Milk allergy vs lactose intolerance: What's the difference?

Do not confuse milk allergy with lactose intolerance; they are very dissimilar conditions. Milk allergy is a true allergy, mediated by immune factors, while Lactose intolerance is the inability to digest lactose.

Q. I am extremely worried about my newborn baby. I fed her some formula milk and she started to vomit. I took her to a paediatrician and the doctor said that it is possible my daughter has milk allergy. What is milk allergy?

Milk allergy is one of the most common food allergies to be found, occurring especially in children. Luckily, most of them outgrow this allergy by age three.

As you grow older, your digestive tract matures, and you are less likely to react to milk.

Milk allergy is actually an abnormal response mounted by the body's immune system - as most allergies are - to milk and products containing milk. The latter may include cheese and butter.

The usual cause of milk allergy is cow's milk. That is why all doctors advocate mother's breast milk for babies. Milk allergy can also stem from goat's milk, sheep's milk and buffalo milk.

Some children are allergic to cow's milk as well as soy milk.

Is milk allergy the same as lactose intolerance? My whole family, from my father and mother, have lactose intolerance.

No. Milk allergy is not the same as lactose intolerance. Milk allergy is a true allergy, mediated by immune factors.

Lactose intolerance is the inability to digest lactose, which is a type of sugar found in milk and dairy products. It is a genetic condition.

Lactose intolerant individuals have a deficiency of the enzyme lactase, which hydrolyses lactose into glucose and galactose.

This results in cramps, abdominal bloating, gas, flatulence, diarrhoea, rumbling stomach and sometimes vomiting after consuming these milk and milk products.

What causes milk allergy?

In milk allergy, your child's immune system happens to be hypersensitive to certain milk proteins like casein and whey. These proteins trigger the release of Immunoglobulin E (IgE), and the resultant immune response involves the release of histamine.

Casein is the curd, which is actually the solid part of the milk which appears when it is curdled. Whey is the liquid part of the milk that remains after it is curdled.

You may be allergic to one or both.

How do I recognise the symptoms of milk allergy? My baby would not be able to tell me anything that is bothering her because she's too young.

The symptoms will vary from child to child. Some will occur within minutes to hours of ingesting the milk or eating the milk products. Look out immediately for:

> Weals or raised reddish patches (urticaria or hives) on your child's skin.

> Vomiting.

> Wheezing or hoarse breathing.

Then there are signs and symptoms that may take a bit more time to manifest:

> Diarrhoea or loose, soft stools which may or may not contain some blood.

> Stomach cramps or colic (for babies).

> Coughing.

> Wheezing: this may also occur later rather than earlier.

> Skin rash, sometimes itchy, around the mouth area.

> Runny nose.

> Watery eyes.

A very bad complication to look out for is anaphylaxis, which is a life-threatening allergic reaction that may result in severe constriction of lung airways, flushing, itching, and worse of all, anaphylactic shock resulting in a drop in blood pressure.

For milk allergies, whether your child's symptoms are mild, moderate or severe, it's always best to consult a doctor immediately. Go as early as you can because of the possible complications.

Are certain children more prone to developing milk allergy?

Yes. A child who is allergic to other things is also more prone to develop milk allergy. However, it is usually the milk allergy that develops first.

If your child has atopic dermatitis (inflammation of the skin), a family history of food allergy (such as one or both parents have food allergy, hay fever, asthma, eczema or any other type of allergic diseases), he is at greater risk of developing milk allergy.

What can I do to treat my child's milk allergy?

The only way is to make sure that your child avoids milk and milk products completely, which can be difficult sometimes.

Medications that help include antihistamines, or in case of anaphylactic shock, epinephrine injections. Some parents even have epinephrine and some syringes at home as an emergency measure just in case they can't get to the hospital in time.

Dr YLM graduated as a medical doctor, and has been writing for many years on various subjects such as medicine, health advice, computers and entertainment. For further information, e-mail The information contained in this column is for general educational purposes only. Neither The Star nor the author gives any warranty on accuracy, completeness, functionality, usefulness or other assurances as to such information. The Star and the author disclaim all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.

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