For years, parents were told to wait until their child was two or three before giving them peanut butter. It seemed like a safe choice-until the numbers started climbing. By 2010, peanut allergies in U.S. children had jumped from 0.4% to 2.0%. Emergency rooms were filling up with kids having reactions, and families lived in fear of accidental exposure. Then came the LEAP study, a groundbreaking trial published in 2015, that flipped everything on its head. It didn’t just challenge old advice-it proved that waiting was making things worse.
Why Early Introduction Works
The key insight from the LEAP study was simple: exposing a baby’s immune system to peanut protein early, while it’s still learning what’s safe, can train it to tolerate the food instead of attacking it. The study followed over 600 high-risk infants-those with severe eczema or egg allergy-and split them into two groups. One group avoided peanut entirely until age five. The other started eating peanut-containing foods as early as four months, three times a week. By age five, only 1.9% of the group that ate peanut developed an allergy. In the avoidance group? 13.7%. That’s a 86% reduction.
Follow-up studies like EAT (Enquiring About Tolerance) confirmed it. When peanut was introduced before six months, the risk dropped even further. In babies with mild or moderate eczema, the reduction hit nearly 100% in those who stuck to the plan. The window isn’t wide-4 to 6 months is the sweet spot. After six months, the protective effect starts to fade. And before four months? Too early. Babies need to be developmentally ready for solids: able to sit up, hold their head steady, and show interest in food.
How to Introduce Peanut Safely
Not all peanut products are safe for babies. Whole peanuts? Choking hazard. Chunky peanut butter? Same issue. The goal is smooth, thin, and easy to swallow. The standard dose is 2 grams of peanut protein-roughly two teaspoons of smooth peanut butter-given three times a week. Here’s how to do it right:
- Thoroughly mix 2 teaspoons of smooth peanut butter with 2-3 tablespoons of warm water, breast milk, or formula until it’s a thin, runny paste.
- Stir it into baby cereal, mashed banana, or pureed sweet potato.
- Start with a tiny amount-like a quarter of a teaspoon-on the tip of a spoon. Wait 10 minutes. Watch for swelling, hives, vomiting, or breathing trouble.
- If no reaction, give the rest. Continue this three times a week, even if they love it or seem indifferent.
Some parents use products like Bamba, a puffed corn snack with peanut, which dissolves easily in the mouth. Others use powdered peanut protein mixed into formula. The method doesn’t matter as long as the protein dose is consistent and the texture is safe.
Who Needs Medical Supervision?
Not every baby needs to see a doctor before trying peanut. But some do. The current guidelines divide babies into three risk groups:
- High-risk: Severe eczema or egg allergy. These babies should be evaluated by a pediatrician or allergist between 4-6 months. Testing (skin prick or blood) may be done first. If results are negative, the first peanut dose is often given in the doctor’s office.
- Moderate-risk: Mild to moderate eczema. No testing needed. Introduce peanut at home around 6 months, following the same steps above.
- Low-risk: No eczema or food allergies. Introduce peanut anytime after starting solids-usually around 6 months-just like any other new food.
Even if your baby is low-risk, don’t wait. The benefits are strongest when peanut is introduced early. Delaying doesn’t protect-it increases risk.
What About Oral Immunotherapy (OIT)?
Oral immunotherapy (OIT) is not prevention. It’s treatment-for kids who already have a peanut allergy. OIT involves giving tiny, gradually increasing doses of peanut protein under medical supervision to build tolerance. It’s not for healthy babies. It’s not for families looking to prevent allergy. It’s for those already living with it.
Studies show OIT can help kids tolerate small amounts of peanut without a reaction-enough to avoid emergencies from accidental exposure. But it’s not a cure. Most kids still need to avoid peanut long-term. Side effects like stomach pain, vomiting, or itchy skin are common. And if you stop the daily dose, tolerance often fades.
Prevention through early introduction is far safer, simpler, and more effective. Why treat a problem you can prevent?
Why So Many Parents Still Wait
Despite clear guidelines, only about 39% of high-risk infants in the U.S. get peanut introduced on time. Why? Fear. Confusion. Lack of clear advice from doctors.
A 2022 survey found 62% of parents were anxious about giving peanut to their baby. Many didn’t know how much to give. Others were told by their pediatrician to wait. A 2023 study showed only 54% of pediatricians correctly remembered the current guidelines.
