If you’ve heard you’re supposed to introduce peanuts and other allergens early but feel terrified at the thought of actually doing it, you’re not alone. The idea of giving your six-month-old peanut butter probably feels like the opposite of keeping them safe, even though you’ve been told it prevents allergies.
After introducing allergens to four babies and working with hundreds of families as a lactation counselor and public health scientist, I understand why this feels so scary. The guidance has completely changed from what our parents were told, and now you’re supposed to do something that sounds dangerous based on everything you grew up believing. Add in the fear of missing a reaction or causing your baby to choke, and it’s enough to make you want to skip allergen introduction altogether.
But here’s the reassuring truth: introducing allergens early is one of the safest, most evidence-based things you can do for your baby. And it doesn’t have to be complicated or stressful.
Below you’ll find 20 allergenic foods, from peanuts and eggs to tree nuts like almonds and cashews, fish, and shellfish, with specific preparation methods that eliminate choking risk, clear signs of what reactions actually look like, and practical serving ideas that work even if your baby is just learning to eat.
You’re already doing great by researching this. Let’s make allergen introduction feel manageable, rather than terrifying.
Table of Contents
1. Peanuts (Start at 6 Months)
You’ve heard the old advice to wait until age three, but research flipped that completely. Early introduction actually prevents peanut allergies, especially in high-risk babies. The landmark LEAP study showed that introducing peanuts between 4-6 months reduced allergies by 86%. Mix smooth peanut butter with warm water, breast milk, or formula until it’s thin and runny (about 2 teaspoons of peanut butter thinned with liquid). Never give whole peanuts or thick globs that could block airways. Your baby only needs about 2 teaspoons of thinned peanut butter three times per week to build tolerance. If your baby has severe eczema or existing food allergies, talk with your pediatrician first. They may want to do an introduction in the office, but they’ll still recommend doing it, not avoiding it.
2. Eggs (Start at 6 Months)
Scrambled eggs are one of the easiest first foods because they’re soft, easy to prepare, and babies usually love them. Cook eggs fully (no runny yolks for babies under one) and serve them plain or mixed with a tiny bit of breast milk to make them softer. You can also bake eggs into muffins or pancakes. The whole egg matters, both white and yolk, because the proteins that trigger allergies are in the whites. Don’t stress if your baby just gums it and spits most of it out. Even tiny amounts on their tongue and in their mouth count for building tolerance. True egg allergies show up as hives or swelling within minutes to two hours after eating. A red rash around the mouth from the food touching skin isn’t an allergy; it’s just contact irritation that washes off.
3. Cow’s Milk Dairy (Start at 6 Months)
Your baby can’t drink cow’s milk as a beverage until after their first birthday, but they can absolutely have dairy foods starting at six months. Full-fat plain yogurt is perfect because it’s soft, easy to swallow, and the live cultures are great for gut health. You can also offer small amounts of shredded cheese, cottage cheese, or ricotta. Melting a bit of cheese over steamed vegetables can make them more appealing to reluctant eaters. Skip low-fat or flavored yogurts. Babies need the fat for brain development, and added sugars aren’t helpful. If your baby has a true milk protein allergy (different from lactose intolerance), you’ll see vomiting, diarrhea, or blood in stool. Most babies who seem fussy after dairy are just adjusting to new foods, not allergic.
4. Wheat (Start at 6 Months)
Those first bites of toast absolutely count as allergen introduction. Wheat is one of the easier allergens to introduce because it’s in so many foods babies naturally try. Small pieces of whole wheat toast, pasta, or even baby cereal all work. Make toast strips by cutting bread into finger-length pieces that your baby can hold. You can spread a thin layer of nut butter on toast to knock out two allergens at once. Wheat allergies are pretty rare, affecting less than 1% of children, and most kids outgrow them by school age. The difference between wheat allergy and celiac disease matters: wheat allergy causes immediate reactions like hives or breathing trouble, while celiac is an autoimmune response to gluten that develops over time. Your pediatrician can test for celiac if you have concerns based on family history.
