans

Disclaimer

This fact sheet by the National Institutes of Health (NIH) Office of Dietary Supplements (ODS) provides information that should not take the place of medical advice. We encourage you to talk to your health care providers (doctor, registered dietitian, pharmacist, etc.) about your interest in, questions about, or use of dietary supplements and what may be best for your overall health. Any mention in this publication of a specific product or service, or recommendation from an organization or professional society, does not represent an endorsement by ODS of that product, service, or expert advice.


Updated:
April 5, 2022
History of changes to this fact sheet

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Why iron is needed in the human body

Published: 23.10.2021

Iron is a vital trace element for the body that regulates oxygen metabolism, participates in redox reactions, synthesis of hormones and enzymes, supports the functioning of the nervous and immune systems and performs a number of other functions 1 .


Iron deficiency can lead to serious disorders of the internal organs, including the development of iron deficiency anemia. How to support the body and prevent the development of an iron deficiency state, we will tell in this article.


What are the functions of iron in the human body?

Iron is part of hemoglobin, a complex protein that is an important component of red blood cells. Hemoglobin contains about 60-70% of the total amount of iron in the body. In addition to red blood cells, iron is also part of iron-containing enzymes (peroxidase, cytochrome oxidase, catalase) and proteins (ferritin, transferrin), which are involved in cholesterol and energy metabolism, generation of nerve impulses, immune processes, redox reactions. Thus, the most important functions of iron in the human body are:

  • Ensuring cellular respiration. The transport of oxygen to cells is the main function of iron. As we have already noted, iron is part of hemoglobin, which, when inhaled, combines with oxygen in the lungs, after which red blood cells carry it throughout the body. Iron deficiency can lead to oxygen starvation of cells and, as a result, to many somatic disorders.

  • Synthesis of ATP and enzymes. Adenosine triphosphate (ATP) provides energy for many processes that occur in cells, such as muscle contraction, transmission of nerve impulses, and chemical synthesis. With a lack of iron, the production of ATP is disrupted, the deficiency of which triggers a whole chain of pathological reactions 2 . In addition to the production of ATP, iron is involved in the synthesis of DNA, cytochromes and enzymes, and also ensures the metabolism of collagen – a key element in maintaining beauty and youth 3.4 .

  • Regulation of the immune system. Iron has an important effect on the function and differentiation of immune cells, is involved in the regulation of cytokines, and activates the immune response. Iron deficiency leads to a decrease in the number of immune cells and their functional activity 5. 6 .

  • Regulation of thyroid function. Along with iodine and copper, iron plays an important role in the synthesis of thyroid hormones. The lack of these micronutrients can lead to the development of autoimmune pathologies 7 .

  • Support for the nervous system. Iron provides the synthesis of neurotransmitters – biologically active substances that are responsible for the transmission of nerve impulses between neurons. In addition, iron is involved in the myelination of nerve fibers and affects the function of the hypothalamus 8 . With iron deficiency anemia, motor activity and cognitive abilities are reduced, and the psycho-emotional state is disturbed.

Signs of iron deficiency

The risk group for the development of iron deficiency anemia includes women (due to monthly blood loss during menstruation) 9 , pregnant and lactating women (due to the high need for micronutrients) 10 , children and adolescents (due to the high needs of a growing organism), and also people with chronic diseases of the gastrointestinal tract, occurring with impaired absorption.

There are no specific signs of an iron deficiency state. However, the following symptoms may indicate an iron deficiency:

  • constant fatigue;
  • high fatigue;
  • psycho-emotional instability;
  • decreased concentration;
  • recurring dizziness and headaches;
  • sleep disturbance;
  • pale skin;
  • dry chapped lips;
  • fragile nails with longitudinal grooves;
  • change in taste and smell;
  • muscle pain and cramps.

These symptoms do not necessarily indicate an iron deficiency condition, but require the attention of doctors. If you observe three or more signs in yourself, you should seek medical help and be examined. Laboratory tests can detect iron deficiency.

How to prevent iron deficiency?

The best way to prevent iron deficiency is a balanced diet, so first of all, you need to analyze your diet and include foods rich in iron: nuts (pistachios, cashews, peanuts, pine nuts), pork liver, lentils, spinach, buckwheat, peas, black chocolate.

