Iron: benefits, side effects, dosage and interactions (2023)

Iron has many benefits and is one of the most important minerals for your body. The body needs iron to make hemoglobin, which helps red blood cells carry oxygen throughout the body, and myoglobin, a protein that helps carry oxygen to muscle cells.

Although all human cells contain iron, it is found primarily in red blood cells.

Iron supplements play a particularly important role in the treatment of anemia (low count of healthy red blood cells).Iron deficiency anemia (IDA). Most people get all the iron they need from their diet. However, some may be prone to iron deficiency. Iron deficiency is the most common cause of anemia, occurring in 5% of women and 2% of men.

This article explains what iron does for your body and when iron supplements may be appropriate.

Dietary supplements are not regulated in the United States, which means that the Food and Drug Administration (FDA) does not approve them for safety and efficacy before the products are marketed. Whenever possible, choose a dietary supplement that has been tested by a trusted third party, such as USP, ConsumerLabs, or NSF. But even if supplements are third-party tested, that doesn't mean they're necessarily safe for everyone or universally effective. It is important to talk to your doctor about any supplements you are considering taking and to check for possible interactions with other supplements or medications.

Supplementary data

  • active ingredient: Ferro
  • Alternative name(r)(n): Ferrous Sulfate, Ferrous Gluconate, Ferrous Citrate, Ferrous Sulfate
  • recommended dose: The recommended daily dose varies from 7 to 27 milligrams per day, depending on age and sex, the upper tolerable limits are 40 to 45 milligrams per day, the treatment of iron deficiency anemia is 50 to 100 milligrams per day, divided in individual doses
  • Security Considerations: Discuss the correct dosage with a doctor before taking it. Avoid exceeding the tolerable upper iron limit unless recommended to treat iron deficiency, as iron poisoning has occurred in inadvertently in young children. Keep dietary supplements and adult medications out of the reach of children.

use of iron

The use of food supplements must be individualized and evaluated by a health professional such as a nutritionist, pharmacist or doctor. No dietary supplement is intended to treat, cure, or prevent any disease.

Iron supplementation is primarily intended to restore low iron levels. Iron deficiency treatment relieves symptoms that can occur with iron deficiency and anemia. It also helps prevent future complications when iron deficiency leads to anemia.

Iron supplementation is of no benefit in people with iron deficiencyiron deficiency.


Iron supplementation is useful forAnamiecaused by iron deficiency. There are several causes of anemia, but iron deficiency is the most common. Anemia occurs when iron deficiency progresses to the pointHemoglobin level (a protein in red blood cells)fall below the normal level.

If left untreated, iron deficiency can lead to abnormal heart rhythms, heart murmurs, an enlarged heart, and heart failure. Iron deficiency may also be associated with aincreased risk of fibromyalgia.

Iron supplementation can improve iron levels and treat ADI. Daily iron supplementation has been shown to reduce the prevalence of anemia and low iron levels in menstruating people.

Iron deficiency is the most common nutritional deficiency. If left untreated, it can lead to numerous health problems. If you suspect you have a deficiency, talk to your doctor so he can confirm it and treat it appropriately.


Iron can help control unexplained problemsfatigue, even in someone who is not anemic but has low ferritin levels (an indicator of iron stores). This is especially common in women during their reproductive years. Daily iron supplementation may reduce fatigue in menstruating women.

A randomized study looked at women ages 18 to 53 who reported experiencing fatigue. Women with less than 50 micrograms per liter (mcg/L) of ferritin and more than 12 grams per deciliter of hemoglobin were randomized to receive 80 milligrams (mg) of elemental iron or a placebo. The iron group reported a greater improvement in fatigue, but no improvement in overall quality of life.

Iron supplementation may improve fatigue in women with low ferritin levels.

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athletic performance

Iron is needed to make myoglobin, the protein that carries oxygen to muscles. Many athletes may have insufficient iron intake in their diet to support performance.

B. Athletes who do resistance training, such as marathons or endurance bike races, but may lose more iron. Also, being a woman or a vegetarian can put an athlete at higher risk of iron deficiency and anemia. Athletes must ensure that their diet contains enough iron to support peak performance.

