Supplement Scholar
Mineral

Iron

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Iron. Oxygen-carrying mineral central to hemoglobin and cellular respiration.

How it works. Hemoglobin/myoglobin oxygen binding; cofactor for cytochromes and many enzymes.

What the research supports. 2 graded claims. Strongest: Resolves iron-deficiency anemia (strong).

How much to take. Typical dose: 18 mg female / 8 mg male; 65 mg elemental for anemia. Alternate-day dosing increases absorption.

Side effects and interactions. 3 medication interactions listed. Serious: Toxic overdose (esp. children).

Stacking. Pairs well with Vitamin C. Avoid combining with Calcium / coffee / tea, Hemochromatosis.

Forms. 3 forms. Pick one to open its profile.

Key studies. 9 studies cited. The strongest are listed with links to PubMed.

Community. Experiences from people who have tried Iron. Anecdotes are not medical advice.

Iron. Oxygen-carrying mineral central to hemoglobin and cellular respiration.

Element Fe · Z = 26Fe · 55.84 g/mol

What it is

Oxygen-carrying mineral central to hemoglobin and cellular respiration.

Also called

Ferrous bisglycinateFerrous sulfate

Food sources

Red meatLiverLentilsSpinach

Goals

Energy ProductionWomen's HealthGeneral Wellness

How it works

Hemoglobin/myoglobin oxygen binding; cofactor for cytochromes and many enzymes.

Pathways

  • Oxygen transport
  • ETC cytochromes

Effects

  • +Hemoglobin synthesis supports
  • +Energy in iron-deficient supports

What the research supports

Resolves iron-deficiency anemiastrong
Improves fatigue in low-ferritin womenmoderate

Strong: consistent results across large trials or meta-analyses. Moderate: several trials, mostly positive. Limited: small or mixed studies. Preclinical: animal or cell research only.

Typical dose
18 mg female / 8 mg male; 65 mg elemental for anemia
TimingAlternate-day dosing increases absorption
With foodEither with or without food.
Best formMost evidence is based on the bisglycinate (gentle) form.
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Side effects & interactions

Common side effects

  • Constipation
  • Nausea
  • Black stools

Serious

  • Toxic overdose (esp. children)
  • Hemochromatosis worsening

Medication interactions

PPIsmoderate

Reduce absorption.

Levothyroxinemoderate

Separate 4 h.

Quinolonesmoderate

Chelates antibiotic.

Check any supplement–medication combination with your pharmacist before starting.

Combines with

Pairs well

Avoid combining

  • Calcium / coffee / teaReduce iron absorption.
  • HemochromatosisIron overload risk.

Key studies

9 studies cited in total.

PubMed: Iron — Resolves iron-deficiency anemia ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching Iron and "Resolves iron-deficiency anemia". Filter by RCT, meta-analysis, or year on the results page.

PubMed: Iron — Improves fatigue in low-ferritin women ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching Iron and "Improves fatigue in low-ferritin women". Filter by RCT, meta-analysis, or year on the results page.

PubMed: Iron — randomized controlled trial ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching Iron and "randomized controlled trial". Filter by RCT, meta-analysis, or year on the results page.

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