What to know first
- Adult women ages 19–50 generally need 18 mg daily; pregnancy raises the recommended amount to 27 mg.
- Plant-based iron is absorbed less efficiently than heme iron.
- High-dose iron can cause side effects and should not be taken casually.
Understand changing needs
NIH ODS lists 18 mg daily for adult women ages 19 to 50, 27 mg during pregnancy, 9 mg during breastfeeding, and 8 mg for adults 51 and older. Heavy menstrual bleeding can raise deficiency risk, while iron needs after menopause are usually lower.
Heme iron from animal foods is absorbed more readily than nonheme iron from plants. Vitamin C-rich foods can improve absorption of plant iron.
Test before treating
Fatigue, weakness, shortness of breath, and hair changes are not specific to iron deficiency. Blood testing can assess anemia and iron stores while a clinician looks for causes such as blood loss or absorption problems.
High-dose supplements commonly cause nausea or constipation and can interact with medicines. Keep iron away from children because overdose can be fatal.
Sources and further reading
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