Milk allergy symptoms


What is a dairy allergy (cow’s milk allergy)?

A milk allergy (also called dairy allergy or cow’s milk allergy) is an adverse immune response to the protein in cow’s milk.

A protein called casein (αs1-, αs2-, β-, and κ-) and whey proteins (α-lactalbumin and β-lactoglobulin) are the major allergens in milk. (1, 2, 3)

Please note that the body may react similarly to the milk proteins from other mammals, such as goat, sheep, buffalo and camel, since they are similar.

It is advisable not to consume other animal’s milk products if allergic to cow’s milk. (4)

Milk allergy is rare in adults and more common in infants. It affects approximately 2.5% of infants in developed countries.

Most infants with a milk allergy develop symptoms within the first month of life and often within 1 week after introducing a formula containing cow’s milk. (5, 3, 6)

Most children outgrow cow’s milk allergy completely by the age of 4 years. However, this process happens at different stages:

  • 1 year of age in up to 50% of children,
  • 2 years of age in up to 75% of children,
  • 3 years of age in up to 90% of children.

The allergy may continue in some cases, but rarely reaches adulthood. (7)

About 75% of the children with cow’s milk allergy can consume baked milk products, such as muffins, cakes or breads, without experiencing any symptoms.

Adding these products to the affected children’s diet, improves tolerance to regular milk products quicker than avoiding them.

The other 25% of children have a more severe type of allergy and a greater chance of severe anaphylaxis to milk. This group experiences allergic reactions to baked milk products.

Milk allergy symptoms (dairy allergy symptoms)

The majority of infants with milk allergy will experience more than two symptoms in more than two organ systems:

  • gastrointestinal (diarrhea, nausea, vomiting);
  • skin (angioderma, dermatitis, eczema, hives);
  • respiratory (asthma, coughing, rhinitis, wheezing). (8)

Different symptoms may occur at different times, depending on the amount of dairy consumed and the severity of the individual’s allergy:

An immediate reaction to a small amount of milk – occurring any time between a few minutes to 2 hours – with the following symptoms:

  • Anaphylaxis is the most severe, life threatening reaction and requires an immediate epinephrine (adrenaline) shot. (5)
  • Abdominal pain and cramps
  • Colic, in babies
  • Coughing
  • Diarrhea or loose stools (may contain blood)
  • Eczema
  • Itchy skin rash around the mouth
  • Hives
  • Swelling of the face
  • Vomiting
  • Watery eyes and runny nose
  • Wheezing

A delayed reaction to a moderate amount of milk – occurring a few hours after – producing the following symptoms:

  • Diarrhea
  • Eczema getting worse
  • Vomiting

A delayed reaction to a normal amount of cow’s milk – after a day or up to a few days – with the following symptoms:

  • Asthma
  • Eczema
  • Diarrhea

Diagnosis of cow’s milk allergy

Milk allergy can easily be misdiagnosed because similar symptoms, unrelated to milk allergy, can occur in 5-15% of cases. (1)

The diagnosis in the case of an immediate reaction that occurs within two hours of consuming milk, is straight forward. It can be done using an allergy skin prick test or blood allergen specific IgE test by your doctor.

You should be aware that, since cow’s milk allergy may result in severe reactions, including anaphylaxis, the allergic food elimination test is not recommended for diagnosis.

Delayed reactions can be difficult to diagnose since the symptoms may be due to various causes and requires a referral from an allergy specialist.

Treatment of cow’s milk allergy

There is no cure for cow’s milk allergy, but the symptoms can be stopped by the complete removal of dairy products from the diet.

Since individuals who are allergic to cow’s milk are also allergic to other dairy products, such as goat’s milk, sheep’s milk and other animal’s milk, a complete avoidance of any dairy products is necessary.

Foods that contain dairy to avoid

The list of foods to avoid includes not only cow’s milk products but other dairy products and other animal’s milk products.

Many processed, packaged, frozen non-dairy products may also contain milk proteins, so it is advisable to carefully search for ingredients on the labels of the foods listed in the image below.


Milk allergy - foods to avoid

You can find the list of foods to avoid on the website of The Australasian Society of Clinical Immunology and Allergy (ASCIA). (9)

Dairy substitute foods

Dairy foods contain high amounts of a wide a variety of nutrients. When eliminating these foods from the diet, other foods of similar nutritional values should take their place in order to avoid deficiencies.

For infants and children, the most important nutrients for their development that are present in milk include: protein, energy nutrients, vitamin D and calcium.

The best substitute for dairy for infants is breast milk or a special formula advised by the doctor.

For children over one year old, products such as soy, rice, oat or nut drinks, soy yogurt, soy cheese, soy sour cream, oil or milk free margarine, soy cream or rice cream may be suitable

For older children, teenagers and adults with milk allergy, the following table shows the list of the most abundant nutrients in milk and the best food sources of each nutrient, ranked by the highest nutrient contents per its usual serving.

