Milk allergy: is it a milk allergy or lactose intolerance?

 

Milk allergy is one of the most common food allergies, especially in children. If you have a milk allergy, you should ideally switch to a milk-free diet – and also make sure your intake of important nutrients such as calcium and vitamin B12 stays optimal. 

Milk is found in many more foods than you think: in baked goods, ready-made products, sauces – and people often only notice this if they cannot tolerate milk. If you have a milk allergy, you have to pay special attention to which foods you can eat. Even the smallest amount of a certain food can cause allergic reactions ranging from an itchy throat to diarrhoea.

Read on to find out more specifically about what happens in your body when you have a milk allergy, experience milk allergy symptoms and how you can change your diet if you are allergic to milk. You will also gain insights into milk allergy in babies and in children, as well as which nutrients you may need to consume more of to make up for a milk-free diet.

What is milk allergy?

Milk allergy is one of the most common food allergies in the world. It mainly affects babies and young children under the age of five. The allergy often disappears during childhood or adolescence – but not always.^[1] It is difficult to say exactly how many people are affected: according to the European Centre for Allergy Research Foundation, 2.3 per cent of people suspect they have a milk allergy, but only 0.6 per cent have actually been diagnosed.^[2]

Tip: Read all about egg allergy, another common food allergy, in our Health Portal.

An allergy is always a reaction of the immune system to allergens – that is, certain substances that the body mistakenly classifies as a threat. In the case of milk allergy, these are proteins found in cow’s milk. Most of these proteins belong to caseins – which are in the solid part of the milk – and to whey proteins. The allergens in milk are also found in dairy products such as cheese, curd, yogurt and cream.^[3]

Heat can destroy whey proteins – but most people are allergic to different allergens in milk. And most of them are heat-resistant. So, in most cases, boiling milk beforehand or buying processed food will not protect you from developing any milk allergy symptoms.^[4]

Is there a difference between milk allergy and lactose intolerance?

The difference between a milk allergy and lactose intolerance is quite simple. Where an allergy involves an immune reaction in your body – and can be life-threatening, an intolerance can trigger discomfort in your stomach, such as bloating or diarrhoea. The severity of lactose intolerance symptoms experienced can also depend on how much lactose you consume; with an allergy, even consuming small traces of the allergen can be extremely dangerous for those who are very allergic.

The standard lactose intolerance test used by many doctors is also completely different to the allergy test – a blood test or skin prick test, for example – you would take to diagnose a milk allergy. A lactose intolerance test is often a hydrogen breath test that measures the concentration of hydrogen and methane in your breath after consuming solutions containing lactose.

For more information on the differences between a food allergy vs intolerance or on lactose intolerance, head over to our dedicated Health Portal blog articles.

What causes milk allergy?

Scientists cannot yet say exactly how allergies develop. What is clear is that our immune system initiates defensive reactions when we have an allergy. The composition of our gut microbiome – that is, the bacteria in our gut, is currently being considered as a possible cause of an allergy.

To find out more about why our gut flora is important for promoting various health benefits, head over to our Health Portal article.

Genetic predisposition also plays a role. Children have a higher risk of developing a food allergy such as milk allergy if one or both parents suffer from allergies, asthma or neurodermatitis.^{[1, 5, 6]}

How does milk allergy affect the body?

During an allergic reaction, the body produces a greater number of IgE antibodies. These antibodies ensure that the cells of our immune system release the messenger substance histamine when the allergen enters the body. Histamine then triggers inflammation in mucous membranes – and thus typical allergic reactions.^[7]

Please note: As discussed above, a milk allergy is not the same as lactose intolerance, and the two health conditions must be diagnosed and treated differently. With lactose intolerance, the intestine has difficulty processing the milk sugar (lactose).^[9] In contrast to an allergy, lactose intolerance symptoms include discomfort in the gastrointestinal tract, such as flatulence and diarrhoea.^{[7, 9]}

Is milk allergy in babies common?

Cow’s milk allergy is the most common form of food allergy in babies and young children. First allergic reactions usually start when you introduce your child to solid food after breastfeeding. In very rare cases, the allergy may already become apparent during breastfeeding.

