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Strong human evidenceEssential mineral / oxygen transport

Iron

Iron helps blood carry oxygen and supports muscle and cellular metabolism. Low energy is not proof of iron deficiency, and unnecessary iron can be harmful.

Also indexed as: Ferrous sulfate · Ferrous bisglycinate · Heme iron · Fe

A clear starting point

Iron helps blood carry oxygen and supports muscle and cellular metabolism. Low energy is not proof of iron deficiency, and unnecessary iron can be harmful.

Systems mapping shows biological relevance, not a treatment recommendation or a patient CPI score.

Molecular formula: Fe

No validated chemical structure is displayed in this edition.

How it works

Oxygen transport / cellular energy metabolism

Iron helps blood carry oxygen and supports muscle and cellular metabolism. Low energy is not proof of iron deficiency, and unnecessary iron can be harmful.

Targets & processes
Hemoglobin, myoglobin and iron-containing metabolic proteins.
Systems & tissues
Red blood cells, muscle and oxidative-metabolism systems.

What does the evidence show?

Iron replacement can correct confirmed iron deficiency and iron-deficiency anemia. It is not a general performance supplement for iron-replete people.

What this does not establish

Cause of deficiency matters; simply replacing iron can miss ongoing blood loss or malabsorption.

NIH ODS: Iron — Health Professional Fact Sheet

Official educational / regulatory source · Official educational source

Iron replacement can correct confirmed iron deficiency and iron-deficiency anemia. It is not a general performance supplement for iron-replete people.

Limitations: Cause of deficiency matters; simply replacing iron can miss ongoing blood loss or malabsorption.

Citation metadata from PubMed, a service of the U.S. National Library of Medicine, NIH. A citation match is not a guarantee of study quality. Abstracts are not full-text reviews.

Safety is a separate question

Constipation, nausea and abdominal discomfort are common with supplements. Acute overdose can be life-threatening, particularly in children.

Contraindications & cautions

Hemochromatosis/iron overload and anemia without confirmed iron deficiency require assessment. Keep iron products safely away from children.

Medication & supplement interactions

Iron can reduce absorption of levothyroxine and levodopa; acid-suppressing medicines can affect iron absorption.

Regulatory status · United States

United States: dietary-supplement status is product-specific, not FDA approval of disease treatment. Food, supplement and drug formulations must not be assumed interchangeable.

Read the official source

This is not an exhaustive safety list. Regulatory status varies by jurisdiction and product; investigational use is not approval.

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Education, not a prescription. Research summaries are not medical advice, dosing instructions, or an offer to sell. Mechanistic findings do not establish clinical effectiveness. US regulatory status is product- and indication-specific and may change. Discuss health decisions with a licensed clinician.