During periods of high iron demand and in situations where nutritional balance is not possible, dietary supplements can help maintain adequate levels of the micronutrient.

Which iron is better absorbed by the body?

When choosing iron preparations, attention should be paid to the form of the product and its compliance with the GMP standard.

In modern dietary supplements, iron is present in various forms: lactate, gluconate, sulfate, chelate, and others. They differ in the degree of assimilation by the body. Chelates 11 have high bioavailability.

Chelated iron

Chelated compounds contain the amino acids that are needed for their absorption, so the body does not need to spend time and energy processing chelated iron. You are taking a mineral that is ready to be absorbed as quickly and easily as possible. It is due to amino acids that chelates do not cause digestive disorders, since they do not affect the level of stomach acidity, and also do not accumulate in blood vessels, kidneys, and joints. And most importantly, the body easily tolerates chelated minerals in large dosages.

“Iron Chelate Evalar”

The Evalar company produces readily available chelated iron, which meets the high international GMP quality standard. “Iron Chelate Evalar” can compensate for iron deficiency during a period of high demand, ensure maximum absorption of the trace element without deposition in the kidneys, joints and blood vessels. The dietary supplement is recommended for adults and children over 14 years of age, is allowed for pregnant and lactating women.

The course intake of “Iron Chelate Evalar” can help maintain a normal level of hemoglobin, reduce the risk of developing iron deficiency anemia, and increase efficiency. To meet the body’s need for iron, it is enough to take 1 tablet per day with meals. The duration of admission is at least 2 months.


Liposomal iron

Recently, an innovative liposomal form of iron has appeared on the pharmaceutical market, in which the trace element is in a protective environment of liposomes and does not come into contact with the gastrointestinal mucosa. The liposomal form eliminates the possibility of free iron entering the intestinal lumen, its contact with the mucosa and its local irritation with the development of side effects.

Due to the similarity with natural cell membranes in terms of chemical composition, liposomal iron has the highest degree of assimilation and is well tolerated by the body, without causing side effects from the digestive organs 12.13 .

In the assortment of the Evalar company, iron in liposomal form is presented in the dietary supplements Liposomal Iron 30 mg and Liposomal Iron Plus.

Liposomal iron 30 mg

“Iron liposomal 30 mg” – unique 14
a combination of liposomal iron and bioavailable vitamins C, B 9 , B 12 , designed to compensate for micronutrient deficiencies, increase hemoglobin and ferritin levels.

Iron in liposomal form is easily absorbed without damaging the mucous membrane of the stomach and intestines, is highly effective and well tolerated. The vitamins included in the dietary supplement can improve the absorption of iron, have a positive effect on the cardiovascular, nervous and immune systems of the body.

For the prevention of anemia, adults are advised to take 1 capsule daily with meals. If iron deficiency is detected, the daily dosage may be increased by the attending physician, depending on the test results.

Liposomal Iron Plus

Vitamin-mineral complex contains liposomal iron and vitamins C, B 6 , B 9 , B 12 , is available in an easy-to-take form of effervescent tablets with a pleasant taste of blackcurrant.

The Liposomal Iron Plus complex does not irritate the mucous membrane of the digestive organs and can contribute to:

  • replenishment of iron deficiency during periods of increased body demand for micronutrients and in iron deficiency states;
  • normalization of the process of hematopoiesis, hemoglobin and ferritin levels;
  • increase of working capacity, physical activity;
  • strengthening immunity.

Adults are advised to take 1-2 tablets per day, after dissolving them in a glass of water. The duration of the course is at least 1 month. Before taking a dietary supplement, it is advisable to consult with your doctor or nutritionist.

