What does iron do in the body?

Iron is needed to make hemoglobin, which carries oxygen in red blood cells. It also supports energy metabolism and normal immune function.

What are common signs of iron deficiency?

Iron deficiency can cause fatigue, weakness, pale skin, shortness of breath with exertion, and reduced exercise tolerance. Only blood tests can confirm deficiency.

How much iron should I take as a supplement?

Supplement needs vary by age, sex, diet, and lab results. Many adults meet needs with diet, while deficiency may require higher doses under medical guidance.

Which foods are high in iron, and how can I absorb it better?

Heme iron from meat and seafood is generally absorbed better than non-heme iron from beans, lentils, tofu, spinach, and fortified grains. Vitamin C-rich foods can improve non-heme iron absorption, while tea or coffee with meals may reduce it.

Can you take too much iron?

Yes—excess iron can cause gastrointestinal side effects and can be harmful, especially in people with iron overload conditions. Avoid high-dose iron unless advised by a clinician and keep supplements away from children.

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Vitamin B

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Trimethylglycine (Betaine)

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Iron

Strong study situation·10/10

A higher score indicates better study conditions, but not necessarily effectiveness.

Iron is an essential mineral crucial for oxygen transport, energy production, and the prevention of anemia.

Cognitive Enhancement Essential Nutrient Immune Booster Anemia Support Energy Support

dose range

8–60 mg

1-3 divided doses per day if using higher amounts for deficiency.

Consumption

Take on an empty stomach for best absorption. If GI discomfort occurs, may take with food.

Not fat-soluble.

Best time

Best taken in the morning or with the first meal. Vitamin C enhances absorption; avoid taking with calcium or antacids.

Description

Iron is a vital nutrient required for the synthesis of hemoglobin in red blood cells, supporting the delivery of oxygen throughout the body and overall metabolism. Iron deficiency is a leading cause of anemia worldwide, particularly affecting women and children.

benefits

Main effects with level of evidence

Strong

Note on evidence

Iron’s role in preventing and treating anemia is well-established, and its importance for systemic health has robust clinical support.

Prevents and treats iron deficiency anemia

Strong

Iron supplementation effectively corrects iron deficiency anemia, which can cause fatigue, weakness, and pallor by restoring hemoglobin levels.

Particularly relevant for: Individuals with iron-deficiency anemia · Pregnant women · Women of reproductive age · Children · +2

BMJ2003 · British Medical Journal NIHODS2021 · National Institutes of Health (ODS): Iron Fact Sheet WHOIron2016 · World Health Organization: Guideline on daily iron supplementation in adult women and adolescent girls UpToDateIron2023 · UpToDate: Causes and diagnosis of iron deficiency and iron deficiency anemia in adults

Supports energy production and physical performance

Moderate

Iron facilitates oxygen delivery and is vital in cellular respiration and ATP production, enhancing energy and physical performance. Deficiency may impair endurance and exercise capacity.

Particularly relevant for: Athletes · General population · Pregnant women · Older adults

NIHODS2021 · National Institutes of Health (ODS): Iron Fact Sheet EFSA2015 · European Food Safety Authority: Scientific Opinion on Dietary Reference Values for Iron

Improves cognitive function (in deficiency)

Moderate

Iron is important for brain development and neurotransmitter synthesis; supplementation in deficient individuals improves learning, memory, and attention.

Particularly relevant for: Children · Pregnant women · Individuals with iron deficiency

PEDIATRICS2007 · Pediatrics NIHODS2021 · National Institutes of Health (ODS): Iron Fact Sheet

Supports immune function

Limited

Iron is necessary for proliferation and function of immune cells, contributing to normal immune response.

Particularly relevant for: Children · Immunocompromised individuals · Those with iron deficiency

NIHODS2021 · National Institutes of Health (ODS): Iron Fact Sheet

Safety & Information

Important safety information & known risks

For educational purposes only • not medical advice

Generally safe when used as directed, but excessive intakes pose health risks.

warning notices

GI side effects (nausea, constipation) are common, especially at higher doses.
Iron overload can occur with excessive, chronic supplementation—greater risk in those with hereditary hemochromatosis.
Iron supplements are a leading cause of accidental poisoning in children—store safely out of reach.
Monitor blood markers when supplementing long-term or in high doses.

Known interactions with medications

Antibiotics (fluoroquinolones, tetracyclines)
Antacids
Proton pump inhibitors

Contraindications / special precautions

Hemochromatosis or other iron overload disorders
Known hypersensitivity to iron products

interactions

Important interactions between active ingredient ↔ supplement / medication / food

Iron absorption is influenced by other nutrients, supplements, and drugs. Notable interactions exist with calcium, vitamin C, some antibiotics, and food compounds such as tannins.