Milk allergyWhat is a milk allergy?
A milk allergy occurs when the body’s immune system incorrectly identifies proteins present in milk as a threat and sends antibodies to combat them. These antibodies then release chemicals that cause a range of harmful reactions in the sufferer.
How common is it?
Milk allergies are found most frequently in young children, with approximately 2.5% of children worldwide under the age of three affected. Milk allergies typically develop in the first year of life.
Fortunately, the majority of sufferers see their allergy disappear by the time they reach 16 years of age, but a small percentage (approximately 0.5%) have the allergy for life.
The difference between a milk allergy and lactose intolerance
Lactose intolerance and milk allergies are two separate conditions. While a milk allergy takes place in the immune system, lactose intolerance is a digestive issue. Lactose intolerance occurs when the body is unable to properly process lactose, a natural sugar found in milk, due to a lack of the required enzyme (i.e. lactase). The immune system is not affected or involved in lactose intolerance, and by the same token, a milk allergy is not a problem of the digestive system.
This is reflected in the most frequent symptoms of lactose intolerance which include abdominal pain, cramping, gas, diarrhoea, nausea, and vomiting. While all these reactions can also be caused by a milk allergy, milk allergies also cause other symptoms not shared by lactose intolerance (listed below).
Milk allergy symptoms
Negative reactions caused by a milk allergy can range from mild to severe and can take place shortly after consumption of the offending product, or up to several hours later.
Symptoms that may occur shortly after consuming milk-containing products include:
● Itching around the mouth and lips
● Swelling of the eyes, face, lips, tongue and/or throat
● Coughing, wheezing and shortness of breath
● Nausea or vomiting
● Anaphylaxis, a rare but severe and potentially life-threatening reaction
Symptoms that are more likely to emerge after a longer delay include:
● Abdominal pain and cramping
● Excessive gas
● Loose or bloody stools (can contain blood), diarrhoea
● Runny nose
● Watery eyes
What is anaphylaxis? How is it treated?
Anaphylaxis is an acute reaction of the immune system to an allergen that can cause a sufferer’s airways to become restricted, potentially resulting in death. While more prevalent in peanut and tree nut allergies, it is also possible for a milk allergy to cause this life-threatening reaction.
Anaphylaxis requires immediate treatment via the injection of an epinephrine shot (also known as an adrenaline shot). Even if epinephrine is administered, it is still necessary to visit the emergency department, as a secondary attack, called a biphasic reaction, can sometimes occur within half a day of the initial anaphylaxis reaction.
Epinephrine autoinjectors, which can be self-administered, are available either via prescription or over the counter.
How is a milk allergy diagnosed?
In consultation with an allergist or other specialist physician, a patient’s dietary history is scrutinised. Specifically, the type of food that was consumed around the time adverse symptoms were experienced are identified in addition to the details of the symptoms themselves (including how long they persisted and the time delay between food consumption and symptom onset).
A skin-prick test or blood test can be administered to determine the presence of immunoglobulin E antibodies, which arise as the result of an allergy.
What is the treatment for milk allergies?
While there is no direct cure for a milk allergy, it can be managed by the avoidance of dairy-containing food and beverages.
It is highly recommended for milk allergy sufferers to avoid all dairy products including items such as:
● All forms of milk, including whole, low-fat, non-fat, skim, condensed, powdered, flavoured, malted, goat’s milk, or other animals’ milk
● Butter, buttermilk
● Cheese or cheese-containing products, cottage cheese
● Custard and pudding
● Ice cream and gelato
● Sour cream
It is important to carefully read the nutritional information on food packaging to better manage a milk allergy. Clearly, any ingredients list including statements such as ‘contains: milk’, ‘may contain milk’, or ‘may contain traces of milk’ mean the containing product is to be avoided. However, there are a number of processed foods that can contain milk but are listed under a different name. The most common alternate names are:
● Casein, caseinate, rennet casein
● Whey (all forms)
● Chocolate, nougat, caramel
● Protein powders
● Artificial butter or cheese flavouring
● Ingredients with the prefix ‘lact-’ such as lactose, lactate, lactalbumin, lactoferrin, and lactoglobulin
A ‘milk-free’ or ‘dairy-free’ label is therefore not sufficient assurance that a given product is safe for a milk allergy sufferer to consume, as hidden sources of milk proteins may still be present.
Certain types of food are also more likely to contain milk or milk protein in some form. In some cases the product may come into contact with milk or milk protein in the preparation stage rather than being directly in the final product. For instance, restaurants sometimes flavour steaks with melted butter, which is not visible when served. Some other examples are:
● Brown sugar
● Egg substitutes
● Flavoured coffee
● Fruit bars, granola bars
● High protein flour
● Meats - e.g. canned tuna, luncheon meats, deli meats, hot dogs, sausages, pâtés
● Shellfish (sometimes dipped in milk to reduce odour)
Health and dairy products
Calcium and Vitamin D are the main substances milk allergy sufferers may lack in their regular diet. It is therefore necessary to ensure the intake of these nutrients from other sources. Calcium and Vitamin D supplements are available in tablet form and it is also possible to purchase calcium-fortified foods such as soy drinks, orange juice, and breakfast cereals. Almonds and other nuts, soft-boned fish such as salmon, legumes, and leafy vegetables such as spinach and kale all contain high quantities of calcium, while beef liver and fatty fish such as tuna, mackerel and salmon are all good sources of vitamin D.