Mineral
Iron
Also known as: Fe, Iron ion, Ferrous, Ferric
Essential for oxygen transport and immune cell function, but excess can feed pathogens. Important to test before supplementing.
Primary uses
- Hair loss
- Hair growth
- Ferritin support
- Energy
- Oxygen transport
- Fatigue
- Anemia prevention
- Immune cell function
- Anemia treatment
- Immune function
- Cognitive function
How it works
- Hemoglobin component
- Myoglobin in muscles
- Electron transport chain
- Enzyme cofactor
Dosage
- Typical range
- 18-45mg daily when deficient
- Timing
- Empty stomach or with vitamin C
- With food
- Optional, may reduce absorption
- Duration
- Until levels normalize
- Special populations
- Women, vegetarians
Forms
- Bisglycinate
- Ferrous sulfate
- Heme iron
- Iron bisglycinate
- Heme iron polypeptide
Safety
Common side effects
- Constipation
- Nausea
- Dark stools
Contraindications
- Hemochromatosis
- Iron overload
Known interactions
- Cautionwith zinc
Zinc and iron compete for absorption
- Warningwith calcium
Calcium significantly reduces iron absorption
- Synergywith vitamin c
Vitamin C dramatically enhances iron absorption
- Cautionwith antacids
Antacids significantly reduce iron absorption
- Warningwith thyroid medication
Iron reduces levothyroxine absorption
- Synergywith vitamin a
Vitamin A enhances iron absorption
Evidence notes
Essential mineral critical for oxygen transport
Grade A: Multiple well-designed human trials support the main claims.
Related in Mineral
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Open the checkerMedical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider.