From the Guidelines
The body should absorb about 1-3 mg of iron per day to maintain iron balance, with adult men and post-menopausal women requiring around 1 mg/day and pre-menopausal women needing about 2 mg/day. This recommendation is based on the most recent and highest quality study available, which suggests that the estimated requirement for maintenance of iron status is 1 mg/day for adult men and post-menopausal women, and about 2 mg per day for pre-menopausal women 1.
The Dietary Reference Intake (DRI) for iron varies according to stages of life and gender, with adult men and post-menopausal females requiring 8 mg/day, of which 1 mg/day is absorbed 1. It's essential to note that iron absorption can be enhanced by consuming vitamin C-rich foods alongside iron sources, while calcium, tannins in tea, and phytates in some plant foods can inhibit absorption.
Key points to consider:
- Iron requirements vary by age, sex, and life stage
- Adult men and post-menopausal women require about 1 mg/day of absorbed iron
- Pre-menopausal women need about 2 mg/day of absorbed iron
- Iron absorption can be influenced by dietary factors, such as vitamin C and calcium intake
- Exceeding recommended amounts without medical supervision can lead to iron accumulation in organs and cause damage 1.
In clinical practice, it's crucial to consider individual patient needs and monitor their response to iron supplementation to ensure optimal iron balance and minimize potential adverse effects.
From the Research
Iron Absorption Requirements
The daily iron absorption requirements for the human body are not explicitly stated in the provided studies. However, the studies discuss various forms of iron supplementation and their effects on iron deficiency anemia.
Forms of Iron Supplementation
- Oral iron supplements, such as ferrous sulfate, are commonly used to treat iron deficiency anemia 2
- Intravenous iron supplements, such as sodium ferric gluconate complex in sucrose, are used to treat iron deficiency anemia in patients with severe iron deficiency or those who cannot tolerate oral iron supplements 3, 4, 5, 6
- Lactoferrin, a milk-derived iron-binding glycoprotein, has been shown to have a positive effect on iron metabolism and may be a suitable alternative to ferrous sulfate supplementation 2
Effects of Iron Supplementation
- Oral iron supplements can increase hemoglobin and ferritin levels, but may have gastrointestinal side effects 3, 2
- Intravenous iron supplements can rapidly increase iron stores and improve hemoglobin levels, but may have a higher risk of adverse reactions 3, 4, 5, 6
- Lactoferrin supplementation has been shown to have a positive effect on serum iron, ferritin, and hemoglobin levels, with fewer side effects compared to ferrous sulfate 2
Safety Profiles of Iron Supplements
- Sodium ferric gluconate complex in sucrose has been shown to have a safer profile compared to iron dextran, with a lower risk of severe adverse reactions 4, 5, 6
- Ferric gluconate has been associated with a slightly decreased risk of infection-related outcomes compared to iron sucrose in patients with a hemodialysis catheter 5