Daily iron supplementation in menstruating people helped improve exercise performance in one study.It has also been shown to improve maximal and submaximal exercise performance in women of childbearing age.

Female athletes of reproductive age are at risk for iron deficiency, and iron supplementation has been shown to improve athletic performance in this group.

Restless Leg Syndrome

Restless Leg SyndromeIt is a health condition in which people have an uncontrollable urge to move their legs. This usually happens at night and can disrupt sleep.

A systematic review and meta-analysis published in 2019 concluded that iron supplementation is associated with an improvement in International Restless Legs Syndrome (IRLSS) scores at four weeks.


Research shows that cognitive levels decline withiron deficiency. In fact, concentration and alertness are affected almost immediately when iron levels in the blood drop. Restoring iron levels to a normal range can improve concentration and increase cognitive performance.

A double-blind, placebo-controlled study of adolescent girls who were not anemic but had low iron levels found that iron supplementation improved verbal learning and memory.A total of 81 participants enrolled in the study and were randomly assigned to receive 650 milligrams of oral iron supplementation twice daily or a placebo for eight weeks. Additionally, a review of 26 randomized controlled trials showed that iron supplementation in children with IDA improved hemoglobin levels and reduced deficits in cognitive and motor skills.

Iron: benefits, side effects, dosage and interactions (1)

iron deficiency

Iron deficiency is one of the most common nutritional deficiencies. Iron deficiency progresses in stages, leading to IDA:

The stages of iron deficiency are as follows:

  1. Iron stores in the body are depleted, resulting in low serum ferritin levels.
  2. The supply of iron available for red blood cell production is low, but blood hemoglobin levels remain normal.
  3. Iron stores are depleted, leading to anemia with small red blood cells and low levels of hemoglobin in the blood.

What causes iron deficiency?

Iron deficiency is caused by excessive iron losses or too little iron in the diet.

Losses can occur from blood loss, reduced absorption, or prolonged exercise (eg, athletes competing in marathon races or endurance bicycle races). For example, people who are menstruating are at increased risk of iron deficiency and ADH due to blood loss.And iron deficiency is usually more common during pregnancy due to the increased demands of a growing fetus.

People with disorders affecting the gastrointestinal (GI) tract or who have had a history of gastrointestinal surgery are at risk for IDA. For example, people with Crohn's disease or people who have had gastric bypass surgery (a type of weight-loss surgery) for obesity may be more likely to be iron deficient. This is because they may not be able to absorb adequate amounts of iron. Iron is absorbed in the duodenum and proximal jejunum (the first part of the small intestine through which digested food passes). Also, gastric surgery can reduce the production of stomach acid, which is necessary for the absorption of iron.

Following a vegetarian diet can lead to iron deficiency, since plant sources of iron are not absorbed as well as animal sources.

Risk groups for iron deficiency

Some people may be more prone to developing iron deficiency than others.

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The risk of developing iron deficiency is higher with:

  • people who are menstruating
  • people who are pregnant
  • Kinder
  • People who donate blood frequently.
  • People who have undergone gastric bypass surgery
  • Premature babies born before 37 weeks of gestation
  • Vegetarians and others who lack heme iron (the iron found in meat and seafood) in their diet

The incidence of iron deficiency is about 25% in people who have a Roux-en-Y gastric bypass and about 12% in people who have gastric sleeve surgery.

Iron deficiency also occurs in many health conditions, such as:

  • Krebs
  • Gastrointestinal disorders (eg, ulcerative colitis, Crohn's disease)
  • heart failure
  • Kidney disease during hemodialysis

Additionally, long-term use of antacids can also put you at higher risk.

How do I recognize an iron deficiency?

Iron deficiency symptoms include:

  • fatigue
  • difficulty breathing
  • dizziness
  • headache
  • pallor (pale skin)
  • Weak and brittle nails
  • difficult to focus
  • weak memory

If you suspect you are iron deficient, discuss your symptoms with your doctor. A complete blood count (CBC) includes a hematocrit and hemoglobin count. Low hemoglobin levels indicate anemia. Your doctor can perform additional tests to determine if iron deficiency is causing your anemia.