Updated: 09.12.2022

1 Mechanistic and regulatory aspects of intestinal iron absorption. Gulets S., Anderson G. D., Collins D. F. Am J Physiol Gastrointest Liver Physiol. 2014 Aug 15;307(4):G397-409. doi:
10.1152/ajpgi.00348.2013 . Epub 2014 Jul 3. PMID: 24994858; PMCID:
PMC4137115 .
2 s for Myelination and Remyelination. Celi V. T., Correale D., Paes P. M., Pasquini J. M. ASN Neuro. 2020 Jan-Dec;12:1759091420962681 doi:
10.1177/1759091420962681 . PMID: 32993319; PMCID:
PMC7545512 .
3 Federal clinical guidelines for the diagnosis and treatment of iron deficiency anemia / A. G. et al. — 2015.
4 Effect of iron-deficient diets on the formation of bone tissue. VoprPitan 1984; (5): 55-915. Mamedov LA, Kosaganova NIu, Rikhireva GT et al. Changes in the content of transferrin, ceruloplasmin, iron, and copper in blood serum and granulation tissue in wound healing in an experiment. Patol Fiziol Eksp Ter 1988; 4:58-61.
5 Stephen, J Oppenheimer Iron and Its Relation to Immunity and Infectious Disease / J. Stephen Oppenheimer // J. Nutr. – 2001. – No. 131. – P. 616–635.
6 Iron in immune cell function and host defense. Haska D, Hoffmann A, Weiss G. Semin Cell Dev Biol. 2021 Jul;115:27-36. doi:
10.1016/j.semcdb.2020.12.005 . Epub 2020 Dec 30. PMID: 33386235.
7 Thyroid-Gut Axis: How Does the Microbiota Affect Thyroid Function?/ Thyroid-Gut -Axis: How Does the Microbiota Influence Thyroid Function? Knezevic J. , Starchl K., Berisha A. T., Amrein K. Nutrients. 2020 Jun 12;12(6):1769. doi:
10.3390/nu12061769 . PMID: 32545596; PMCID:
PMC7353203 .
8 John L. Beard. Iron biology in immune function, muscle metabolism and neuronal functioning//J of Nutrition. 2001; 131:568–580.
9 Konovodova E. N., Dokueva R. S.-E., Yakunina N. A. Iron deficiency conditions in obstetric and gynecological practice // BC. 2011; 20:1228–1231.
10 Kozuki N, Lee AC, Katz J. Child Health Epidemiology Reference Group. Moderate to severe, but not mild, maternal anemia is associated with increased risk of small-for-gestation-al-age outcomes. J. Nutr., 2012, 142(2): 358-62.
11 Report on the implementation of research work on the topic: “Chelated forms of minerals (calcium, magnesium, iron, zinc, copper) – the mechanism of action and the benefits of using biologically active additives in the production (literature review, clinical trials)” / BTI (branch) FSBEI HE “Altai State Technical University named after. I.I. Polzunov “- Biysk. – 2019
12 Gregoriadis. G. (1995) TIBECH. 13, 527-537.
13 Yurasov V.V., Kucheryanu V.G.,. Kryzhanovsky G.N. et al. (1996) Progress in Drug Delivery Systems. Biomedical Research Foundation, Tokyo. Eds. Sadao Hirota, 5, 171-174.
14 In the assortment of ZAO Evalar.

Iron: which foods are high in iron content table

05 May 2023

491

Ekaterina Slobodyanyuk

I have been working as a nutrition consultant since 2018, I am a member of the NGO “Nutritionists of Russia”, I participate in international conferences and congresses.

I collaborate with various projects in the field of nutrition:

  • Sfera.fm
  • Kale coach
  • course and club Chemistry of Food by Olga Kosnikova and Zinaida Medvedeva

I teach nutrition at the NSL Knowledge League and participate in the development of a nutrition course for the Moscow Triathlon School.

Iron is one of the most famous micronutrients, without which the life of every person is impossible. As early as the 16th century, the full-fledged use of iron for the treatment of iron deficiency conditions, namely anemia, began, but only in the 19In 1932, it was proved that iron has irrefutable value for the treatment of a special form of iron deficiency anemia – chlorosis. Today, the relevance of iron deficiency in the diet of people remains no less acute both for an adult healthy person and for risk groups, that is, for pregnant women, for young children and people with certain diseases. Therefore, it is important to understand the food sources of iron, its norms for different ages, and its other features.

Content of Article

What is the use of iron?

In order to understand the norms of iron intake and the significance of these norms, you need to know why our body needs this microelement at all? Why is it irreplaceable and what vital functions does it perform?

