Peanut Allergy Prevention: When and How to Introduce Peanuts to Infants

For years, parents were told to wait until their child was two or three before introducing peanuts. It seemed like the safest move-until it wasn’t. By 2010, peanut allergies in U.S. children had more than quadrupled since 1997, jumping from 0.4% to 2.0%. Hospitals saw more emergency visits from kids having life-threatening reactions than ever before. Then came the LEAP study, a landmark trial that flipped everything we thought we knew about peanut allergies on its head. The result? A new standard of care that’s now preventing thousands of cases every year.

Why Early Introduction Works

The old advice-delay peanut exposure-was based on fear, not science. But research showed that avoiding peanuts didn’t protect kids. It made them more likely to develop allergies. The key insight from the LEAP study was simple: the immune system learns what’s safe by encountering it early. When babies are exposed to peanut protein between 4 and 6 months, especially if they’re at risk, their bodies learn to tolerate it instead of attacking it.

This isn’t just theory. The LEAP trial followed over 600 high-risk infants-those with severe eczema or egg allergy-and found that those who ate peanut products regularly from 4 to 6 months had an 86% lower chance of developing peanut allergy by age 5. The numbers don’t lie: if you introduce peanut early, you’re not just reducing risk-you’re cutting it nearly in half.

Follow-up studies confirmed it. The EAT study, which looked at early introduction of multiple allergens including peanut and egg, showed similar results. When you combine data from both trials, the reduction in peanut allergy jumps to 75-98%, depending on how strictly families followed the plan. The magic window? Before 6 months. The earlier you start, the stronger the protection.

Who Needs to Introduce Peanuts Early?

Not all babies need the same approach. The National Institute of Allergy and Infectious Diseases (NIAID) broke it down into three clear risk groups:

• High-risk infants: Those with severe eczema, egg allergy, or both. These babies should be evaluated by a doctor or allergist between 4 and 6 months. If allergy tests come back negative, they can start eating peanut protein at home-after a supervised first dose in the clinic.
• Moderate-risk infants: Those with mild to moderate eczema. No testing needed. Just start introducing peanut around 6 months, at home, like any other solid food.
• Low-risk infants: No eczema, no food allergies. Introduce peanut anytime after starting solids, usually around 6 months. No special steps needed.

It’s important to get this right. A 2023 survey found that only 54% of pediatricians could correctly identify the current guidelines. That means many parents are still getting outdated advice. Don’t rely on guesswork. Check the NIAID guidelines. Talk to your doctor. This isn’t a one-size-fits-all situation.

How to Safely Introduce Peanut

Never give whole peanuts or chunky peanut butter to babies. They’re choking hazards. Instead, use smooth peanut butter, peanut powder, or specially designed infant peanut products.

Here’s how to do it safely:

1. For high-risk babies: First, get tested. If the skin prick or blood test is negative, prepare a small amount of peanut protein-2 grams, which equals about 2 teaspoons of smooth peanut butter mixed with 2-3 tablespoons of warm water, breast milk, or formula.
2. Offer the first taste during a time when you can watch your baby closely-like mid-morning on a weekday. Don’t try it for the first time before bed or while traveling.
3. Wait 10 minutes. Watch for swelling, hives, vomiting, or trouble breathing. If anything looks off, stop and call your doctor.
4. If there’s no reaction, give the rest of the dose. Then, keep feeding peanut protein three times a week, every week, for months.

For moderate and low-risk babies, skip the testing. Just mix peanut butter into pureed fruits, oatmeal, or yogurt. Start with a small spoonful and build up. The goal is consistency, not speed. You’re not trying to overwhelm the system-you’re training it.

Products like Bamba (a crunchy peanut snack) or spoonable peanut butter pouches are now widely available. They’re designed for babies, easy to digest, and safe. Some parents even use peanut flour mixed into baby cereal. The key is to get 2 grams of peanut protein per serving, three times a week.

What About Oral Immunotherapy (OIT)?

Oral immunotherapy (OIT) is not the same as early introduction. OIT is a treatment for kids who already have a peanut allergy. It involves slowly increasing doses of peanut protein under medical supervision to build tolerance. It’s not a prevention strategy-it’s a management plan.

Some families with diagnosed peanut allergies use OIT to reduce the risk of severe reactions from accidental exposure. But it’s not a cure. Kids still need to avoid peanuts, and reactions can happen during treatment. It’s also expensive, time-consuming, and requires regular clinic visits.

Early introduction, on the other hand, is free, simple, and done at home. It prevents the allergy from forming in the first place. That’s why experts say prevention is better than treatment. If your child doesn’t have an allergy yet, early introduction is the best tool you have.

Why So Many Parents Still Wait

Even with strong evidence, only about 39% of high-risk infants are getting peanut introduced on time. Why? Fear.

Parents worry about choking. They worry about anaphylaxis. They worry their pediatrician didn’t tell them what to do. A 2022 survey found that 62% of parents felt anxious about introducing peanut. And many doctors didn’t bring it up.

There’s also confusion about what counts as “peanut.” Some think peanut butter is too thick. Others try peanut oil, which doesn’t contain the proteins that trigger allergies. Or they use crunchy peanut butter, which is dangerous. The right form matters.

And there’s a deeper problem: disparities. Black and Hispanic infants are 22% less likely to get early peanut exposure than white infants. That’s not because of cultural preferences-it’s because of access. Fewer doctors in these communities are trained on the guidelines. Fewer clinics offer testing. Fewer stores stock infant-safe peanut products.

What’s Changed Since 2017?

Since the NIAID guidelines came out in 2017, peanut allergy rates have started to drop. The CDC reports a decline from 2.2% in 2015 to 1.6% in 2023. That’s about 300,000 fewer children with peanut allergies in the U.S. alone.

The biggest drops? In kids with eczema. Mild eczema: 85% fewer allergies. Moderate eczema: 87% fewer. Even severe eczema saw a 67% reduction. That’s huge. And it’s not just peanuts-when families start early with multiple allergens like egg and milk, they see lower rates of multiple food allergies too.

Long-term data from the LEAP study shows the protection lasts. Kids who ate peanut early and then stopped for a year still didn’t develop allergies. That suggests true immune tolerance-not just temporary desensitization.

What’s Next?

Researchers are now looking at how to make early introduction even better. The PRESTO trial, funded by the NIAID and expected to finish in 2026, is testing whether giving peanut protein even earlier-around 3 months-works better for the highest-risk babies.

Other studies are exploring whether combining early peanut introduction with skin barrier repair (like using moisturizers for eczema) can boost results. There’s also work on making peanut products more affordable and accessible in underserved communities.

But the biggest challenge isn’t science anymore. It’s implementation. We know what works. Now we need every parent, every pediatrician, every clinic to do it.

What Parents Should Do Now

Here’s your action plan:

• If your baby has severe eczema or egg allergy: Talk to your pediatrician by 3-4 months. Ask about referral to an allergist for testing.
• If your baby has mild to moderate eczema: Start introducing peanut around 6 months. Use smooth peanut butter or a peanut powder mixed into food.
• If your baby has no eczema or allergies: Just add peanut when you start solids-no need to wait.
• Always use smooth peanut butter, not chunky. Never whole peanuts.
• Give peanut protein three times a week, consistently. Missing doses reduces the benefit.
• Don’t wait for symptoms. Prevention only works before the allergy develops.

This isn’t about being perfect. It’s about being consistent. Even if you start at 7 months instead of 5, you’re still helping. But the earlier, the better.