Melbourne Holistic Health Group

Published in Articles - Children's health on 06 September 2011 by Melbourne Holistic Health Group

Dairy allergy and intolerance are terms which are often confused in everyday conversation. A true food allergy provokes the body’s immune system producing antibodies* to specific food proteins, while intolerance does not involve the immune system but still causes adverse reactions. Any true food allergy has the potential to result in anaphylaxis** and is therefore a serious medical condition.

True milk allergy is most likely to affect infants, who often grow out of this allergy by childhood. Milk intolerance however may either be lactose intolerance or milk protein intolerance and may persist through childhood, adolescence and beyond. It is therefore important to distinguish whether the reaction to dairy is a milk allergy, lactose intolerance or milk protein intolerance. Many symptoms of milk intolerance are similar to other food intolerances and therefore may require assessment by your naturopath. As milk and dairy products do contribute a number of important nutrients, particularly in growing children, it is important to look at suitable alternatives where dairy is excluded.

Dairy milk allergy

Milk allergy is an immune reaction (IgE mediated) to one or more of the proteins found in milk. Children can react to proteins in milk produced by any animal including goat or sheep’s milk; however, cow’s milk allergy is most frequently encountered.

The most common milk allergy is to alpha S1-casein in cow milk and affects somewhere between 2% and 3% of infants in developed countries. Milk allergy can be a serious problem because some children develop anaphylaxis; however, the most common symptoms include skin rashes, hives, vomiting, diarrhoea or constipation, stomach pain and flatulence, infantile colic, eczema and wheezes.

It is estimated that 85-95% of children grow out of their milk allergy by the age of 3 years. Strict avoidance of all milk and milk products is required for infants or children with a milk allergy. Given the high incidence of dairy milk allergy the National Health and Medical Research Council (NHMRC) recommends that children under the age of 12 months should not be given cows’ milk.

Lactose intolerance

Lactose intolerance is caused by a genetic deficiency of the enzyme lactase, which breaks down the milk-sugar lactose. This is not an allergic reaction. Because lactose is malabsorbed in the digestive tract, it has an osmotic effect on the bowel (increases faecal water levels) and is rapidly fermented by intestinal bacteria. The effect of this may cause a number of symptoms such as bloating, flatulence, cramps, diarrhoea and loose stools. The degree of severity of these symptoms varies between lactose intolerant individuals. There is often a ‘threshold’ of lactose tolerance and it is not always necessary to exclude all dairy products. Most children who have lactose intolerance can actually tolerate small amounts of milk, yoghurt and hard cheese. Yoghurt may be better tolerated by some children (and adults) due the bacterial cultures present which consume lactose as a fuel, thereby reducing overall lactose levels.

Milk protein intolerance

Milk protein intolerance is a delayed reaction to a milk protein and can produce a range of symptoms very similar to milk allergy symptoms. However unlike milk allergy there is no IgE mediated immune response, and it does not have the potential to result in anaphylaxis. Blood allergy testing is not available for milk protein intolerance and an elimination diet is considered the ‘gold standard’ in diagnosis. Your naturopath will show you haw to do this.

Symptoms of milk protein intolerance may include gastrointestinal symptoms such as diarrhoea, constipation, stomach pain and flatulence; dermatological symptoms such as skin rashes, hives and atopic dermatitis; as well as respiratory complaints such as wheezing and allergic rhinitis (runny nose and sneezing).

Like milk allergy, avoidance of milk and milk products is advised for these children. Children (and adults) who react to milk protein can also react to soy protein in soy milk and these children will need to avoid both types of milk. Fortunately this is less common.

Not all dairy milk protein is the same

Milk contains many different types of proteins, caseins being the most abundant followed by whey. The proportion of protein in animal milk varies between different species and between different breeds of animal. Cow’s milk comprises only 3-4% protein. Caseins (approximately 80%) and whey (approximately 20%) are the major protein classes in cow’s milk. Beta-casein is one of the major casein proteins and the 2 most common proteins of this type are A1 and A2.

Most milk is a mixture of A1 and A2 milk. Some breeds of cows such as Fresians, produce mostly A1 milk, whereas other breeds like Guernseys, as well as sheep and goats, produce mostly A2 milk. Because the composition of the proteins in these milks is different, some children with a cow’s milk protein intolerance (not allergy) may tolerate better A2 milk, goats or sheep milk and foods made of these milks such as cheese and yogurt.

A1 vs A2 milk

It has been suggested that A2 milk is less allergenic than A1 milk and may also provide protection against a number of disease conditions ranging from autism in children as well as schizophrenia, diabetes and heart disease. Food Standards Australia and New Zealand has considered the limited evidence on the effects of the two milks and concluded that no regulatory action needs to be taken. It is also important to note that the Medical Journal of Australia reported in 2004 that A2 milk has the potential to be allergenic and should not be used by those with IgE-mediated cow’s milk allergy. It may however, be tolerated by people who have a milk protein intolerance.

Dairy, calcium and dairy alternatives

One of the most important nutrients that dairy provides is calcium, other nutrients include protein, vitamin B2 and vitamin A. Calcium is particularly important during childhood and adolescence when bones are rapidly growing and are most sensitive to dietary calcium. Where dairy is excluded from a child’s diet it must be ensured that there is adequate calcium intake. Sources of calcium other than dairy include fish with edible bones such as sardines, tofu, spinach, broccoli, sesame seeds and almonds. Alternatives to dairy milk include soy, rice and oat milk and as well as nut milks such as almond milk. Calcium enriched versions of these milks should be chosen. A variety of alternatives to other dairy products exist such as soy cheeses and ice-cream. However soy and nut milks and products may not always be a suitable alternative.

Particular caution must be exercised with infants as multiple allergies may co-exist with a dairy allergy. Your naturopath can assist you in choosing high calcium dairy alternatives for your child.

* Antibodies: A specialised immune protein produced in response to an antigen (any substance that can induce an immune response) being introduced to the body.
** Anaphylaxis: An immediate systemic allergic (IgE mediated) reaction, which may result in airway obstruction from spasm in the airways, hives and in some cases death.

Other articles on children's health include:

• Feeding infants and toddlers
• Fever in children
• Impact of fish oils on learning and behaviour in children
• Children friendly healthy recipes