Hemoglobin formation

Definitely, you need to start with a function that is rightfully considered the leading and most famous. Iron is a key element for the formation of hemoglobin, a protein that is the main component of erythrocytes (red blood cells) and helps them carry oxygen from the lungs to all cells, tissues and organs of the body. Thanks to this, it is possible not only to saturate the whole organism with oxygen, and therefore, in general, its existence, but also to maintain the acid-base balance of the blood.

Muscle development

For muscles, iron is also an indispensable component, because. used to form myoglobin – a protein that stores oxygen in the muscles and uses it during work.

Photo by Jenny Hill on Unsplash

Brain Improvement

In addition to carrying out the work of the muscles of the body, iron also carries oxygen to the brain, which is crucial for both physical and mental performance. Insufficient intake of iron with food for a long time can affect the efficiency of thought processes, which leads to a decrease in concentration, increased irritability, and a decrease in efficiency, because. the brain thus will not be able to get enough energy.

Restless legs syndrome prevention

Willis-Ekbom disease, or restless legs syndrome, is a condition that causes a person to have an uncontrollable desire to move their legs, which occurs most often in the evening or at night when the person is sitting or lying down. In order to reduce the likelihood of this syndrome, it is important to control the level of iron in the body.

Immunity booster

It is no secret that a complete and balanced diet in itself is an important factor in the prevention of infectious and non-communicable diseases, but it is worth saying a few words separately about the role of iron for the immune system: it is involved in the work of innate immunity and resists bacterial infections, contributes to the correct the work of acquired immunity, participating in the process of maturation of T-lymphocytes, and also provides vital metabolic processes in the body.

Healthy heart

Iron deficiency anemia can lead to fast or irregular heartbeat. This is due to the fact that the heart has to pump more blood to compensate for the lack of oxygen and cover the body’s needs for it. This can lead to an enlarged heart and heart failure. Therefore, prevention of iron deficiency will help protect the heart from these consequences.

Healthy pregnancy

During pregnancy, a woman’s body increases blood volume and red blood cell production. This is necessary in order to provide the growing fetus with the necessary nutrients and oxygen. Accordingly, the need for iron is also growing. When it is insufficiently supplied with food or in the form of drugs prescribed by a doctor, or in diseases in connection with which the absorption of iron by the body is impaired, the risk of premature birth, cognitive impairment in a child at birth, and underweight is increased.

Photo by Alicia Petresc on Unsplash

Therefore, it is very important to prevent iron deficiency and control its levels and intake both before and during pregnancy.

Iron requirements of the body

The average recommendations for adults aged 18-50 are in the range of 10-20 mg, but if we consider individual norms from a number of health organizations in the world, then we can highlight certain iron indicators that need to be received per day:

Children and teenagers:

  • 1-3 years 7 mg iron;
  • 4-8 years – 10 mg;
  • 9-13 years – 8 mg;
  • boys 14-18 years old – 11 mg;
  • girls 14-18 years old – 15 mg.

Men 18 years and older – 8 mg.

Women:

  • 18-50 years – 18 mg;
  • 50 years and older – 8 mg;
  • during pregnancy – 27 mg;

It is important to note here that it is important to obtain this amount of iron from the daily diet and various food sources containing this trace element, namely from foods rich in iron.

What is the danger of iron deficiency in the body and how to determine it?

If there is not enough iron in the diet or if it is poorly absorbed, then the body will begin to rely on internal iron stores to maintain sufficient levels in the most important parts – the blood and muscles. The full manifestation of iron deficiency will be determined symptomatically during the progression of iron deficiency anemia.

Iron deficiency anemia is a condition in which the body’s iron stores are so low that there may not be enough healthy red blood cells to carry oxygen efficiently. Accordingly, there is not enough hemoglobin in the body.

Causes of iron deficiency

Some of the most common causes of iron deficiency are:

Pregnancy and childhood

If before pregnancy the woman was not prevented or treated for micronutrient deficiencies, including iron. In addition, as mentioned earlier, iron should cover not only the needs of the woman herself, but also the needs of the fetus. In newborns and infants, iron deficiency can be associated in most cases with a lack of it during fetal development. In addition, children are prone to physiological anemia, a condition that occurs in a child due to accelerated growth in the first year of life.

