Reviewed by Charles Feng, MD, Board-certified Allergist and Immunologist and Angela Chang, MD, Board-certified Allergist and Immunologist
The key takeaways about food allergen exposure is to start early (i.e., don’t wait) and to expose often. The evidence is strongest for peanut and egg (the most commonly studied allergens), though there is also evidence to support exposure to other common allergens as a means of reducing future allergy risk. In other words, there is evidence for benefits for early allergen exposure for preventing future food allergies, and no evidence of harm.
You may still be wondering, though: How, exactly, should I go about introducing allergens? Do I need to include peanuts in every meal? How many bites does my baby need to consume for the “exposure” to count? What foods can I prepare to incorporate these allergens?
No worries, we totally get it. Below, we’ve summarized the current guidelines for allergen exposure to help provide structure and improve clarity beyond the general “early and often” guidance. Read on!
Introducing an allergen for the first time
- Make sure your baby is developmentally ready for solids (for instance, good head and neck control, showing interest in food) and able to tolerate common weaning foods.
- Make sure your baby is not sick, since cold symptoms can be confused with allergic reactions.
- Start small (for portions) and early (for time of day). Offer your baby ⅛ to ¼ teaspoon of the food and wait 10 minutes to check for an allergic reaction. Starting early in the day gives you more time to observe reactions. If there is no reaction, then continue feeding more.
Main takeaways
- Introduce common allergens after introducing other solids (like carrot, sweet potato, avocado, etc.), so you know that your baby is already tolerating solids well.
- One new allergen every 3 days is a common recommendation. Follow this if it’s helpful, or discuss with your doctor what will work best for you.
- There is no specific order in which you need to introduce new allergens.
- Consistently include the introduced allergens in your baby’s diet to maximize the potential for preventing future allergies! Allergen exposure is an ongoing process.
See the chart below for specific recommendations regarding frequency and amount for different allergens.
Guidelines for including allergens in your baby’s diet
Dairy
(Cow’s milk)
Once a week
1/2 to 1 ounce
If you have not given your baby infant formula yet, start with plain, whole milk yogurt.
Cheese can be given after 6-7 months
No straight cow’s milk until 12+ months
Wheat
Once a week
1/2 to 1 ounce
Infant wheat cereal (iron-fortified) can be a great starting point
Whole-wheat bread, softly cooked pasta (great finger food) or wheat crackers for older babies
Egg
2 to 3 times per week
approx. 1/3 cooked egg
Serve well-cooked egg mashed with pureed foods or chopped and served as finger food
Undercooked egg and raw egg powder are not recommended for children younger than 1 year
Peanut
2 to 3 times per week
2 to 3 teaspoons
Peanut flour or peanut butter (with no added salt, sugar or oil for healthier options)
Peanut butter should be thinned with breast milk, formula, water, yogurt (if no milk allergy), or pureed foods as it can be a choking hazard in infancy.
Bamba, a puffed corn snack made with peanuts, is also an option. Bamba can be softened with water, breast milk, or formula.
Tree nuts
once a week
1 to 3 teaspoons
Introduce each nut individually.
Nut powder or nut butter can be thinned with breast milk, formula, water, yogurt, or pureed foods.
Tree nuts include:
- Almond
- Walnut
- Pecan
- Pistachio
- Cashew
- Hazelnut (Filbert)
- Brazil nut
- Macadamia nut
- Pine nut
Sesame
1 to 2 times per week
1 teaspoon
Tahini (sesame paste) or hummus with tahini, or crushed sesame seeds
(Note: The sesame protein is the allergenic compound. Sesame oil contains very little protein so it’s not a very effective way of exposing the baby to the sesame allergen)
Fish (finned fish)
every 1 to 2 weeks
1 oz
Cook well-done and flake (or cut into small pieces).
Shellfish
every 1 to 2 weeks
1 oz
Cook well-done and cut into small pieces. Shrimp is typically recommended in the baby’s first year to cover shellfish exposure.
Soy
2 to 3 times per week
2 to 3 teaspoons
Soft or silken tofu, edamame, soy milk, or soy yogurt
(Note: There is not much protein in soy sauce, and the salt content is very high so it’s not a very effective way of getting soy exposure)