Aserum ferritin testIt is the preferred blood test to diagnose iron deficiency. You can detect low iron levels before going to IDA. In general, a serum ferritin level of less than 30 micrograms per liter (mcg/L) indicates iron deficiency, and a level of less than 10 micrograms per liter indicates ADI.

The World Health Organization (WHO) recently updated the recommended cut-off values ​​for indicating iron deficiency:

  • Children under 5 years: Less than 12 micrograms per liter
  • Children from 5 years and adults: less than 15 micrograms per liter
  • Children under 5 years of age with infection or inflammation: Less than 30 micrograms per liter
  • Children 5 years and older and adults with infection or inflammation: less than 70 micrograms per liter

What side effects does iron have?

Iron supplements can cause nausea, vomiting, and upset stomach.

I callis another very common side effect of iron supplementation.If you're constipated from iron supplements, make sure you're getting enough fiber and water in your diet. If it continues to be a problem, talk to your doctor about adding asoftener stoolIs it suitable for you.

The risk ofiron overloadDiet alone is minimal in most healthy adults. When there is more iron in the body than is needed, the body stores it primarily for future use.

However, people with certain genetic disorders are at risk of iron overload if their conditions cause them to absorb more iron from the diet.hemochromatosisIt is a genetic condition in which iron accumulates in the body. Iron supplementation is not recommended for hemochromatosis.

There are very rare cases of iron overdose leading to thisinternal bleeding,Seizure,To comeand even death.

The most common side effect of iron supplements is upset stomach and constipation. Getting enough fiber and water in your diet can help with constipation. Talk to your doctor about whether adding a stool softener is a good idea.


People with hemochromatosis should avoid iron supplements. With this disease, the iron in the body can reach dangerous levels.

Keep iron supplements out of the reach of children. There have been several fatal cases of accidental iron overdose in children. Iron supplements now come with a warning label to alert parents to this danger.

Dosage: How much iron should I take?

The recommended dietary allowance (RDA) for iron varies by age and gender:

  • babies from 7 to 12 months; 11mg/day
  • Children 1 to 13 years: 7 to 10 milligrams/day
  • Males 14 to 18 years: 11 milligrams/day
  • Women 14 to 18 years: 15 milligrams/day
  • Males 19 years and older: 8 milligrams/day
  • Women 19 to 50 years: 18 milligrams/day
  • Women 51 years and older (or when menopause is reached): 8 milligrams/day

During pregnancy, the requirement increases to 27 milligrams/day. For lactating mothers, the requirement is 9 to 10 milligrams/day.

(Video) Toxic Effects of Iron Overload – Dr. Berg on Iron Toxicity

The tolerable upper limit (TUL) for iron is:

  • Children under 13 years: 40 milligrams/day
  • Adolescents and adults: 45 milligrams/day

In general, healthy people who are not iron deficient should avoid supplements that provide more than the TUL of iron.

To treat iron deficiency, 50 to 100 milligrams of iron per day, divided into two or three doses, is often recommended. Follow your healthcare professional's guidelines for iron supplementation to treat a deficiency.

Iron supplements must be taken with food.Some claims suggest that taking iron with vitamin C may help with absorption. However, a recent study suggests that may not be the case. The study, which included people with iron deficiency, found no difference in laboratory values ​​(hemoglobin and serum ferritin) between those taking iron with vitamin C or iron alone.

Unless you are iron deficient, you should limit your total iron intake to no more than 45 milligrams per day. People with iron deficiency should discuss iron supplementation with their doctor.

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What happens if I take too much iron?

The risk of iron overload from diet alone is minimal.

Taking too much iron from supplements can cause an upset stomach and constipation. Excess iron can cause toxicity, inflammation of the stomach lining, and ulcers. The accumulation of iron in the body can eventually lead to cirrhosis, liver cancer, and heart disease. Taking iron supplements can also decrease zinc absorption.

In severe cases, iron overdose (60 mg/kg body weight) caused organ failure, coma, and death.

