Cow’s milk allergy (CMA) occurs when the body’s immune system mistakenly reacts to proteins found in milk. In the UK, CMA affects 2-3% of babies and young children, with most growing out of it by the age of five. Immediate milk allergy is uncommon in adults. What is cow’s milk allergy?
Allergic reactions can be immediate or delayed.
Immediate allergy symptoms may include itchy rash, redness or hives (nettle rash), swelling, runny nose, itchy eyes, coughing, vomiting, swallowing or breathing difficulties (rare).
Delayed allergy symptoms may include diarrhoea, constipation, reflux, profuse vomiting, mucous / blood in stools, nausea, abdominal (tummy) pain, bloating, painful wind, eczema.
If you think you or your baby are reacting to milk, get expert medical advice. Many of the above symptoms are also common in babies who do not have CMA.
Diagnosis involves your GP undertaking an allergy history and physical examination. If you or your baby have immediate allergy symptoms, they may refer you for allergy testing. For delayed allergy symptoms they could ask you to do a milk exclusion trial followed by reintroduction.
Cow’s milk allergy is not the same as lactose intolerance. For more information about the differences between food allergy and intolerance view our food fact sheet. How can a dietitian help?
A dietitian can help you make sure your diet gives you all the nutrients you need while avoiding the cow’s milk that you or your baby are allergic to. How can I eat with this in mind? Breastfeeding Until around the age of six months, human or formula milk should be an infant’s sole source of nutrition. If you are solely breastfeeding and your baby develops CMA, you may need to avoid cow's milk in your own diet. Infant formula If CMA symptoms start after introducing cow's milk formula or dairy products, you can still have cow's milk in your diet. If you use infant formula - either for all feeds or to supplement breastfeeding - you should seek expert advice. They will prescribe a suitable hypoallergenic (low allergy) formula for babies with CMA.
A soy-based formula may be a suitable alternative if the baby is able to tolerate it. This should not be given to infants under six months old.
Lactose free cow’s milk is not suitable for CMA as it still contains cow’s milk proteins. Avoid animal milks such as sheep and goat’s milk as they have similar proteins to cow’s milk, so may also trigger symptoms. Plant-based milk alternatives You should not use plant-based milk alternatives, like oat, coconut and almond, as a main drink until at least 12 months of age. These products do not provide enough energy, protein or micronutrients to support optimal growth and development in infants.
You can use them in cooking for infants over six months of age.
You should not give rice milk to infants under four-and-a-half years of age due to risk of inorganic arsenic. Introducing solid foods You can introduce milk-free foods around six months of age, when your baby is ready. Try to include all foods in the diet before one year of age. This includes egg and peanuts in an infant safe form e.g. peanut butter, mashed/pureed hard-boiled egg). A dietitian's advice is crucial throughout this process to support growth and integration into family meals. Food labels
Cow’s milk products such as milk, cheese or yoghurt are easily identifiable on labels, but cow’s milk is often added to manufactured foods. Always read food ingredient labels carefully every time, as ingredients may change.
By law labels must state whether cow's milk (and other common allergens) is present in a food product. Look for the word milk in bold in the ingredients label (see below).
Olive spread (margarine)
Ingredients: Vegetable oils (including olive oil (22%), water, whey powder (milk), salt (1.3%), stabiliser (sodium alginate), emulsifier (mono and diglycerides of fatty acids), lactic acid, natural flavouring, vitamins A and D, colour (carotenes).
For allergens, see ingredients highlighted in bold.
Some people react to very small amounts of cow’s milk in food, while others can tolerate it in baked or cooked foods e.g. biscuits or pancakes.
‘May contain milk’ statements are often used on food packaging to state that a food may be contaminated with cow’s milk, but there is no law requiring this. Avoiding these can be overly restrictive, but may be recommended if you have severe symptoms. Discuss the safest approach with your dietitian.
The Food Maestro app is a useful tool to help you find ‘cow’s milk free’ products. Features include filtering products by ingredients you want to avoid, scanning products to check they are suitable and creating personal shopping lists. Milk free diet top tips
Meal Replacement Plain soya, oat or coconut-based yoghurts, coconut milk or oat cream / Curries, raita, stroganoffs, creamy sauces and dips crème fraiche. Pizza, cheese on toast or lasagne Milk-free melting cheese Dips, cheesecakes and other savoury and sweet Milk-free soft of spreading cheese or dairy-free sour cream sauces
Alternative milk free foods Plant-based drinks such as oat, soya, pea, coconut, flaxseed, sesame, quinoa, nut (almond, hazelnut, cashew) and rice (if over four-and-a-half years age) Milk-free spreads or margarine Plant-based cheeses, yogurts, creams, crème fraiche, desserts, ice creams, frozen desserts based on a range of soya, pea, oat, cashew, almond, rice or coconut Alternative sources of vitamins and minerals Choose alternatives to milk, yoghurt and cheese that are fortified with calcium. Many now contain as much calcium as you would find in cow’s milk. Ask your dietitian for advice on calcium and vitamin D requirements, and whether you need supplements.
Try to include iodine-rich foods in the diet such as fish and eggs. Some plant-based milks and yoghurts contain added iodine as well as calcium and vitamins B2 and B12. Eating out with a milk allergy
Always ask about ingredients and inform staff about allergy requirements. The law does not require written ingredients labels on pre-packed for direct sale foods sold in outlets such as bakeries and takeaways. Allergen advice can be given verbally or on a menu. As of 1 October 2021 the law requires these foods to have written labels with a full ingredients list and highlighted allergens. Travelling with a milk allergy If you are travelling abroad, check in advance how to describe you or your child's allergies in the local language. See the Useful Resources for websites that provide useful phrases and eating out translation cards.
Speak to your airline well in advance to ensure they can meet you or your child’s dietary needs. Ask your doctor or dietitian for a letter to support you taking food items or hypoallergenic formula on the flight.
Most children outgrow CMA - your dietitian can guide you on how to gradually reintroduce foods containing milk. Your doctor or dietitian can advise whether your child may need to have a milk challenge in hospital first or to follow a ‘milk ladder’ at home. Top tips
If you think you or your child may have CMA, make a note of symptoms related to the upper and lower gut, skin and breathing. Note how quickly they occur after having cow’s milk and seek advice from your GP Severe CMA is rare but the following symptoms within minutes to two hours after consuming cow’s milk could suggest an immediate severe or anaphylactic reaction: swollen tongue, hoarse voice, difficulty swallowing or breathing, wheezing, a persistent cough, faintness, drowsiness, dizziness, a weak and floppy appearance. Use adrenaline if this has been prescribed, call 999 and state ‘anaphylaxis’ Carry antihistamines and any other medications prescribed to manage you or your child’s allergy at all times If CMA is diagnosed, your GP or an allergy clinic can make a referral to a registered dietitian Read food labels every time, as ingredients can and do change Change family meals and snacks to make them milk free, to help your child feel more included If someone is looking after or feeding your child, make sure they are aware of dietary requirements to prevent mistakes