Parents should introduce common allergy-causing foods like peanuts, eggs, wheat, tree nuts, and shellfish as soon as your baby can eat food. For most babies, this is between 4 and 6 months old, when they can sit up with assistance and hold their necks steady. 

Doctors recommend practicing early introduction with most allergy-causing foods to reduce the risk of food allergy. 

While early introduction can help protect against food allergies, there’s no research to suggest feeding your baby allergenic proteins before they start eating solid food has additional benefit. 

If you’ve got an early eater, great! Feel free to start adding baby-safe forms of nuts, eggs, and wheat to their meals. But the American Academy of Pediatrics says that food or food protein should never be added to a bottle of breastmilk or formula

So really, you can start feeding your baby common allergens once they start eating other solid food.

What to Feed Baby First?

There is no correct order for starting new foods, and you do not have to wait between new foods (most allergic reactions happen within 4 hours of eating a food). Peanuts and tree nuts should be introduced, in a baby-safe form, as soon as they are able to swallow runny foods. 

Many babies start eating with a pureed fruit or vegetable. Once your baby has shown that they can swallow one food texture, they can swallow any food in the same texture. 

Another common first is baby cereal made of wheat. In 2020, adding wheat into a baby’s diet with wheat cereal was proven to reduce the risk of wheat allergy and celiac disease.

There is a special exception to the 4-6 months old rule for introducing allergens — milk. Most formulas in the United States are made from cow’s milk, so they already contain enough exposure to milk protein. Feeding babies a little bit of formula along with breastmilk from 2 weeks old has been proven to prevent milk allergy and a related disease called FPIES

Drinking both breastmilk and formula is better than all formula or all breastfeeding! 

Note: If your baby is not drinking formula, do not feed them pure cow’s milk. Baby formula changes and fortifies cow’s milk so that it is digestible and has the proper nutrients.

Scared to Add Allergens Into Food?

If your baby has severe eczema or a known food allergy, you may want to talk to your doctor before starting other solid foods. Your doctor should tell you to start as many foods as possible as soon as possible to begin training your baby’s immune system to recognize new food as safe. 

If you aren’t scared of feeding your baby applesauce or mashed banana, you shouldn’t be scared of feeding peanuts, tree nuts, or eggs either — as long as they are prepared correctly. 

Remember, the safest time to start adding common allergens to your baby’s diet is when they are very young. This will train their immune system before it can make mistakes and before they have serious symptoms.