Iron

Iron is an essential mineral for making haemoglobin, the protein that carries oxygen in the blood. Women of childbearing age, pregnant women and vegans are most at risk of not meeting their needs.

Quick facts

  • Contributes to normal formation of red blood cells and haemoglobin

Iron is the mineral whose deficiency is most common worldwide, especially among women of childbearing age.

What is iron?

It is an essential mineral. About two thirds of the body's iron is in the haemoglobin of red blood cells; the rest is stored, mainly as ferritin, or forms part of muscle proteins and enzymes.

What does iron do?

According to the health claims authorised in the European Union, iron contributes to:

  • normal formation of red blood cells and haemoglobin
  • normal oxygen transport in the body
  • the reduction of tiredness and fatigue
  • normal cognitive function and normal energy-yielding metabolism
  • the normal function of the immune system

Which foods contain iron?

  • Haem iron (better absorbed): red meat, liver, clams, mussels and cockles, and fish.
  • Non-haem iron (less well absorbed): legumes, nuts, seeds, whole grains and leafy green vegetables.

How to absorb iron better

  • Vitamin C contributes to increased iron absorption: pair legumes with peppers, tomato or a piece of fruit.
  • Coffee, tea, calcium and phytates reduce it: keep them at least one to two hours apart from iron.

How much iron do you need per day?

EFSA recommends 11 mg a day for men and postmenopausal women, and 16 mg a day for women of childbearing age. The NRV on labels is 14 mg.

At IVB, FerroPlus provides 18 mg of iron as bisglycinate (Ferrochel®) with 100 mg of vitamin C, vitamin B12 and folate. Iron is also included in GestaNatal and VitalNatal Woman.

Types of iron

  • Ferrous bisglycinate: iron bound to two glycine molecules. Usually better tolerated by the digestive system.
  • Ferrous sulphate, fumarate and gluconate: the classic forms; more often cause constipation or stomach upset.

Safety

  • Only take iron if you need it: if you suspect a deficiency, ask your doctor for a blood test.
  • It may darken stools, which is normal and harmless.
  • Keep it apart from levothyroxine, calcium, stomach protectors and some antibiotics.
  • Keep out of reach of children: an iron overdose is dangerous for them.

Frequently asked questions

What does low ferritin mean?

Ferritin reflects the body's iron stores. A low value usually means those stores are running down, even before haemoglobin falls. Your doctor should interpret your blood test and decide on treatment.

What are the signs of low iron?

The most common are tiredness, pallor, poor concentration, hair loss, brittle nails or breathlessness on exertion. They are non-specific, so confirmation always requires a blood test.

When should I take iron?

It is best absorbed on an empty stomach or with a light meal, together with vitamin C, and away from coffee, tea and dairy. If it upsets your stomach, take it with food.

Is it better to take iron every other day?

A study in women with low iron stores found that taking it on alternate days increased the proportion of iron absorbed from each dose (Stoffel 2017). Always follow the regimen your healthcare professional recommends.

References
  1. EFSA NDA Panel. Scientific Opinion on Dietary Reference Values for iron. EFSA Journal. 2015;13(10):4254.
  2. Stoffel NU, Cercamondi CI, Brittenham G, et al. Iron absorption from oral iron supplements given on consecutive versus alternate days and as single morning doses versus twice-daily split dosing in iron-depleted women. Lancet Haematol. 2017;4(11):e524-e533.
  3. National Institutes of Health, Office of Dietary Supplements. Iron: Fact Sheet for Health Professionals.
  4. Commission Regulation (EU) No 432/2012 establishing a list of permitted health claims made on foods, as amended.