Cow's milk allergy (CMA) is a food allergy resulting from the infant's immune system reacting to proteins found in cow's milk as if they are foreign substances. The allergy is particularly pronounced during infancy, when the intestinal wall is not yet fully developed. CMA, which can also appear in breastfed babies, is not solely a problem associated with formula consumption; because milk and dairy products consumed by the mother can be transferred to the baby through breast milk. Therefore, cow's milk allergy is a condition that should be carefully evaluated in both breastfed and formula-fed infants.
What is Cow's Milk Allergy (CMA)?
Cow's milk allergy is triggered when the infant's immune system perceives the proteins found in cow's milk as harmful substances and reacts. The allergic reaction can be triggered not only by direct consumption of cow's milk but also by consuming foods containing milk such as yogurt, cheese, butter, or even if the mother includes dairy products in her diet.
CMA can manifest symptoms in infants in the digestive system, skin, and respiratory tract. Some symptoms appear very quickly, while others develop slowly over days and may not be immediately recognized by parents.
What are the Symptoms of Cow's Milk Allergy in Infants?
The symptoms of cow's milk allergy vary in each infant. In some, reactions develop very rapidly, while in others, symptoms may appear more slowly and be mistaken for colic or normal baby behavior over an extended period.
Sudden Onset Symptoms
These may appear within the first hours after consuming a milk-containing food:
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Sudden redness and swelling of the skin
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Swelling around lips, tongue, or eyes
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Severe and repeated vomiting
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Difficulty breathing
Delayed and Deceptive Symptoms
Symptoms can start mildly and become more pronounced over time:
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Inconsolable restlessness and prolonged crying spells
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Frequent and persistent reflux
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Blood and mucus in stools
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Frequent diarrhea or conversely, constipation
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Uncontrolled eczema and skin dryness
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Post-feeding discomfort and abdominal pain
What Causes Cow's Milk Allergy?
Under normal circumstances, the digestive system can break down these proteins and tolerate them, but in babies with allergies, the immune system develops an exaggerated sensitivity to these proteins. This situation can develop due to a combination of genetic and various environmental factors.
The underdeveloped state of the digestive system in infants can allow milk proteins to enter the bloodstream intact, which is perceived as a threat by the immune system, triggering an allergic reaction.
Having a family history of food allergies is also among the factors that increase the risk of developing cow's milk allergy. Early initiation of formula feeding or early introduction of dairy products during the complementary feeding period can also trigger allergic reactions in some babies.
What Foods Cause Cow's Milk Allergy?
The primary cause of cow's milk allergy is the proteins found in cow's milk. Thus, not only milk but also many foods prepared with dairy derivatives can lead to allergic reactions.
There are two main groups of proteins in cow's milk that cause allergies:
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Casein
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Whey proteins
Any food containing these proteins holds the potential to trigger cow's milk allergy.
Common Foods Containing Cow's Milk
The following foods, which contain milk directly, can cause reactions:
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Milk
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Yogurt
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Cheese
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Butter
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Cream
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Ice cream
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Buttermilk
Processed Foods Containing Milk Products
Some foods might not seem to contain milk, but they may include milk protein. Therefore, ingredient labels should be carefully read:
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Packaged cookies and cakes
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Chocolates and cocoa snacks
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Instant soups
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Breakfast cereals
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Crackers and biscuits
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Types of margarine
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Sauces
Labels Indicating Milk Content
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Casein
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Caseinate
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Whey powder
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Lactoalbumin
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Milk protein
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Milk derivative
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Lactoferrin
Any of these terms indicate that the product contains milk protein.
Indirect Effect in Breastfed Babies
Breastfed infants may receive milk and dairy products consumed by the mother in small amounts through breast milk. Therefore, the mother's consumption of foods containing milk can trigger allergic reactions.
Beware of Plant-Based Milk Alternatives
Plant-based milks like soy milk, almond milk, or oat milk do not contain milk protein; however, some packaged products might have a risk of cross-contamination. Therefore, label information should be checked.
How is Cow's Milk Allergy Diagnosed?
The diagnosis of CMA starts with evaluating the infant's feeding history and symptoms. The following methods are generally used in diagnosis:
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Elimination diet: Complete removal of milk and dairy products
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Observation: Evaluating whether symptoms decrease
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Challenge test: Controlled re-introduction to confirm allergy
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Allergy testing when necessary
How is Cow's Milk Allergy Treated?
The primary goal of treating cow's milk allergy is to minimize the infant's contact with milk proteins to control allergic symptoms. The treatment approach is planned based on the infant's feeding pattern, and the process should be monitored as each infant's needs may differ.
- In breastfed infants
In such cases, treatment begins with the mother avoiding milk and dairy products in her diet. By excluding all milk-derived foods from her diet for a specific period, the mother can reduce the infant's exposure to allergens. It is essential that the mother continues to have sufficient and balanced nutrition during this period.
- In formula-fed infants
For infants using formula, standard cow's milk-based formulas are not suitable. Instead, extensively hydrolyzed formulas, where milk proteins are broken down through special processes, or amino acid-based formulas can be preferred if the allergy is more pronounced.
Throughout the treatment process, the infant's growth and development should be regularly monitored. Most infants may start to develop tolerance to milk proteins between the ages of 1–3 as their immune systems mature. However, controlled medical follow-up is necessary to assess whether the allergy has completely resolved.
Frequently Asked Questions
How long does cow's milk allergy last?
As infants' immune systems mature, they may begin to develop tolerance to milk proteins between the ages of 1–3.
Can cow's milk allergy occur in breastfed babies?
Yes, cow's milk allergy can occur in breastfed babies. This is due to the trace amounts of milk proteins from dairy products consumed by the mother that can pass into breast milk.
Is cow's milk allergy the same as lactose intolerance?
No, these are entirely different conditions. Cow's milk allergy involves the immune system, while lactose intolerance can result from a deficiency in digestive enzymes.
Can milk be consumed again after cow's milk allergy resolves?
Once the allergy resolves, milk and dairy products can be reintroduced under medical supervision. However, this trial should only be undertaken following medical evaluation.
