II. Physiology: Iron
- Total Body Iron
- Men: 50 mg/kg (or 3.8 grams for 75 kg man)
- Women: 42 mg/kg (or 2.3 grams for 55 kg woman)
- Normal adult iron distribution
- Functional iron (70%)
- Hemoglobin component (80%)
- Myoglobin
- Intracellular respiratory enzymes (Cytochrome P450)
- Storage or transport iron (30%)
- Ferritin (primary storage)
- Hemosiderin
- Transferrin (iron transport)
- Functional iron (70%)
- Iron Loss
- Men and non-menstruating women: 1 mg iron/day
- Menstruating women: 1.6 to 2.5% more per day
- Blood loss varies widely per Menstrual Cycle
- Average loss: 10 mg iron/cycle
- Blood loss may approach 42 mg/cycle in heavy flow
- Pregnancy: 700 mg iron lost
- Whole blood donation (500 cc): 250 mg iron lost