Causes of anaemia

Anaemia happens when the level of haemoglobin in your blood is lower than it should be.

There are three main causes of anaemia:

  • not enough haemoglobin being produced, often because you don’t have enough iron in your diet
  • not enough red blood cells being produced by the bone marrow
  • too many red blood cells dying off – this is known as haemolysis.

When children get anaemia, it’s most often because they don’t have enough iron in their bodies. And this is usually because they’re not eating enough food with iron in it.

Adolescent girls are at risk of iron-deficiency anaemia if they have frequent, prolonged or very heavy periods.

About iron
Your child needs iron because it helps form haemoglobin.

For the first 4-6 months of life, your baby uses iron stored in his body from when he was in the womb. He also gets iron from your breastmilk and/or infant formula. This means that iron deficiency is rarely a problem early in life. If your baby was born prematurely or was very sick as a newborn, or you were iron deficient during late pregnancy, iron deficiency might be an issue.

Once your baby’s iron stores are used up, she needs to start eating food with iron in it. So when you’re introducing solid food, it’s best to start with and always include foods that are high in iron. Examples are infant rice cereal, cooked vegetables, minced meat or chicken, mashed cooked fish, tofu, peas, beans and lentils.

Most babies show signs they’re ready for solid food by about six months.

If your older baby drinks a lot of cow’s milk, her overall diet might not have enough iron. This is because cow’s milk is a poor source of iron and can stop the gut from absorbing iron properly. Also, drinking too much milk can decrease your baby’s appetite for solids.

Anaemia symptoms

If your child has anaemia, he might look very pale. A toddler might get very tired. Because toddlers’ energy levels go up and down, this can be hard to spot.

Your child might be cranky and hard to manage. Older children might be very tired, have a poor appetite and find it hard to concentrate at school.

If your child’s anaemia is caused by something other than iron deficiency, she might show specific symptoms of this underlying cause.

When to see your doctor about anaemia symptoms

Take your child to the doctor if your child:

  • looks very pale
  • is irritable
  • doesn’t have much energy
  • complains of frequent headaches.

It’s also a good idea to see your doctor or child and family health nurse if you want extra information about what to feed your baby – for example, if your child drinks large volumes of milk and doesn’t eat solids.

Tests for anaemia

If your child has anaemia, your doctor will usually order blood tests to work out what’s causing it.

Occasionally the results of the initial blood tests will show that your child needs some other tests. In this case, your child might need to see a paediatrician or a blood specialist (haematologist).

Treatment for anaemia

Anaemia treatment depends on the cause.

If your child has anaemia caused by not enough iron, adding iron-rich foods to his diet can help boost his iron levels. Iron-rich foods include:

  • iron-fortified cereals
  • legumes – for example, lentils and beans
  • meat – for example, red meat, chicken and fish
  • egg yolk
  • green vegetables
  • crushed sesame seeds – for example, tahini or halva.

Changing your child’s diet alone might not be enough. She might also need to take iron supplements (tablets or syrup) to help get her iron levels back to normal. Iron supplements can turn your child’s poo black or grey, and might cause constipation or tummy upsets. It’s a good idea to talk to your doctor about these and other side effects.

Occasionally, your child might need an infusion or injection of iron.

If the anaemia is caused by poor bone marrow function or haemolysis, your child might need more tests and treatment. Your child will probably need to see a paediatrician.

All iron supplements should be stored in a locked cupboard away from children. Iron overdose in a child can be fatal.

Prevention of anaemia

If your child eats a balanced diet after the age of 4-6 months, this can prevent anaemia caused by not enough iron. At 12 months, you can give your baby pasteurised, unflavoured, full-fat cow’s milk.

For more information on diet for your child, see your local child and family health nurse, GP or dietitian.