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Iron

An essential dietary trace mineral critical for oxygen transport, mitochondrial energy production, and cellular respiration.

Evidence-Based
Fact-Checked
Updated: Sep 20, 2026
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Clinical Profile

Quick Reference

Scientific Rating
5.0
/ 5.0
Standardized Form
Ferrous Bisglycinate (Chelated Iron), Ferrous Sulfate, or Ferrous Gluconate

Iron is a foundational mineral that functions as a core component of hemoglobin and myoglobin, facilitating the transport and storage of oxygen throughout the body. Beyond oxygen delivery, iron is a critical enzymatic cofactor in the mitochondrial electron transport chain (via cytochromes). This means that cellular ATP (energy) production is severely impaired in states of iron deficiency, which explains the profound clinical fatigue associated with depleted ferritin stores. In dietary supplements, it is provided in various molecular forms, with chelated versions offering vastly superior gastrointestinal tolerability.

Clinical Summary

Universally recognized and clinically prescribed for the prevention and treatment of iron deficiency anemia. Well-documented to reverse chronic fatigue, cognitive impairment, and physical weakness when those symptoms are driven by depleted systemic iron stores.

Dosage Guidelines

18mg for baseline adult female health; 65mg to 130mg (elemental iron) daily for clinical deficiency, optimally taken with Vitamin C to enhance absorption.

Safety & Side Effects

Non-chelated forms (like Ferrous Sulfate) commonly cause severe constipation, nausea, dark stools, and abdominal cramping. Chelated forms significantly reduce these issues.

Known Interactions

Decreases absorption of certain antibiotics (tetracyclines) and thyroid medications (levothyroxine). Calcium, tannins (coffee/tea), and phytates strongly inhibit iron absorption.

Scientific References

Medical Disclaimer

The information provided in this clinical review is for educational and informational purposes only. It is not intended to be a substitute for professional medical advice, diagnosis, or treatment.

*These statements have not been evaluated by the Food and Drug Administration (FDA). This product or ingredient is not intended to diagnose, treat, cure, or prevent any disease.

Always consult your physician or other qualified health provider with any questions you may have regarding a medical condition, or before beginning any new diet, fitness, supplement, or treatment regimen, especially if you have pre-existing medical conditions or are taking prescribed medications.

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