Vitamin C and Infant Iron Supplementation
Vitamin C is NOT required when giving infant iron supplements, and adding ascorbic acid does not improve ferrous iron absorption in therapeutic supplementation. 1
Key Recommendation
Do not add ascorbic acid to ferrous sulfate iron supplements in infants and children. Despite being more expensive, it provides no additional benefit for absorption of ferrous iron used in therapeutic supplementation. 1
When Vitamin C IS Beneficial (Dietary Context)
Vitamin C plays an important role in dietary iron absorption from food sources, not therapeutic iron supplements:
For Infants 4-12 Months
- Include vitamin C-rich foods (fruits, vegetables, or juices) with meals to enhance absorption of non-heme iron from complementary foods. 1, 2
- This is particularly important when introducing iron-fortified cereals and plant-based iron sources at 4-6 months of age. 3
- Vitamin C-rich foods should be offered with at least one meal daily to maximize dietary iron uptake. 3
For Children 1-5 Years
- Continue offering vitamin C sources with meals to improve absorption of dietary non-heme iron from foods. 2, 3
- This strategy is most effective for iron from vegetables, fortified cereals, and other plant-based sources where absorption is typically less than 10%. 4
Therapeutic Iron Supplementation Protocol
When treating iron deficiency anemia with oral iron supplements:
- Administer 3 mg/kg/day of elemental iron (ferrous sulfate) between meals for maximum absorption. 1, 2
- Give iron 2 hours before or 1 hour after meals to avoid food interference with absorption. 1
- Do not co-administer vitamin C supplements with therapeutic iron drops or tablets. 1
- Continue treatment for 2-3 months after hemoglobin normalization to replenish iron stores. 1, 2
Important Distinctions
The enhancement effect of vitamin C differs significantly based on context:
- Dietary iron from foods: Vitamin C enhances absorption of non-heme iron from plant sources, particularly in meals containing inhibitors like phytates and tannins. 4, 5, 6
- Therapeutic ferrous sulfate supplements: Ascorbic acid does not improve absorption and should not be added. 1
- The molar ratio needed for dietary enhancement (2:1 to 4:1 vitamin C to iron) would be impractical and unnecessary for therapeutic supplementation. 5
Critical Pitfalls to Avoid
- Do not use vitamin C supplements in iron-overloaded patients (hemochromatosis, thalassemia), as high-dose vitamin C can mobilize iron from stores and potentially cause cardiac deterioration. 4
- Avoid supplemental vitamin C exceeding 500 mg daily in any patient with elevated iron stores, especially before iron depletion is achieved. 4
- Do not assume dietary vitamin C recommendations apply to therapeutic iron supplementation - these are distinct clinical scenarios with different absorption mechanisms. 1