Most children grow out of the allergy with age. One study of nearly 300 children showed that 50 per cent of the children were no longer allergic to cow’s milk by their fifth birthday. In other studies, 80 per cent of the children no longer had symptoms by the time they went to school. However, if the allergy persists into adulthood, it is often a health condition you have for life.^{[1, 2, 10]}

Many children who are allergic to milk also have other allergies. A milk allergy is often the first to become apparent. Food allergies also often occur together with neurodermatitis.^[3]

Do I need to look out for cross-reactivity with a milk allergy?

If you have an allergy, you may develop cross-allergies. This is when your immune system reacts to allergens that are similar to the triggers of your allergy. With cow’s milk, for example, cross-reactions with other types of milk occur in about 90 per cent of cases, especially with goat’s and sheep’s milk. A cross-allergy with beef is possible, but rarer.^[1]

Find out more about cross-reactivity with other foods in our dedicated Health Portal article.

What is really in milk?

Milk provides us with essential vitamins, such as vitamin B12 and vitamin B2, and the minerals magnesium, iron and zinc. Above all, however, it is our main source of calcium. Due to its calcium content, milk helps promote bone density in old age and thus protects against osteoporosis and bone fractures.^{[11, 12]} Like all food, however, milk contains only very small amounts of vitamin D – you cannot receive sufficient levels of the sunshine vitamin by consuming dairy products. This only works in countries where vitamin D is added to milk, such as in the United States and Scandinavia.

If the fat content of milk decreases, so does the nutrient content. So, low-fat milk not only contains less fat, but also less iron and vitamin A, for example.

Milk consists of 90 per cent water; the rest is fat, protein and carbohydrates in the form of lactose. The fats contained are mainly saturated fatty acids, which should only make up a small part of the diet. The body can utilise the proteins in milk very well.^[11]

If you cannot consume milk, due to milk allergy or lactose intolerance, you should ensure that you receive enough of the vitamins and nutrients necessary for staying healthy. If you’re not sure about your nutrient levels, you can opt to take a nutrient and mineral deficiency test – at home or at a doctor’s office – and if a nutrient deficiency has been confirmed, you can stock up on various supplements, such as vitamin D, calcium, iron, zinc and magnesium. If you are  vegan, you would also benefit from making sure that you still receive these important nutrients after eliminating milk from your diet.

What are typical milk allergy symptoms?

Milk allergens often trigger strong to very strong and very different reactions. Milk allergy symptoms can occur not only in the mouth and gastrointestinal tract, but also on your skin and in your respiratory tract:^{[4, 9]}

• Respiratory: breathing difficulties, coughing, runny nose, swelling of the larynx
• Skin: hives (urticaria), sudden swelling (angioedema), itching
• Mouth: swelling around the mouth
• Gastrointestinal tract: nausea, vomiting, abdominal pain, diarrhoea

Generic symptoms such as fatigue can also indicate a milk allergy. Symptoms usually appear a short time after you have consumed milk. This is also called an immediate-type allergy, as the reaction occurs immediately after consumption.^{[4, 9]}

Some people experience what is called an anaphylactic shock, also called anaphylaxis, which is the most severe form of allergic reaction. The shock can cause shortness of breath, a rapid heartbeat, dizziness and circulatory problems, and even unconsciousness – it can be life-threatening. Milk allergy triggers ten to twenty per cent of all food-induced anaphylactic shocks. Only nut allergies are more frequently responsible.^{[4, 9, 14]}

How do you get tested for a milk allergy?

Doctors are able to diagnose an allergy when:^[22]

• you experience symptoms when coming into contact with the allergen
• your body is sensitised to the allergen – that is, it produces too many specific IgE antibodies – this can be determined with a blood test or with a skin prick test
• in a prick test, doctors scratch the allergen under the skin with a lancet, which results in wheals and red skin

Alternatively, an allergy test in a laboratory can determine the number of certain IgE antibodies in your blood. A greater-than-normal number of these antibodies also indicates that you have a sensitivity. These days, it is possible to take specific allergy tests, such as dairy and egg allergy tests or nut allergy tests, that screen for these specific antibodies.