Iron deficiency in the human diet

People sometimes underestimate the importance of obtaining micronutrients from the foods they eat. This is especially true for an unbalanced diet in vegans and vegetarians, but if you consume enough heme and non-heme iron, or adjust the iron diet depending on your taste preferences, you can prevent the occurrence or development of iron deficiency.

Diseases of the gastrointestinal tract with reduced iron absorption

Iron from food is absorbed in the small intestine, and hypoacid gastritis, enteritis, and celiac disease can disrupt this process. In addition, the cause may be the surgical removal of part of the small intestine. It is important to consult a doctor and undergo examinations in time and treat diseases of the stomach and intestines so that they do not progress to serious consequences.

Blood loss

Since red blood cells contain iron, bleeding is accompanied by iron loss to varying degrees, especially women with heavy menstruation, as well as people with slow chronic blood loss due to peptic ulcer, hiatal hernia, colon polyposis, hemorrhoids or colorectal cancer. Also, uncontrolled use of non-steroidal anti-inflammatory drugs, such as ibuprofen and aspirin, carries risks.

Symptoms of iron deficiency

  • fatigue and lack of energy
  • shortness of breath
  • palpitations (tachycardia)
  • chest pain
  • cold hands and feet
  • pale skin

Photo by Gregory Pappas on Unsplash

Less common but also important symptoms:

  • headache
  • dizziness
  • ringing in the ears
  • hair loss, especially when combing and washing
  • pain in the tongue, inflammation
  • difficulty swallowing (dysphagia)
  • ulcers at the corners of the mouth
  • nails become brittle
  • muscle weakness
  • perversion of taste and smell preferences (there is a desire to eat paper, ice, chalk, like the smell of paint, chemicals, gasoline)
  • restless leg syndrome
  • Infants and children with iron deficiency often have poor appetite

Based on even a part of these symptoms and complaints of a person, the doctor can refer him to the necessary tests and examinations to confirm or refute the diagnosis, and if present, prescribe the necessary treatment and nutritional correction.

Can there be too much iron in the body?

A lot has been said about iron deficiency, but not many people know that an excess of iron in the body can also be dangerous. This is most often the case with glandular supplements and medications, so it is important to check with your doctor before taking them.

Depending on the drug, the highest dose varies between 20-40 mg of iron, but as early as 20 mg side effects may appear:

  • feeling of lethargy, malaise
  • fatigue
  • abdominal pain
  • constipation etc.

But most importantly, very high doses of iron supplements can be fatal, especially when taken by children, so care must be taken not only with children taking iron supplements, but also with storing them at home.

Iron absorption

Since the diet of any person consists of many nutrients from proteins, fats and carbohydrates, to various minerals and vitamins, it is necessary to know what nutritional factors can affect the absorption of iron from foods. This information is especially important for people from risk groups who have not yet built a balanced and rational diet for themselves.

Interfere with iron absorption:

  • phytic acid (found in legume seeds, whole grains)
  • polyphenols (in tea, coffee, cocoa, red wine, some vegetables and legumes)
  • calcium in products

But it is important to understand that some of these substances will be minimized through heat treatment, therefore, it is definitely not worth excluding these products from your diet just like that!

In addition, interfere:

  • proton pump inhibitors, omeprazole
  • diseases of the stomach and intestines
  • alcohol
  • infectious diseases
  • helminthic infestations

Helps iron absorption

  • vitamin C (particularly helpful in the absorption of non-heme iron)
  • copper (promotes better transport of iron from the depot or after absorption in the small intestine)

Products containing iron

Understanding why we need iron in the body and in what quantities, it is important to know the sources from which it can be obtained.

There are two different types of iron in foods:

  • heme iron found in animal products such as fish or meat;
  • non-heme iron that comes from plant foods such as green leafy vegetables, fruits, seeds, and beans.

The main difference you need to know is that heme iron is absorbed by a person much easier than non-heme iron, but this does not mean that only the first should be preferred, because all products containing iron are important.

