Owen, now 7, is allergic to peanuts and tree nuts, said his mother, Haylee Kellogg of Cedar Hills, Utah.

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The recommendations are a U-turn from 2000, when the American Academy of Pediatrics issued guidelines that children should put off having milk until age 1, eggs until 2 and peanuts, shellfish, tree nuts and fish until 3.

WSJ: Food Allergy Advice for Parents: Start Peanuts, Eggs and More Sooner

He is allergic to dairy, peanuts, tree nuts and legumes.

WSJ: Finding Food Allergy Allies

Since 2006, food manufacturers have been required to clearly label products that contain any of the most common allergens -- milk, eggs, fish, shellfish, peanuts, tree nuts, wheat and soy -- but some allergy experts say the labels should be more explicit.

CNN: The story

Common causes include foods such as peanuts, tree nuts, sesame, fish, shellfish, dairy products and eggs.

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