To be absolutely sure, you can take a provocation test. For this type of health test, you are given the allergen under medical supervision. A doctor observes whether you experience any symptoms.

Did you know that even 2,000 years ago, there were reports of cases of allergic reactions to cow’s milk? But it was only 50 years ago that experts recognised allergens and what happens in the body with an allergy.^[2]

Milk allergy treatment: how do I treat an allergy?

If you have been diagnosed with a milk allergy, there is only one real form of milk allergy treatment: you have to cut milk and dairy products out of your diet. So far, there is no cure for milk allergy.

But there are a few things to keep in mind. On the one hand, milk is found in many sauces, baked goods and ready-made products, and even small amounts can trigger milk allergy symptoms. On the other hand, nutrients such as calcium must be consumed from other sources if you have to eliminate milk from your diet.^[1]

Please note: Medicines can also contain milk and milk components. Ask your doctor or pharmacist. 

Milk allergy treatment through medicine

Antihistamines can relieve your symptoms of allergies. These medicines are also known as allergy tablets. However, they are only suitable for short-term use.

If you have already suffered an anaphylactic shock, your doctor will prescribe an anaphylaxis emergency kit. The kit contains, among other things, an adrenaline pen and a cortisone preparation and can be life-saving in case of shock.^[18]

What is immunotherapy (hyposensitisation)?

For some allergies, it is already possible to undergo immunotherapy (also called hyposensitisation). Doctors administer small doses of the allergen over a period of years. Over time, the immune system is supposed to get used to the allergy triggers and lower the severity of its reaction.

For food allergies, however, this type of treatment is still being developed and researched. So far, there have only been clinical studies – with initial success in the case of peanut allergies, but also with many side effects. Immunotherapy is thus not yet a form of possible milk allergy treatment.^[18]

What can I eat with a milk allergy?

People with milk allergy usually react to all products made from milk. As an allergy sufferer, you should avoid the following foods, among others:^{[1, 15]}

• buttermilk and similar products such as kefir and ajvar
• cheese and anything containing cheese
• yogurt and curd
• ice cream and pudding
• cream and butter

Soy drinks are a popular milk alternative. But beware – soy also very often triggers allergies, and people who are prone to food allergies have an increased risk of developing other allergies.^{[1, 15]}

Preventing milk allergy symptoms: which products you should avoid

Milk is found in many processed foods – even in those in which you might not directly suspect it. You should therefore study the contents on the packaging and ask in restaurants or bakeries, if in doubt.

Milk can be hidden in the following foods, among others:^[3]

• bread, cakes and other baked goods
• meatballs, breaded meat and breaded fish
• sauces, soups, mayonnaise and vegetarian spreads
• sweets, such as chocolate, nougat and caramel
• protein powder with casein or whey protein

According to the Food Standards Agency in the United Kingdom, manufacturers must indicate on their products if they contain milk products. Restaurants and bakeries are also obliged to answer your questions about allergens.^[23]

You can easily replace most of the nutrients found in milk with other foods. However, it is worth paying attention to calcium intake if you have an allergy. Milk is the main source of this essential mineral in the Western world.

In addition to dairy products, good sources of calcium are:^[17]

• certain vegetables such as broccoli, kale and rocket
• calcium-rich mineral water
• nuts such as hazelnuts and Brazil nuts

The recommended calcium intake for adults is 1,000 milligrammes per day. You can meet your calcium requirement with – for example, 250 millilitres of milk and two slices of Emmental cheese (50 to 60 grammes).^[17]

Milk substitutes: which milk substitute is healthiest?

These days, there are many milk alternatives to choose from, be it soy, coconut, almond, hemp or oat. Supermarkets now give us a plethora of these milk alternatives to choose from, and it’s not always easy to know which milk alternative to pick. While research is still ongoing regarding the health benefits of milk alternatives, the following facts have been confirmed.

