Reviewed against NHS, ACOG, and peer-reviewed clinical guidance.
Women aged 19 to 49 need 14.8mg of iron a day, almost twice the 8.7mg for men, because periods lose iron. Heavy periods raise the risk of running low.
Women having periods need more iron than men, and the NHS sets 14.8mg a day for women aged 19 to 49, almost twice the 8.7mg for men, because periods lose iron. Daily intake across the whole month matters more than extra iron on bleeding days, and heavy periods raise the risk of running low.
This article draws on NHS iron guidance, a 2025 review of iron deficiency in JAMA, a 2023 randomised trial of iron tablets in eClinicalMedicine, and the NICE guideline on heavy menstrual bleeding, current as of November 2026.
Why Do Periods Increase Your Iron Needs?
Periods increase iron needs because blood carries iron in red blood cells, and every period removes some of that blood. The NHS periods guide puts typical loss at about 20 to 90ml over a period lasting around 5 days, with bleeding heaviest in the first 2 days. The higher the loss, the more iron the body has to replace.
The menstrual phase, days 1 to 5 of the cycle, is when this loss happens, but iron stores build up or run down over months. The 2025 JAMA review names menstrual bleeding as one of the most common causes of iron deficiency. It estimates that in high-income countries about 38% of non-pregnant women of reproductive age have iron deficiency without anaemia, and about 13% have iron deficiency anaemia.
How Do You Know If Your Period Is Heavy Enough to Lower Iron?
A period is likely heavy enough to affect iron if it meets the NHS markers for heavy menstrual bleeding (menorrhagia). The NHS heavy periods page lists changing a pad or tampon every 1 to 2 hours, needing 2 products together, bleeding for more than 7 days, and passing clots larger than about 2.5cm.
Needing a fresh pad every hour on days 1 and 2, with a tampon worn alongside it overnight, already meets two of those markers. Many women ask whether it is normal to feel drained for days after a heavy period, and the JAMA review lists fatigue, poor concentration and exercise intolerance among iron deficiency symptoms. Its authors conclude that "Iron deficiency and iron-deficiency anemia are common conditions that may cause symptoms such as fatigue, exercise intolerance, and difficulty concentrating."
Solu is a women's wellness app that maps cycle-phase-aware guidance across movement, nutrition, sleep, and energy, built for women tracking hormonal, cycle, and premenstrual symptoms. Logging energy and period symptoms in Solu across several cycles shows whether tiredness follows heavy months or appears regardless of bleeding.
What Should You Eat for Iron During Your Period?
Iron-rich foods eaten every day, not only on period days, are the most reliable way to meet the 14.8mg target. As of 2026, NHS guidance lists red meat, beans such as chickpeas and kidney beans, nuts, dried fruit such as apricots, fortified breakfast cereals and soy bean flour as good sources, and says most women can get all the iron they need from diet.
In the UAE, lentil soup and hummus are everyday meals that fall into the NHS beans and pulses group. Absorption depends on what is eaten alongside them, so pairing and timing matter as much as the food itself.
| Factor | Effect on iron | Source |
|---|---|---|
| Orange juice with an iron tablet | May help absorption | NHS |
| Tea or coffee | Can reduce absorption | NHS |
| Milk and dairy foods | Can reduce absorption | NHS |
| Wholegrain cereals (phytic acid) | Can reduce absorption | NHS |
| Tablets on alternate days | Fewer stomach side effects | 2023 trial |
Drinking tea or coffee away from iron-rich meals is the simplest change for most women. Solu's period-week food suggestions put iron-rich meals forward during the menstrual phase. Meals for the rest of the month are covered in the guide to eating for each phase of the cycle.
Should You Take an Iron Supplement for Heavy Periods?
An iron supplement is worth discussing with a GP if periods are heavy, but taking one without a blood test is not advised. The NHS says women with heavy periods may need supplements, and that doses over 20mg can cause constipation, nausea and stomach pain. The JAMA review lists oral iron, daily or on alternate days, as first-line treatment for confirmed deficiency.
The 2023 Swiss trial gave 150 iron-depleted young women 100mg of iron either daily or on alternate days. At the same total dose, the alternate-day group had fewer stomach side effects and less iron deficiency at 6 months (3.0% versus 11.4%). Broader supplement choices are weighed in the guide to which vitamins women should take daily, and iron before pregnancy in what to eat to get pregnant faster.
When Should You See a Doctor About Iron and Heavy Periods?
See a GP if periods are heavy, have been heavy for some time, or tiredness, breathlessness or pale skin persist after a period ends. The NICE heavy menstrual bleeding guideline, last updated in July 2026, recommends a full blood count for all women with heavy bleeding.
The JAMA review adds that iron deficiency is usually confirmed by a ferritin level below 30 ng/mL, so ask whether ferritin is included. The NHS also advises a GP visit for bleeding between periods or after sex, or severe period pain. Seek urgent care for fainting, chest pain or severe breathlessness. Low energy that returns once bleeding stops is covered in the guide to why energy rises the week after a period.
Key Takeaways
- The NHS sets iron needs at 14.8mg a day for women aged 19 to 49, against 8.7mg for men.
- About 38% of reproductive-age women in high-income countries have iron deficiency without anaemia, according to a 2025 JAMA review.
- Tea, coffee and dairy can reduce iron absorption, while orange juice may help absorb iron tablets.
- In a 2023 trial, alternate-day iron caused fewer side effects and less deficiency at 6 months.
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