Safe Recommended Iron Intake
The safe recommended daily iron intake for enteral nutrition is 18-30 mg per day, while parenteral nutrition should provide at least 1 mg/day of elemental iron. 1
Recommended Daily Iron Intake by Population
Iron requirements vary significantly based on age, sex, and physiological state:
- Adult men and postmenopausal women: 8-8.7 mg/day 1
- Women of reproductive age: 14.8-18 mg/day 1
- Adolescent girls: 15 mg/day 1
- Pregnant women: 30 mg/day (preventive) or 60-120 mg/day (treatment) 2
- Athletes with risk factors for deficiency: Higher intake recommended, with female soldiers advised to consume at least 22 mg/day 1
Iron Status Assessment
Iron status should be evaluated in the following situations:
- Anemia
- Persistent major fatigue
- Suspected iron deficiency or overload 1
A comprehensive iron status evaluation should include:
- Plasma iron
- Transferrin
- Transferrin saturation
- Ferritin
- CRP
- Hepcidin
- Red blood cell morphology 1
Interpretation of Iron Status
| Ferritin Level | Interpretation |
|---|---|
| <30 μg/L | Definitive iron deficiency |
| 30-100 μg/L with transferrin saturation <20% | Possible iron deficiency, especially with inflammation |
| >100 μg/L with normal transferrin saturation | Iron deficiency unlikely [2] |
Iron Supplementation Guidelines
Oral Iron Supplementation
When iron deficiency is identified, oral supplementation is typically the first-line treatment:
- Standard dose: 60-120 mg elemental iron daily 2
- Formulation: Ferrous sulfate (65 mg elemental iron per 324 mg tablet) is commonly used 3
- Timing: Morning doses are preferred to maximize absorption 4
- Frequency: Alternate-day dosing may improve absorption and reduce side effects 4
- Duration: Continue for 3 months after hemoglobin normalization to replenish iron stores 2
Intravenous Iron Administration
IV iron should be considered when:
- Oral iron is not tolerated
- Absorption is impaired
- Rapid correction is needed (hemoglobin <10 g/dL)
- Iron deficiency is confirmed with low hepcidin levels in critically ill patients 1, 2
For correction of iron deficiency: A single IV dose of 1 g iron using carbohydrate products is recommended 1
Special Considerations
Athletes and Active Individuals
Athletes, particularly females, are at higher risk of iron deficiency due to:
- Restrictive diets (vegetarian/vegan)
- High-impact activities with repetitive ground strikes
- Endurance training causing erythrocyte damage
- Heavy menstrual bleeding 1
Iron Absorption Enhancers and Inhibitors
- Enhancers: Vitamin C, heme iron (meat, poultry, fish)
- Inhibitors: Polyphenols (certain vegetables), tannins (tea), phytates (bran), calcium (dairy products) 1
Iron Overload Conditions
In hemochromatosis and iron overload conditions, iron stores should be reduced by repeated venesection 1. Normal total body iron stores are approximately:
- 2.2-3.5 g in healthy women
- 3-4 g in men 1
Monitoring Response to Treatment
- Check hemoglobin response at 2-4 weeks (expect ≥10 g/L rise within 2 weeks)
- Monitor every 3 months for 12 months, then every 6 months for 2-3 years 2
Iron supplementation should be tailored based on individual needs, with careful monitoring to avoid both deficiency and overload states.