• Soy milk is a good source of protein
• Coconut milk contains healthy saturated fats
• Rice milk contains more carbohydrates, which is useful if you want to boost your energy
• Oat milk can be used to lower LDL cholesterol
• Almond milk is considered a good low-fat milk alternative^[24]

In terms of children, from the age of one, you can feed your child soy milk if they do not have a soy allergy. Soy is high in protein, and soy drinks are often fortified with calcium and B vitamins. You can also cook and bake well with soy drinks and other milk alternatives such as oat, rice and almond drinks, and prepare desserts such as various desserts and rice pudding.

However, these plant-based drinks are only suitable as a supplement if your child can already eat other foods such as meat, grains, fruits and vegetables.^[1,19]

According to one study, about 75 per cent of children with milk allergies can tolerate dairy products that have been cooked in the oven at high temperatures. In the study, the researchers tested this with waffles and muffins as well as the cheese on pizzas. It is possible that baked dairy products can even increase the chance of the allergy disappearing. But be careful: you should only try this out with a doctor.^[21]

Milk allergy versus lactose intolerance – at a glance

What is milk allergy?

Milk allergy is one of the most common food allergies worldwide. It occurs mainly in young children and disappears in many sufferers during childhood and adolescence. With an allergy, the immune system initiates defence reactions against harmless proteins in milk, which leads to milk allergy symptoms.

What are typical milk allergy symptoms?

If you have an allergy, symptoms include gastrointestinal discomfort such as diarrhoea and flatulence, skin irritation, swelling in the mouth and respiratory issues. Sometimes, there are also generic milk allergy symptoms such as headaches and fatigue.

Which foods should I avoid if I have a milk allergy?

Milk is not only found in dairy products such as cheese, yogurt, quark and cream. Many baked goods and ready-made products also contain milk – for example, sauces, sweets and processed meat products.

What information is there on milk allergy in babies?

When it comes to a milk allergy in babies, you as a parent should make sure that they have a sufficient supply of B vitamins and calcium. If babies are also allergic to breast milk, it may make sense to give your child special food. It is best to consult your paediatrician, allergist or nutritionist.

Sources

^[1]        H. Hochwallner, U. Schulmeister, I. Swoboda, S. Spitzauer, und R. Valenta, „Cow’s milk allergy: From allergens to new forms of diagnosis, therapy and prevention“, Methods, Bd. 66, Nr. 1, S. 22–33, März 2014, doi: 10.1016/j.ymeth.2013.08.005.

^[2]        dem European Centre for Allergy Research Foundation, „Kuhmilchallergie“, ECARF. http://www.ecarf.org/info-portal/allergien/kuhmilchallergie/ (zugegriffen März 15, 2018).

^[3]        „Milk allergy - Symptoms and causes“, Mayo Clinic. http://www.mayoclinic.org/diseases-conditions/milk-allergy/symptoms-causes/syc-20375101 (zugegriffen März 16, 2018).

^[4]        A. Fiocchi u. a., „Diagnosis and Rationale for Action against Cow’s Milk Allergy (DRACMA): A summary report“, Journal of Allergy and Clinical Immunology, Bd. 126, Nr. 6, S. 1119-1128.e12, Dez. 2010, doi: 10.1016/j.jaci.2010.10.011.

^[5]        D. Graham-Rowe, „Lifestyle: When allergies go west“, Nature, Bd. 479, Nr. 7374, S. S2–S4, Nov. 2011, doi: 10.1038/479S2a.

^[6]        B. Björkstén, „Genetic and environmental risk factors for the development of food allergy“, Curr Opin Allergy Clin Immunol, Bd. 5, Nr. 3, S. 249–253, Juni 2005.

^[7]        H. Kasper und W. Burghardt, Ernährungsmedizin und Diätetik, 12., überarb. Aufl. München: Elsevier, Urban & Fischer, 2014.

^[8]        „What Is Casein? Foods With Casein, Casein Allergies, and More“, WebMD. https://www.webmd.com/allergies/casein-allergy-overview (zugegriffen März 09, 2018).

^[9]        C. Schäfer, A. Constien, und I. Reese, Praxisbuch Lebensmittelallergie Der sichere Weg zur richtigen Diagnose und optimalen Therapie bei Allergien und Unverträglichkeiten. München: E-Books der Verlagsgruppe Random House GmbH, 2009.

