Guidance on allergenic foods has shifted in recent years — rather than delaying them, introducing foods like egg and peanut earlier is now understood to help prevent food allergies in many babies.
When to Start
Allergenic foods such as egg, peanut, dairy, and fish are recommended for introduction around 4 to 6 months of age, once a baby is ready to start solids. Even babies at higher risk for food allergy — such as those with a sibling or parent with allergies — are not advised to delay these foods.
How to Introduce Them
Offering one new allergenic food at a time, in a small amount, and waiting a few days before trying the next is a commonly suggested approach. Well-cooked egg or a thin layer of peanut butter mixed into cereal or purée are easy-to-swallow starting forms.
Watching for a Reaction
After trying a new food, it’s worth watching for hives, a rash around the mouth, vomiting, or diarrhea. If no reaction shows up, continuing to include the food regularly in the diet is thought to help maintain tolerance over time.
When to Seek Care Right Away
Rapid swelling around the lips or eyes, hives across the body with repeated vomiting, or wheezing and difficulty breathing after a new food can signal anaphylaxis and call for immediate emergency care. This information is based on U.S. (AAP) guidance; if you live elsewhere, check with a local pediatric provider for country-specific recommendations. This information isn’t a diagnostic tool and doesn’t replace advice from a medical professional.