It is important to know that iron poisoning can occur in children and can cause serious injury or death. Iron poisoning can occur when young children accidentally swallow adult-grade iron capsules or tablets. To prevent this, keep dietary supplements out of the reach of children and store them in child-resistant containers. Contact a doctor if you think your child has taken adult iron tablets.


Iron supplements can interact with a number of medications, including:

  • Angiotensin Converting Enzyme (ACE)-Hemmer
  • carbamazepine, an anticonvulsant
  • levodopa, a drug used to treat Parkinson's disease
  • Levothyroxine, a thyroid medication
  • Penicillamine, a treatment for Wilson's disease and cystinuria
  • Quinolone-Antibiotics
  • Tetracycline-Antibiotika

Antacids reduce the acidity in the stomach necessary for the absorption of iron. Long-term use of antacids puts you at risk of developing iron deficiency.

Certain foods can decrease the body's absorption of iron, including:

  • black or green tea
  • Coffee shop
  • Owner
  • muesli
  • Violation
  • I am protein

Iron supplements can decrease the absorption of other important micronutrients, including zinc, copper, magnesium, and manganese. Calcium can interfere with iron absorption, so you should take iron and calcium supplements at different times of the day.

how to store iron

It is best to read labels to learn how to store iron, as there are many different forms of iron found in supplements. Keep all iron supplements out of the reach of children and pets.

frequent questions

  • What is the best way to achieve optimal iron levels?

    (Video) Best Iron Supplements - How To Supplement With Iron When You Don't Like Prescription Iron

    Diet. This minimizes the risk of overdose and ensures that you are getting other important nutrients as well.It is also important what you combine with iron. For example,footballlimits absorption. Chemical compounds called tannins, found in tea and coffee, also limit absorption.

  • Is it dangerous to take iron supplements if I am not anemic?

    Could be. Iron supplements are only recommended when a deficiency has been diagnosed or when there is a high risk of iron deficiency. Talk to your doctor to confirm the true cause of your symptoms and get advice on proper treatment.

Iron sources and what to look for

Iron is readily available in the diet. Iron in food comes in two different forms: heme and non-heme. Meat, poultry, and fish provide both heme and non-heme iron, while plant foods only provide non-heme sources of iron. Heme iron tends to be better absorbed.

Common dietary sources of heme iron are lean meat and seafood. Oysters, clams, clams, and sardines are also excellent sources of iron. Good sources of non-heme iron are beans, lentils, tofu, and green leafy vegetables (such as spinach).

In the United States, wheat and some other flours are fortified with iron. Breakfast cereals are also fortified with iron and can meet your iron needs self-sufficiently.

Breast milk contains enough iron for babies up to 6 months. After that, food intake provides additional iron. Infant formula is usually fortified with 12 milligrams of iron per liter.

Additionally, cooking in cast iron can also help you add more iron to your diet.

Preparation of requirements

Iron supplements come in many different forms, such as pills, gummies, chewable tablets, and liquids. There are also intravenous forms of iron that can be given under the supervision of a doctor.

It is important to note that most iron supplements contain iron as a compound, such as: B. iron sulfate, iron gluconate, or iron succinate. The amount of compound in the supplement is not the same as the amount of iron in the supplement. Ferrous sulfate, for example, consists of only 20% iron. Therefore, 250 milligrams of ferrous sulfate provide 50 milligrams of elemental iron. The supplement facts on the label should indicate the amount of elemental iron so you don't have to do any calculations.

A doctor can also give iron intravenously (into a vein). A single dose was more effective than oral supplementation in patients undergoing Roux-en-Y gastric bypass.


Iron is one of the most important minerals your body needs to stay healthy. If left untreated, iron deficiency can lead to anemia. Iron supplements are used to treat iron deficiency and ADH under medical supervision. There is almost no need for iron supplements unless you have iron deficiency or anemia.

When starting to take only iron supplements, avoid taking more than 45 milligrams per day (the TUL for iron) unless you are treating a deficiency or ADI.

The ideal iron supplement is one that provides the necessary dose with minimal side effects. In addition, it must be of high quality, absorb well, and be good value for money. Talk to your doctor before starting any new supplement.


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