SupplementGraded
All Ingredients
MineralsPregnancy Safe

Iron

Also known as: ferrous, ferric

Iron is essential for oxygen transport in blood (hemoglobin) and muscle (myoglobin). Iron deficiency is the most common nutritional deficiency worldwide. However, excess iron is toxic and supplementation should be based on documented need.

Key Benefits

  • Prevents and treats iron-deficiency anemia
  • Supports oxygen delivery to tissues
  • Essential for energy production
  • Supports immune function
  • Critical during pregnancy

Recommended Dosage

General Use
8-18 mg daily (varies by sex and age)
Upper Limit
45 mg daily
Pregnancy
27 mg daily

Forms & Bioavailability

Best Forms

  • Iron bisglycinate (gentle, well-absorbed)
  • Ferrous sulfate (effective but more GI issues)
  • Heme iron (from animal sources)

Forms to Avoid

  • Ferric forms (less bioavailable)
  • High-dose tablets without medical supervision

Safety Notes

  • Do NOT supplement unless deficiency is confirmed via blood test
  • Excess iron causes oxidative damage and organ toxicity
  • Men and postmenopausal women rarely need supplementation
  • Causes constipation and nausea in many people
  • Hereditary hemochromatosis makes iron supplementation dangerous

Drug Interactions

Consult your healthcare provider if you take any of the following:

Calcium (take separately)AntacidsTetracycline antibioticsZincCoffee and tea (reduce absorption)

Sources

  • WHO Guidelines on Iron Supplementation
  • NIH Office of Dietary Supplements

Top Iron Supplements