Allergies to peanuts, nuts, shellfish, or fish are usually lifelong.
Thankfully, infants who are allergic to cow's milk usually do outgrow this. Many will be allergy-free by their first birthdays. The great majority will have no more symptoms by age 3.
Those few that are still allergic after 3 can often still lose their sensitivity -- if they are not exposed to cow's milk for 1 to 2 years.
Of note, at least 30% of kids with cow's milk allergy are also allergic to soy. Soy allergies are outgrown at about the same pace as milk allergies.
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