There’s also a gap in access. Black and Hispanic infants are 22% less likely to get peanut early than White infants. This isn’t just about education-it’s about equity. Families without consistent healthcare access, or those who distrust medical advice due to past bias, are left behind.
And misinformation still circulates. Some believe that avoiding allergens during pregnancy or breastfeeding helps. But Cochrane reviews found no proof. Others think probiotics or vitamin D prevent allergies. Again, no solid evidence. Early peanut introduction is the only strategy with strong, repeated, real-world proof.
The Results Are In
Since the 2017 guidelines rolled out, peanut allergy rates have started to drop. In the U.S., the prevalence fell from 2.2% in 2015 to 1.6% in 2023. That’s 300,000 fewer children with peanut allergy. The biggest drops? In high-risk groups. Babies with mild eczema saw an 85% reduction. Those with moderate eczema? 87%. Even babies with severe eczema had a 67% drop.
And the protection lasts. The LEAP follow-up study showed kids who ate peanut early stayed protected-even after they stopped eating it for a full year. That’s not just temporary tolerance. That’s immune training. Real, lasting change.
What’s Next?
Researchers are now asking bigger questions. Can we prevent multiple allergies at once? The EAT study extension found that introducing peanut, egg, milk, and other allergens together before six months lowered the risk of multiple food allergies-not just peanut. The PRESTO trial, funded by the U.S. government with $35 million, is testing the best timing and dose for high-risk infants. Results are due in 2026.
Meanwhile, the market is catching up. Peanut pouches, powders, and baby-friendly snacks designed for early introduction have grown 27% a year since 2018. But products alone won’t fix this. We need better education for parents and doctors. We need clearer messaging. We need to make sure every family, no matter their background, knows how to protect their child.
The science is settled. Waiting doesn’t help. Early, safe introduction does. If your baby is healthy, start peanut around 6 months. If they have eczema or an egg allergy, talk to your doctor before 6 months. Don’t wait. Don’t guess. Do it right-and give your child the best chance to grow up without fear of a single peanut.
Can I give my baby peanut butter straight from the jar?
No. Whole or chunky peanut butter is a choking hazard for babies under age four. Always thin smooth peanut butter with water, breast milk, or formula to make a runny paste. Mix it into cereal or puree. Never give whole peanuts or large globs of peanut butter.
Is it safe to introduce peanut at home?
For babies with mild or moderate eczema or no eczema at all, yes-introducing peanut at home is safe. Start with a tiny amount and watch for reactions. For babies with severe eczema or egg allergy, talk to a doctor first. They may recommend a supervised first dose in their office to ensure safety.
How much peanut protein should I give my baby?
The recommended dose is 2 grams of peanut protein, given three times a week. That’s about 2 teaspoons of smooth peanut butter. Stick to this schedule consistently-even if your baby doesn’t seem to like it. Regular exposure is what builds tolerance.
What if my baby has a reaction?
If you see hives, swelling, vomiting, coughing, or trouble breathing, stop immediately and call emergency services. For mild reactions like a few hives, contact your pediatrician. Never give peanut again without medical advice. Most reactions happen during the first few exposures, which is why starting small and watching closely matters.
Do I need to keep giving peanut after I introduce it?
Yes. Consistency is key. Give peanut-containing foods at least three times a week, even after your baby has tolerated it. Stopping can cause the allergy to return. Think of it like brushing teeth-regular maintenance keeps the protection strong.
Is peanut allergy prevention only for babies in the U.S.?
No. Guidelines from Australia, the UK, Canada, and Europe all now support early peanut introduction based on the same global evidence. The LEAP and EAT studies involved babies from multiple countries, and results were consistent. This isn’t a U.S.-only approach-it’s a worldwide standard.
Can I use peanut flour or powder instead of peanut butter?
Yes. Peanut flour or powder can be mixed into food to reach the 2g protein dose. Make sure the product is designed for infants and doesn’t contain added sugars or preservatives. Check the label to confirm how much peanut protein is in each serving. Always start with a small amount and watch for reactions.
Does breastfeeding prevent peanut allergy?
No. While breastfeeding has many benefits, studies show it doesn’t prevent peanut allergy. Avoiding peanut in your diet while breastfeeding also doesn’t help. The only proven way to reduce risk is to introduce peanut to your baby directly, at the right age and in the right form.