Please note that being allergic to milk, you might also be allergic to some of the foods shown in the table.

Before changing your diet, it is best to contact your medical professional to conduct full allergic tests to identify all the other allergens.

Vit B2
Pantothenic Acid
Vit B5
Vit B12CalciumPhosphorusPotassiumSeleniumZinc
White and red meatsBeef liver, cookedBeef liver, cookedClam, cookedPoppy seedsCuttlefish, cookedCoconut waterBrazil nutsOysters
Fish and seafoodCuttlefish, cookedSwordfish, cookedBeef liver, cookedSesame seedsCarp, cookedCuttlefish, cookedOystersBeef, lean
Soybeans, cookedDuck, cookedTuna, cookedOctopus, cookedTurnip greensBeef liver, cookedOctopus, cookedCuttlefish, cookedBeef liver, cooked
Lentils, cookedEgg largeVeal lean, cookedOystersChia seedsPumpkin seedsClam, cookedMussel, cookedLamb lean, cooked
Soy milkMackerel, cookedTrout, cookedMussel, cookedCuttlefish, cookedClam, cookedAdzuki beans, cookedOctopus, cookedCrab, cooked
Pinto beans, cookedClam, cookedBeef, leanMackerel, cookedSpinach, cookedScallops, cookedHalibut, cookedClam, cookedCuttlefish, cooked
Kidney beans, cookedMussel, cookedSalmon, cookedHerring, cookedCollards, cookedSwordfish, cookedAvocadoSwordfish, cookedOctopus, cooked
Black beans, cookedGoose, cookedQuail, cookedTuna, cookedSoy YogurtTuna, cookedPork lean, cookedFlounder, cookedGoose, cooked
Navy beans, cookedLamb lean, cookedPork lean, cookedCrab, cookedPerch, cookedPork lean, cookedLima beans, cookedPerch, cookedVeal lean, cooked
Adzuki beans, cookedPork lean, cookedRabbit, cookedRabbit, cookedDandelion greensChia seedsSnapper, cookedAbalone, cookedQuail, cooked
Lima beans, cookedOystersHalibut, cookedCuttlefish, cookedScallops, cookedGoose, cookedSoybeans, cookedMackerel, cookedTurkey, cooked
Chickpeas, cookedAlmondsMackerel, cookedTrout, cookedOats, cookedHerring, cookedBananaSnapper, cookedScallops, cooked
Pumpkin seedsHerring, cookedChicken breast filetPollock, cookedOctopus, cookedFlounder, cookedScallops, cookedGrouper, cookedLobster, cooked
PeanutsQuail, cookedTurkey, cookedSnapper, cookedCrab, cookedPoppy seedsGrouper, cookedHalibut, cookedClam, cooked
PistachiosChicken breast filetLamb lean, cookedCrayfish, cookedSoybeans, cookedHalibut, cookedPollock, cookedHerring, cookedMussel, cooked
AlmondsTuna, cookedDuck, cookedLobster, cookedClam, cookedMussel, cookedTrout, cookedPollock, cookedDuck, cooked
Sunflower seedsVeal lean, cookedHaddock, cookedLamb lean, cookedTrout, cookedPollock, cookedPinto beans, cookedTuna, cookedPoppy seeds
Spelt, cookedOats, cookedEel, cookedEel, cookedFlaxseedPike, cookedJackfruitPork lean, cookedSesame seeds
FlaxseedSoybeans, cookedPeanutsSalmon, cookedAlmondsOctopus, cookedLentils, cookedLobster, cookedPumpkin seeds
Cashew nutsMushrooms, criminiOats, cookedFlounder, cookedPollock, cookedQuail, cookedCarp, cookedSalmon, cookedRabbit, cooked
Poppy seedsTurkey, cookedHerring, cookedPike, cookedNavy beans, cookedMackerel, cookedKidney beans, cookedHaddock, cookedAdzuki beans, cooked
Sesame seedsSoy milkGoose, cookedSwordfish, cookedHerring, cookedPerch, cookedHerring, cookedCrab, cookedPine Nuts
TofuPollock, cookedPollock, cookedBeef, leanSoy milkOystersNavy beans, cookedShrimp, cookedEel, cooked
Amaranth, cookedBeef, leanOctopus, cookedShrimp, cookedPike, cookedTrout, cookedMackerel, cookedRabbit, cookedChicken breast filet, cooked
Chia seedsRabbit, cookedClam, cookedCarp, cookedAmaranth, cookedSalmon, cookedHaddock, cookedCod, cookedPork lean, cooked

Difference between milk allergy and lactose intolerance

Allergy is an adverse immune reaction to the protein of certain foods. In this case it is an allergy to a milk protein called casein.

Lactose intolerance, on the other hand, is food sensitivity resulting from insufficient enzymes that break-down milk sugars, called lactose, and is of a non-allergenic nature.

While milk allergy affects mostly babies up to four years old and is rare in adults, lactose intolerance affects mostly adults.


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