By Kristen Criscitelli MS, RDN/LDN, CDN, CLC
Pregnancy & Breastfeeding
Can you prevent food allergies during pregnancy or lactation? The short answer is no.
Current research shows that avoiding specific foods during pregnancy or breastfeeding does not
prevent food allergies in your baby and is not recommended. In fact, unnecessary food
restrictions can increase the risk of nutritional deficiencies without any clear benefit and can
even increase risk of inadequate weight gain during pregnancy. Plus elimination can add a layer
of stress that isn’t needed.
Although research is needed to make any firm recommendations, mom’s diet during pregnancy
and lactation that are higher in fruits and veggies, fish, and full fat dairy have been shown to be
helpful in reducing overall allergy risk and the Mediterranean-style pattern is associated with
lower risk of food allergy risk in children. So the take aways here are to:
● Eating a varied, balanced diet with fruits, vegetables, whole grains, and healthy fats
● Maintaining good nutrition overall, rather than eliminating foods
Good news if you love peanut butter though. If you’re breastfeeding, emerging research
suggests that eating peanuts yourself while also introducing peanuts to your baby before age 1
may help reduce the risk of peanut allergy, but more research is needed before making this a
universal recommendation.
What about supplements?
The evidence is limited but here’s what the research shows:
There is no specific vitamin or supplement proven to prevent food allergies, but there is some
research that shows vitamin D and omega 3s can be helpful. Since the evidence is still evolving,
routine supplementation isn’t recommended.
However, if you’re pregnant, those are two nutrients that are really important to make sure
you’re getting enough (regardless of allergy prevention).
○ Aim for at least 600 IU daily of Vitamin D. Some evidence shows up to 4,000 IU
may be beneficial.
○ An international consensus recommends at least 200 mg DHA daily for pregnant
women. But, higher doses of 600-1000 mg DHA daily may provide additional
benefits.
There is some research to show that probiotic supplementation during late pregnancy can
reduce the risk of eczema, but there is no evidence for reduced risk of food allergies.
Other important steps that may influence allergies:
● Avoid cigarette smoke exposure
● Keep asthma and allergies well-managed during pregnancy
Infancy & Early Childhood
Can you reduce your baby’s risk of food allergies when starting solids? Yes! Here is where we
have the strongest evidence.
Breastfeed for about 6 months, if it works for you and your baby
● If you are not breastfeeding, standard formula is appropriate. Contrary to what some
people say, special formulas are not needed for allergy prevention.
● Introduce allergenic foods early, once your baby is ready for solids (around 6 months)
There are 9 common allergens which are important for early introduction. They include:
Milk, egg, peanut, tree nuts, soy, wheat, finned fish, shellfish, and sesame
Research shows:
● Peanut introduction between 4–11 months can reduce peanut allergy risk
● Egg introduction around 6 months may reduce egg allergy risk
Something that is important to keep in mind is that once the allergen is introduced, it’s important
to continue offering these foods regularly to help maintain tolerance.
When giving a new allergen, here are some things to keep in mind:
● Introduce the allergen early in the day so you can monitor for a reaction. Reactions
typically occur immediately after but can happen up to 2 hours after.
● Your baby may not have a reaction on the first trial. Sometimes the 2nd or 3rd time is
when a reaction will occur.
● Don’t introduce more than one allergen in a day.
Lastly, supporting a healthy gut
A diverse, well-fed gut microbiome may play a role in reducing allergy risk. You can support this
by:
● Offering fiber-rich foods (whole grains, legumes, fruits, vegetables)
● Including fermentable fibers like bananas, onions, garlic, asparagus, and cooked/cooled
potatoes or rice
● Serving a wide variety of plant foods
● Continuing breastmilk when possible
● Encouraging outdoor play, which supports microbiome diversity
A Note on Eczema
The relationship between eczema and food allergies is complex. Babies with early, severe
eczema are at higher risk for developing food allergies. However, avoiding foods without a
confirmed allergy can actually increase risk. If your baby has eczema, talk to your doctor (and
dietitian!) for guidance.
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