What are food allergies?

Food allergies occur when the body's immune system (the body's own defense mechanism) responds abnormally to certain foods. Usually, the immune system helps the body to fight off harmful things like pathogens. For people with food allergies, the immune system incorrectly identifies certain food components as harmful and produces an inappropriate response. This leads to the unpleasant, and sometimes life-threatening, signs and symptoms associated with allergies.
More than 120 foods are known to cause food allergies. Cow’s milk protein allergy (CMPA), also known as cow’s milk allergy (CMA), is one of the most common food allergies in babies, and usually appears before 1 year of age.
Sometimes CMPA is confused with lactose intolerance, but they are very different: lactose intolerance does not involve the body's immune system. The two share some signs and symptoms, such as stomach and gut problems (like wind and diarrhea). However, while CMPA usually occurs in babies younger than 1 year old, lactose intolerance is very rare in children under 5 years of age.

Globally, the number of babies with food allergies is increasing

The top eight food allergens in children are milk, eggs, fish, shellfish, tree nuts, peanuts, wheat and soybeans. Over the past 10 years, there has been a large increase in the number of babies diagnosed with food allergies.

CMPA usually develops before a baby's first birthday 

Up to 3 out of every 100 of babies will develop CMPA in their first year of life. CMPA is very rare in children older than 6 years of age.

CMPA usually develops before a baby's first birthday 

Up to half of all babies with CMPA will outgrow it after just 1 year, over three quarters will outgrow CMPA after 3 years, and nearly all babies with CMPA will have outgrown it by their

Babies with CMPA should still be breastfed

In rare cases, breastfed babies can develop CMPA by reacting to cow's milk protein in their mother's breast milk. With changes to the mother's diet, breastfeeding can continue safely. This usually requires qualified dietary counselling to completely exclude all sources of cow’s milk protein from the mother’s diet.

Milk allergy in babies

Do not confuse lactose intolerance with CMPA

It is important to know the difference between lactose intolerance and CMPA (also known as CMA), as the two have different causes and also treatments; in addition, CMPA usually develops early in life, whereas lactose intolerance is extremely rare before the age of 5 years.

What is CMPA?

CMPA is a type of milk allergy where a baby's immune system responds to the proteins found in cow's milk, causing the baby to have allergic symptoms. These can include problems with the skin (rash, hives, dry, scaly or itchy skin), digestive system (diarrhea, vomiting, constipation and reflux) and respiratory system (noisy breathing, coughing, runny nose). CMPA usually occurs before a baby’s first birthday.

What is lactose intolerance?

In contrast to CMPA, lactose intolerance does not involve the immune system. Instead, it is the inability to digest the lactose sugar found in cow’s milk, and it is very rare in children younger than 5 years of age. Lactose is one of the most important carbohydrates (sugars) in breast milk and provides many benefits to babies. Lactose helps to promote healthy gut flora and calcium absorption.

CMPA vs. lactose intolerance
Understanding the difference

cmpa diference
Click here to read more about the common signs and symptoms of CMPA


Food allergies are increasing in children: 7 out of every 100 babies are diagnosed with CMPA.
When family members already have an allergy, babies born into the family will have a higher risk of developing an allergy in their lifetime too.
When one parent has an allergy, a baby is twice as likely to develop an allergy than if neither parent has an allergy. However, while presence of allergy in family members can help identify babies with allergy, most babies developing CMPA do not have a known family history of allergy.

CMPA is a food allergy caused by a baby's immune system reacting to proteins in cow's milk. Some babies may develop CMPA after eating or drinking products containing cow’s milk protein, which can cause an immune reaction resulting in allergic symptoms.
There are a few different factors that can help explain why your baby may have CMPA (including inheritance and your baby's particular immune system). However, the reasons for developing CMPA are different for every baby, and there is no need to avoid cow’s milk in your baby’s diet unless your baby is diagnosed with CMPA.

Once CMPA is diagnosed, the symptoms are manageable and feeding your baby will be as smooth and enjoyable as for any parent. It's important to know that CMPA is not a lifelong condition. Up to half of all babies with CMPA will grow out of it after just 1 year, over three quarters will outgrow CMPA after 3 years, and nearly all babies with CMPA will outgrow it by their 6th birthday.

There are different mechanisms behind CMPA, based on how a baby's immune system reacts to cow's milk proteins: IgE-mediated (antibody mediated) and non-IgE-mediated (non-antibody mediated). IgE-mediated symptoms of CMPA can occur within minutes of digesting cow’s milk protein, and normally result in rash (also known as urticaria), swelling of the lips and eyelids, vomiting and wheezing. Symptoms of non-IgE-mediated CMPA usually occur after a couple of hours of digesting cow’s milk protein and usually result in gut and skin-related symptoms. Depending on the observed symptoms and the underlying mechanism, your doctor may decide to perform different diagnostic tests.

Learn more about how CMPA is diagnosed


While the symptoms can be distressing, cow’s milk protein allergy can be easily managed with the correct diet, so getting the right diagnosis from your doctor as early as possible is very important. If you observe any of the symptoms that could be related to CMPA in your baby, firstly, don't worry. Discuss your concerns with your doctor and he/she will follow the steps to reach a final diagnosis. Follow the links below for information and guidance on the CMPA diagnosis path and the common signs and symptoms of CMPA.



CMPA is a food allergy, but symptoms may not only affect the digestive system, they may also involve the respiratory system and the skin.

Learn more about the common signs and symptoms of CMPA



To establish a diagnosis, your doctor will examine your baby and ask about any symptoms you may have noticed. If an allergy to cow’s milk protein is suspected, your doctor can perform specific tests. Once diagnosed, the symptoms of CMPA can be easily managed with expert guidance from your doctor.

Learn more about how CMPA is diagnosed
examined by doc


Would you like some help preparing for your doctor's visit? By printing and completing “My baby's symptom diary,” you can be sure that your doctor will have all the necessary information.

IMPORTANT NOTICE: Mothers should be encouraged to continue breastfeeding even when their babies have cow’s milk protein allergy. This usually requires qualified dietary counseling to completely exclude all sources of cow’s milk protein from the mothers’ diet. If a decision to use a special formula intended for infants is taken, it is important to follow the instructions on the label. Unboiled water, unboiled bottles or incorrect dilution can make babies ill. Incorrect storage, handling, preparation and feeding can eventually lead to adverse effects on the health of babies. Formula for special medical purposes intended for infants must be used under medical supervision.