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Iron for women aged 19 to 50

Sixteen milligrams a day — the highest adult figure in the EFSA table, and 45 per cent more than an adult man needs. Menstrual loss is the whole reason, and it is also why the number drops back the moment periods stop.

EFSA note on this row: premenopausal, for menstrual losses

These are published population reference values, not a diagnosis and not a prescription. A reference intake describes what covers a healthy group; it cannot tell you your own status, and no page can. Pregnancy, chronic illness, medicines and malabsorption all change the picture — take those questions to a doctor, midwife, pharmacist or dietitian.

Why this group has the highest requirement of anyone

Iron is recycled so efficiently that basal daily losses are small. What makes the premenopausal female figure the highest adult value in the table is menstruation, and specifically the shape of its distribution. Most women lose a moderate amount of iron each month; a minority lose several times more. A Population Reference Intake has to cover almost everyone, so it is pulled upward by that tail.

The practical consequence: 16 mg is not what the average woman in this group needs. It is the amount that covers about 95 per cent of them. If your periods are light, your own requirement is lower; if they are heavy, 16 mg may not be enough, and heavy menstrual bleeding is itself a reason to see a doctor rather than to buy a bigger supplement.

Sixteen milligrams is genuinely hard from food alone

This is the main honest finding of this page. Look at the table below and count the portions: reaching 16 mg a day from ordinary food takes deliberate effort, and it takes more effort on a diet without red meat, because plant iron is absorbed far less efficiently.

The techniques that work are about absorption rather than quantity. Put a vitamin C source in the same meal as the beans, lentils, wholegrain rye or pumpkin seeds — a pepper, a tomato, a citrus fruit. Move tea and coffee away from the meal itself, because their polyphenols bind iron in the gut. Keep a large calcium dose, such as a supplement or a big glass of milk, out of the iron-heavy meal.

Tiredness is not a diagnosis

Iron deficiency does cause fatigue, and it is common in this group. So do sleep debt, thyroid disease, depression, coeliac disease, pregnancy and a dozen other things, and iron supplements taken on a hunch can delay finding the real cause. Iron overload is also a real condition, and iron tablets are one of the commonest causes of serious accidental poisoning in small children.

The right order is: symptoms, then a blood test for ferritin and haemoglobin, then a decision. A clinician can do that in one visit. This page can tell you what the reference intake is; it cannot tell you your iron status.

How this compares with every other group

Ordinary food against the 16 mg figure for women 19-50

Top of this list: Soybeans, 7.71 mg in a 150 g serving (a portion, cooked) — 48% of the 16 mg figure for women 19-50. It would take about 3 of those to cover a full day from that one food, which is why a real diet spreads it across several rows.

Portion sizes are ordinary household servings chosen for this table, not official reference portions, and the shortlist is an editorial one: everyday foods eaten in this region rather than the highest per-100 g entries in the database. A raw per-100 g ranking would be topped by dried herbs, drink powders and fortified breakfast cereals, which answers a different question. The composition data is American, so where US fortification practice differs from European practice the row carries a dagger and the reason. For the full per-100 g ranking of a nutrient, the food-data section of this site publishes one.

The whole nutrient, not just this group

The Iron reference intake page carries the full age and sex table, the upper level, and what the value type means.

Related pages

Sources: EFSA Dietary Reference Values · Regulation (EU) No 1169/2011, Annex XIII · USDA FoodData Central SR Legacy (food composition) · EFSA scientific opinion on dietary reference values for iron (2015) · Regulation (EU) No 1169/2011, Annex XIII · checked 2026-09-06

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