What iron actually does in your body, from spinach to blood

Iron's best-known job is in haemoglobin, which carries oxygen in red blood cells. A few useful things to know:

1. Plant foods like spinach and lentils contain non-heme iron; meat contains heme iron, which the body absorbs more easily.

2. Vitamin C eaten at the same meal can help absorb non-heme iron.

3. Tea and coffee with a meal can reduce absorption.

4. Needs differ by age and sex, and too much iron can also be harmful.

5. A blood test, not a guess, tells you if you're low. Ask a clinician before supplementing.

Body Unpacked shows what 44 everyday foods contain and where their nutrients act in the body, with values from USDA FoodData Central. Nutrient Journeys follow 14 nutrients on an animated body map, and Evidence Lens labels the kind of evidence behind 23 popular health statements. 249 sourced topics. No account, no ads, works offline.

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