Iron
What it is and what it does
- Iron is a mineral the body needs for growth and development. (NIH Office of Dietary Supplements. Iron Fact Sheet for Consumers (updated 2023-08-17))
- An adult body holds about 3 to 4 g of iron, most of it in haemoglobin. (NIH Office of Dietary Supplements. Iron Fact Sheet for Health Professionals (updated 2025-09-04))
- Iron is used to make haemoglobin, the protein in red blood cells that carries oxygen from the lungs to all parts of the body. (NIH Office of Dietary Supplements. Iron Fact Sheet for Consumers (updated 2023-08-17))
- Iron is also part of myoglobin, a protein that supplies oxygen to muscles. (NIH Office of Dietary Supplements. Iron Fact Sheet for Consumers (updated 2023-08-17))
- Iron is needed for physical growth, brain and nerve development, cell functioning and making some hormones. (NIH Office of Dietary Supplements. Iron Fact Sheet for Health Professionals (updated 2025-09-04))
- ICMR-NIN: iron is necessary for forming haemoglobin, the red pigment of red blood cells, which carries oxygen to the tissues. (ICMR-NIN. Dietary Guidelines for Indians 2024)
Why it matters
- When the body's iron stores run low, iron-deficiency anaemia develops: red blood cells become smaller and carry less oxygen. (NIH Office of Dietary Supplements. Iron Fact Sheet for Consumers (updated 2023-08-17))
- Symptoms of iron-deficiency anaemia include weakness, tiredness, lack of energy and problems with concentration and memory. (NIH Office of Dietary Supplements. Iron Fact Sheet for Consumers (updated 2023-08-17))
- WHO considers iron deficiency, mainly from too little dietary iron, the most common nutritional deficiency leading to anaemia. (WHO fact sheet: Anaemia (10 February 2025))
- Iron deficiency in pregnancy raises maternal mortality and may lower birth weight. (ICMR-NIN. Dietary Guidelines for Indians 2024)
- In children, iron deficiency increases susceptibility to infections and impairs learning ability. (ICMR-NIN. Dietary Guidelines for Indians 2024)
- Too much: high-dose iron supplements can cause stomach upset, constipation, nausea, abdominal pain, vomiting and diarrhoea. (NIH Office of Dietary Supplements. Iron Fact Sheet for Consumers (updated 2023-08-17))
- Accidental overdose of iron products is a leading cause of fatal poisoning in children under 6. (NIH Office of Dietary Supplements. Iron Fact Sheet for Consumers (updated 2023-08-17))
- An inherited condition, haemochromatosis, causes iron to build up to toxic levels. (NIH Office of Dietary Supplements. Iron Fact Sheet for Consumers (updated 2023-08-17))
General information, not medical advice — for your own needs, ask a doctor or dietitian.
How much is needed
| Who | Amount | What the figure is | Whose figure |
|---|---|---|---|
| Adult man, sedentary work | 19 mg/day | recommended dietary allowance | ICMR-NIN 2020 |
| Adult woman, sedentary work | 29 mg/day | recommended dietary allowance | ICMR-NIN 2020 |
| Pregnant woman | 27 mg/day | recommended dietary allowance | ICMR-NIN 2020 |
| Adult men and women (and pregnancy where stated) | 45 mg/day | safe upper limit | ICMR-NIN 2020 |
Sources: ICMR-NIN Nutrient Requirements for Indians 2020, as given by FSSAI (Direction of 2 Aug 2021); ICMR-NIN Nutrient Requirements for Indians 2020 (Short Report)
In every millet and pseudo-cereal, per 100 g raw
| Grain | Amount | Source |
|---|---|---|
| Fonio | 29.4 mg | FAO WAFCT 2019 |
| Rajgira (amaranth) | 8.02 mg | IFCT A002 |
| Teff | 7.63 mg | USDA FDC 169747 |
| Quinoa | 7.51 mg | IFCT A009 |
| Bajra (pearl millet) | 6.42 mg | IFCT A003 |
| Barnyard millet | 5 mg | NIN 2007 via ICAR-IIMR |
| Ragi (finger millet) | 4.62 mg | IFCT A010 |
| Jowar (sorghum) | 3.95 mg | IFCT A005 |
| Proso millet | 3.01 mg | USDA FDC 169702 |
| Foxtail millet | 2.8 mg | NIN 2007 via ICAR-IIMR |
| Kodo millet | 2.34 mg | IFCT A017 |
| Kuttu (buckwheat) | 2.2 mg | USDA FDC 170286 |
| Little millet | 1.26 mg | IFCT A016 |
Each grain has ONE source, named on its page: IFCT = Indian Food Composition Tables 2017 (ICMR-NIN) with its food code; USDA FDC; FAO WAFCT 2019; NIN 2007 via ICAR-IIMR. Values exactly as printed, not converted — tables differ in method, so compare within a source. Published values for the grain, not a laboratory test of our packs.
Absorption and food
- Vitamin C-rich fruits such as guava, pineapple, lemon and orange improve iron absorption from plant foods. (ICMR-NIN. Dietary Guidelines for Indians 2024)
- ICMR-NIN recommends at least 20 mg of vitamin C per 1000 kcal of the diet to improve iron absorption. (ICMR-NIN Expert Group. Short Report of Nutrient Requirements for Indians: Recommended Dietary Allowances and Estimated Average Requirements - 2020)
- Phytate (in grains and beans) and some polyphenols reduce non-haem iron absorption. (NIH Office of Dietary Supplements. Iron Fact Sheet for Health Professionals (updated 2025-09-04))
- Calcium may reduce absorption of both haem and non-haem iron. (NIH Office of Dietary Supplements. Iron Fact Sheet for Health Professionals (updated 2025-09-04))
- Tannins in tea and coffee interfere with iron absorption; ICMR-NIN advises avoiding tea and coffee for at least one hour before and after meals. (ICMR-NIN. Dietary Guidelines for Indians 2024)
- Fermenting and sprouting grains, and eating vitamin C-rich foods, improve iron availability. (ICMR-NIN. Dietary Guidelines for Indians 2024)
- Phytic acid in cereals and pulses hinders mineral absorption; boiling or pressure-cooking lowers it considerably, making iron, calcium, magnesium and zinc more absorbable. (ICMR-NIN. Dietary Guidelines for Indians 2024)