^[10]      R. A. Wood u. a., „The natural history of milk allergy in an observational cohort“, J. Allergy Clin. Immunol., Bd. 131, Nr. 3, S. 805–812, März 2013, doi: 10.1016/j.jaci.2012.10.060.

^[11]      S. W. Souci, W. Fachmann, H. Kraut, G. Andersen, K. Soyka, und Deutsche Forschungsanstalt für Lebensmittelchemie, Lebensmitteltabelle für die Praxis Der kleine Souci/Fachmann/Kraut. Stuttgart: Wissenschaftliche Verlagsgesellschaft Stuttgart, 2011.

^[12]      R. Rizzoli, „Dairy products, yogurts, and bone health“, The American Journal of Clinical Nutrition, Bd. 99, Nr. 5, S. 1256S-1262S, Mai 2014, doi: 10.3945/ajcn.113.073056.

^[13]      D. Kusche u. a., „Fatty acid profiles and antioxidants of organic and conventional milk from low- and high-input systems during outdoor period“, Journal of the Science of Food and Agriculture, Bd. 95, Nr. 3, S. 529–539, Feb. 2015, doi: 10.1002/jsfa.6768.

^[14]      J. D. Kattan, R. R. Cocco, und K. M. Järvinen, „Milk and Soy Allergy“, Pediatric Clinics of North America, Bd. 58, Nr. 2, S. 407–426, Apr. 2011, doi: 10.1016/j.pcl.2011.02.005.

^[15]      G. du Toit u. a., „Identifying and managing cow’s milk protein allergy“, Archives of Disease in Childhood - Education and Practice, Bd. 95, Nr. 5, S. 134–144, Sep. 2010, doi: 10.1136/adc.2007.118018.

^[16]      Max Rubner-Institut. Bundesforschungsinstitut für Ernährung und Lebensmittel, „Ergebnisbericht, Teil 2 Nationale Verzehrsstudie II“, S. 307, 2008.

^[17]      „DGE aktualisiert die Referenzwerte für Calcium“. https://www.dge.de/presse/pm/dge-aktualisiert-die-referenzwerte-fuer-calcium/ (zugegriffen März 21, 2018).

^[18]      European Centre for Allergy Research Foundation, „Hühnereiallergie“, ECARF. http://www.ecarf.org/info-portal/allergien/huehnereiallergie/ (zugegriffen März 13, 2018).

^[19]      L. Nachshon u. a., „Decreased bone mineral density in young adult IgE-mediated cow’s milk–allergic patients“, Journal of Allergy and Clinical Immunology, Bd. 134, Nr. 5, S. 1108-1113.e3, Nov. 2014, doi: 10.1016/j.jaci.2014.06.026.

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^[21]      J. S. Kim, A. Nowak-Węgrzyn, S. H. Sicherer, S. Noone, E. L. Moshier, und H. A. Sampson, „Dietary baked milk accelerates the resolution of cow’s milk allergy in children“, Journal of Allergy and Clinical Immunology, Bd. 128, Nr. 1, S. 125-131.e2, Juli 2011, doi: 10.1016/j.jaci.2011.04.036.

^[22]      „Leitlinie_Management_IgE-vermittelter_Nahrungsmittelallergien-S2k-LL_Allergo-Journal_11-2015.pdf“. Zugegriffen: März 16, 2018. ^[Online]. Verfügbar unter: http://www.dgaki.de/wp-content/uploads/2010/05/Leitlinie_Management_IgE-vermittelter_Nahrungsmittelallergien-S2k-LL_Allergo-Journal_11-2015.pdf.

^[23]      'Packaging and labelling: Legal requirements that you have to follow as a food business’, updated 24 March 2021, available at https://www.food.gov.uk/business-guidance/packaging-and-labelling, accessed on 5 July 2021.

^[24]      'Are plant-based milks healthier than dairy?’ BBC, available at https://www.bbc.co.uk/programmes/articles/2SNWxjkWnKNBn6Fzw8Plvyw/are-plant-based-milks-healthier-than-dairy, accessed on 5 July 2021.