Lactose intolerance: babies and children

Lactose intolerance is when the child can’t effectively break down the sugar lacose that is present in milk and dairy products. symptoms include wind, stomach pain, diarrhea and bloating. This happens usually in children older than 5 years when the child’s lactase enzymes gradually start to decrease. Children and teenagers with lactose intolerance should change to a healthy, low-lactose diet. See your doctorfor a proper assessment of your child’s condition.

What is lactose intolerance?

Lactose intolerance is when the body can’t break down lactose . This problem happens because there isn’t enough lactase in the stomach.

Lactose is a complex sugar. It’s present in all breastmilk, dairy milk and other dairy products. It makes up around 7% of breastmilk and infant formula.

Lactase is an enzyme. Enzymes break down food chemicals so the body can use them.

Lactose is important for your baby’s health and development. It provides around 40% of your baby’s energy needs and helps him absorb calcium and iron.

Causes of lactose intolerance

There are three main causes of lactose intolerance.

Lactase non-persistence (hypolactasia)
This happens when your child’s lactase enzymes gradually start to decrease. This is genetic and very common – about 70% of people have this type of lactose intolerance. Symptoms can start to happen after the age of five but are usually more noticeable in teenagers and young adults. Children can usually still tolerate small amounts of lactose in their daily diets.

Congenital lactase deficiency (alactasia)
This happens when babies are born with no lactase enzymes at all. This is genetic but extremely rare. Babies with this kind of lactose intolerance have severe diarrhoea from the first day of life. To thrive, they need a special diet from the time they’re born.

Secondary lactose intolerance
This can happen if a child’s digestive system is upset by infections like gastroenteritis, which alter the lining of the stomach and small intestine. This kind of lactose intolerance is short term and usually improves after a few weeks.

Conditions like coeliac disease can also cause secondary lactose intolerance. Once these conditions are being managed properly, lactose intolerance should be less of a problem.

Common symptoms of lactose intolerance

Symptoms of lactose intolerance in babies and children include:

  • wind
  • stomach pain and bloating
  • diarrhoea.

Sometimes lactose intolerance is confused with food allergies like cow’s milk allergy. Some common food allergy symptoms include vomiting, blood or mucus in diarrhoea, hives and swelling around the eyes – these aren’t symptoms of lactose intolerance. If your child has symptoms like these, you should see your doctor for a proper assessment.

Diagnosing lactose intolerance

These are the two main ways to diagnose lactose intolerance:

  • Hydrogen breath test: this tests the amount of hydrogen gas in a child’s breath following eating a certain amoung of lactose containing food. Lactose-intolerant children have higher levels of hydrogen in their breath.
  • Elimination diet: this involves removing foods containing lactose from a child’s diet to see whether symptoms improve. If the symptoms come back once the foods with lactose are reintroduced, lactose intolerance is apparently  the cause of the problem.

Because some of the symptoms of lactose intolerance and food allergy are similar, diagnosing lactose intolerance can sometimes be tricky.

Treatment: lactose intolerance in babies

Congenital lactase deficiency
If your baby has congenital lactase deficiency, your doctor will guide your child’s treatment. Again, this is an extremely rare condition. 

Secondary lactose intolerance
For a breastfed baby with secondary lactose intolerance caused by gastroenteritis, you should be able to continue breastfeeding.

If your baby is formula fed or you’re considering giving him formula, consult your doctor or a dietitian before using or changing to a low-lactose or lactose-free infant formula. If your child is under six months, avoid using soy-based infant formula.

Treatment and management: lactose intolerance in older children 

If your older child is diagnosed with lactose intolerance, you can reduce the amount of lactose in her diet. But you don’t need to get rid of products with lactose completely, especially if your child eats only small amounts of them with other foods during the day.

The following food and diet tips can help.

These foods are OK:

  • cheeses with very low lactose content – brie, camembert, cheddar, colby, edam, fetta, gouda, havarti, mozzarella, parmesan, halloumi, Swiss and Tilstat
  • yoghurt – the bacteria in yoghurt breaks down the lactose so it’s usually fine for your child to eat
  • calcium-fortified soy products – soy yoghurt, soy milk, soy ice-cream and soy cheese
  • lactose-free cow’s milk
  • butter and cream – these contain only small amounts of lactose and are usually fine to eat
  • bread, cereals, fruit, vegetables, meat and other protein foods
  • full-fat milk – the fat in full-fat milk gives your child’s body longer to digest lactose.

Watch out for these foods:

  • milk ice-cream and milk desserts
  • cream cheese, processed cheese and cheese spread
  • muesli bars
  • instant mashed potato and vegetables with added milk or white sauces.

Check the ingredients in these foods:

  • biscuits, cakes and cake mixes
  • soups
  • mayonnaise
  • milk chocolate.

You may also talk to your doctor  if you’re thinking of using Lacteeze tablets or drops that break the sugar lactose sugar eaten by your child.