The fact is that the bioavailability of this trace element is quite low. According to various sources, heme iron is absorbed by a healthy body by no more than 20-40%, and non-heme iron by 5-15%, regardless of the iron content in foods. And by focusing only on products of the first category, you can really get enough iron, but come to deficiencies in other nutrients.

In order for the body to receive and assimilate iron fully, it is enough to follow the simple principles of nutrition:

1) provide yourself with a balanced diet, that is, get both types of iron with food, which will increase the chances of assimilating it more and better, and, of course, focus on iron-rich foods;

2) use as many different sources of non-heme iron as possible: prepare mixes from various legumes, add seeds to salads, buy whole grain bread;

3) in addition, eating foods rich in vitamin C along with non-heme iron improves its absorption:
spinach salad + peppers
lentils + red peppers and tomato sauce
iron-fortified breakfast cereal + grapefruit.

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Foods high in iron

In general, products containing iron include:

  • meat, poultry, fish
  • cereals
  • legumes
  • egg yolks
  • nuts
  • tofu
  • dark green vegetables
  • potatoes
  • fortified foods

But focus on foods high in iron:

Shellfish

This is a tasty and nutritious food that is a good source of iron: a 100 g serving of shellfish contains about 3 mg of iron. But besides this, shellfish is an easily digestible protein that also contains other trace elements: iodine, calcium, magnesium, as well as vitamin PP and vitamins A and E.

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Spinach

Healthy and low calorie spinach contains non-heme iron – about 2.7 mg per 100 grams of product, but most importantly, it is also rich in vitamin C, which increases the level of absorption of iron, making spinach a great option for any salad or side dish! It is also a high-quality source of vegetable protein, dietary fiber and micronutrients: potassium, iodine, vitamins B, A and E.

Red meat

A satisfying and nutritious protein-rich product with approximately 2.7 mg of iron per 100 gram serving. It is the body’s most readily available source of iron, so those who regularly eat poultry, meat, and fish are thought to be the least likely to develop iron deficiency anemia. This, of course, applies more to completely healthy people, but even they should not forget about other sources.

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Legumes

The most common non-heme irons are lentils, chickpeas, peas, soybeans, dark red beans, and lima beans. According to various sources, 200 grams of boiled lentils contain 4.9-6.6 mg of iron, as well as B vitamins and folic acid. And about 85 grams of boiled beans contain 1.8 grams of iron, along with which there will be vitamin C, and we already know the significance of their compatibility!

Offal

Liver, kidneys, heart – all this can be called extremely nutritious and useful iron-containing foods! For example, calf’s liver contains copper and iron in an easily digestible form, with which it is especially rich. Along with this, it contains a lot of vitamins of groups B, A and C. In addition, 85 g of beef liver provides the body with 4.17 mg of iron. Did you also come up with a salad with spinach, liver, roasted peppers and cherry tomatoes? Imagine how much benefit in such a dish!

How to save iron in food

It has already been said about the importance of the absorption of iron from various foods, but it is necessary to touch upon the moment and the preservation of this trace element during cooking.

First of all, you can use good cast iron cookware for cooking foods containing iron. It is believed that this contributes not only to the preservation of the microelement in food, but can also increase its amount available for absorption.

In addition, you need to pay attention to the heat treatment of products: the shorter the cooking time and the lower the temperature, the more nutrients remain in the food. This rule does not apply to all minerals, but it definitely applies to iron. And a variety of culinary techniques can help with this: blanching, stewing, baking, roasting, steaming, grilling, in a pressure cooker, etc.

The main thing to remember about hygiene and the rules for processing meat and fish products, eggs and other products that require certain preparation and cooking time for their safety!

Prevention of iron deficiency in children

To prevent iron deficiency anemia in infants, it is important to feed your baby breast milk or iron-fortified formula during the first year of life. Sometimes parents make the mistake of giving their baby cow’s milk, but it is not a good source of iron for the baby and in general, it is not recommended for babies under one year of age.

After six months, you can start feeding your baby special baby cereals with cereals and meat purees, they are most often recommended twice a day or more. Further legumes, fish, eggs, etc. may be included. Also, regarding complementary foods, it is important to consult a pediatrician.