When Might My Child Outgrow His Milk Allergy?

When will you child outgrow milk allergy?. Daniel More, MD

When Might My Child Outgrow His Milk Allergy?

Cow’s milk allergy is the most common food allergy occurring in young children, affecting up to 3% of kids. Previous studies have shown that most children, up to 80%, will outgrow milk allergy by 3 to 5 years of age. That means that a significant proportion of children will continue to be allergic to milk, at least until their adolescent or teenager years, and may never outgrow their milk allergy.

Is it Really a Milk Allergy?

Your pediatrician may mention the term "allergy" without offering clarification that may help you get a better handle on exactly what your child is facing.

True allergy to milk involves the presence of allergic antibodies, or IgE, against various proteins in milk. The diagnosis is made with a positive allergy test to milk.

But non-allergic reactions to milk can also occur in children. These are identified by the absence of allergic antibody and a negative allergy testing result. Food protein-induced enterocolitis syndrome (FPIES) and lactose intolerance are examples of non-allergic reactions. FPIES typically occurs in young infants, and is commonly outgrown by age 3. Lactose intolerance, on the other hand, typically occurs in older children and adults and is less likely to be outgrown.

Outgrowing Milk Allergy

A more recent large study of over 800 children with milk allergy showed that outgrowing milk allergy may not be as common as previously thought.

This study showed that children with allergic rhinitis, asthma or other common food allergies were less likely to outgrow milk allergy. In addition, children with milk allergy who ever received baby formula during infancy were also less likely to outgrow milk allergy.

Based on the most accurate definition of outgrowing milk allergy in this study, the percentages of previously allergic children who could tolerate milk at various ages were:

  • 19% by age 4
  • 42% by age 8
  • 64% by age 12
  • 79% by age 16

The most helpful predictor of outgrowing milk allergy was the level of allergic antibody to milk measured in the blood. This is determined by a RAST, with a level of around 2 kU/L (kiliunits per liter) or less being most predictive of having outgrown milk allergy. Most allergists find that following the allergic RAST antibody level to milk is very helpful in determining when a child may have outgrown a milk allergy and when he may be ready for an oral food challenge under medical supervision. Unfortunately, some children may never outgrow their milk allergy, and their food allergy may persist into adulthood, or even indefinitely.

Want to learn more? Find out about:


Skripak JM, Matsui EC, Mudd K, Wood RA. The Natural History of IgE-Mediated Cow’s Milk Allergy. 2007; 120:1172-7.

Continue Reading