Between 2 and 3 percent of children younger than 3 are allergic to milk. Although experts once believed that the vast majority of them would outgrow this allergy by the time they turned 3, recent studies contradict this theory. There are two main types of milk protein — casein and whey. Casein, the “solid” part of milk, comprises about 80 percent of milk protein. Whey proteins, found in the liquid part of milk, make up the other 20 percent. Within a short period of time after consuming milk or a milk protein, you may experience the following symptoms:
- Stomach upset
- Bloody stools, especially in infants
Research suggests that some types of milk proteins (casein and two proteins found in whey, alpha-lactalbumin and beta-lactalbumin) are more likely to cause serious reactions. A newer type of blood test, known as a component test, can help the allergist determine your risk for a serious reaction by looking for allergies to those specific proteins. Another test your allergist may order is an oral food challenge.
Management and Treatment:
Avoidance of milk or items containing milk products is the only way to manage a milk allergy. People who are allergic to milk and the parents of children who have this allergy must read ingredient labels very carefully. Most recipes calling for milk can be just as successful by substituting the equivalent in water, juice, or soy or rice milk.