Lactose intolerance

Lactose intolerance

What is it?

Lactose intolerance is the inability to absorb lactose, which is the main sugar found in milk. The condition can be quite common in young children, as the enzyme the body uses to break down lactose has not yet matured. The condition is most commonly seen in premature babies. Lactose is composed of two sugars, which must be broken down to glucose and galactose by a lactase enzyme in order to be digested. This enzyme is found in the small bowel.

If this enzyme is absent from the child’s body or is only present in low levels, then their body is unable to break down the lactose and the symptoms become apparent. After the age of two a child’s body produces less lactase, although the symptoms may not show up until years later. Both children and adults can suffer from lactose intolerance.

The condition can cause reactions to milk products and foods which contain lactose. Foods containing lactose include:

When shopping for food, parents should look for information on the labels regarding the content of the food.

What are the symptoms of lactose intolerance?

Symptoms include:

These usually occur between 30 minutes and two hours after food has been taken. Children between birth and five years may experience slow growth.

How is it diagnosed?

Doctors can perform a number of tests to see whether lactose intolerance is the problem. These might not be given to infants or the very young, as large doses of lactose may leave them prone to dehydration.

The first test involves measuring the blood sugar levels in the body before and after the person drinks a liquid containing lactose. If the sugar level rises they are not lactose intolerant.

A breath test can also be used. The person drinks a solution and their breath is tested for the presence of hydrogen, which is produced if the lactose has been fermented.

Another test, called an endoscopy, involves the insertion of a small scope (tube) into the stomach and small intestines via the mouth. It enables the doctor to take a sample from the lining. The doctor may also want to test the acidity of the patient’s stool.

How is it treated?

Some children may be advised to cut down on the dairy intake in their diet. In severe cases a dietitian may advise a lactose-free diet. Medicines are available to treat the condition, some of which come in a liquid form to be added to milk, while others can be chewed before a meal or a snack. Some children may have to substitute milk with a soya formula.

Milk is an essential part of a child’s diet because it contains calcium, which is necessary for strong bones. Therefore, if milk or dairy products are to be cut from the child’s diet it is important to substitute them with calcium-rich foods.

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