5. Tree Nuts: Almond (Start at 6 Months)
Almond butter works exactly like peanut butter for the introduction. Thin it with liquid until it’s runny and won’t stick in your baby’s throat. You can also buy almond flour and bake it into baby-friendly muffins or pancakes. If you’re introducing multiple nut butters, space them out by a few days so you know which one caused a reaction if something happens. It’s completely normal for babies to make horrible faces when trying almond butter. That sour or bitter taste expression doesn’t mean they’re having a reaction. True allergic reactions show up as hives, swelling, vomiting, or breathing changes, not just funny faces and dramatic shudders. The proteins in almonds are different from peanuts (which aren’t actually nuts), so being allergic to one doesn’t automatically mean being allergic to the other.
6. Fish: Salmon (Start at 6 Months)
Fresh or canned salmon both work perfectly for allergen introduction. Canned salmon is actually easier because it’s softer and the bones are safe to eat. They’re cooked until they’re soft, and they’re loaded with calcium. Flake cooked salmon into tiny pieces and check carefully for any bones if you’re using fresh. You can mix it with mashed avocado or sweet potato to make it more appealing. Salmon has the bonus of being high in omega-3 fatty acids that support brain development. Don’t worry if salmon seems like a “fancy” or expensive first food. A small can costs a few dollars and provides multiple servings for introduction purposes. If your baby refuses fish, try mixing it with a food they already love. The goal is getting some protein in their mouth for exposure, not making them eat a full serving.
7. Sesame (Start at 6 Months)
Sesame became the ninth major allergen recognized by the FDA, which tells you how common sesame allergies have become. Tahini (sesame seed butter) is the easiest way to introduce it. Thin tahini with water or mix it into yogurt, hummus, or oatmeal. You can also crumble a tiny amount of sesame seeds into foods, though whole seeds are a choking hazard until your child is older. Those little seeds on hamburger buns count for exposure if your baby actually eats them. Sesame wasn’t on anyone’s radar for early introduction years ago, when many parents were starting solids. Now we know that sesame allergies can be severe and they’re not usually outgrown, which makes early introduction even more helpful. If you have Middle Eastern or Asian foods in your regular cooking, your baby is probably already getting sesame exposure from those cuisines.
8. Soybeans (Start at 6 Months)
Wondering if tofu seems too bland or weird for a first food? It’s actually perfect. Tofu is soft, takes on whatever flavor you cook it with, and babies handle the texture beautifully. Cut firm tofu into small strips your baby can hold, or crumble silken tofu into purees or yogurt. Edamame (whole soybeans) are too firm and round for babies, but you can mash cooked edamame into a paste. Many babies get soy exposure from soy-based formulas or soy lecithin in processed foods, which also counts. True soy allergies are less common than parents think because many babies who react to soy formula have a temporary intolerance that they outgrow, not a lifelong allergy. If you’re vegetarian or plant-based, tofu becomes a protein staple anyway, so introducing it early serves double duty. Don’t stress about organic versus conventional soy for allergen introduction purposes. The allergen proteins are the same either way.
9. Shellfish: Shrimp (Start at 6 Months)
Shrimp at six months sounds wild, but it’s safe when prepared properly. Cook shrimp thoroughly and cut them into tiny pieces. It’s naturally soft and easy to chew. You can also puree cooked shrimp with vegetables or rice if you’re nervous about texture. Shellfish allergies are more common in adults than in babies, and they tend to be severe, which is exactly why early introduction matters. Your baby doesn’t need a full shrimp cocktail. A few small bites mixed into a meal they’re already eating works fine. If you’re introducing both fish and shellfish, space them out by a few days because they’re different allergen categories. Someone can be allergic to shellfish but fine with fish, or vice versa. Watch for reaction signs, but know that most babies tolerate shrimp without any issues.
10. Tree Nuts: Cashew (Start at 6 Months)
Cashew butter is creamier and milder than almond butter, so some babies prefer it. The same thinning rules apply: mix it with liquid until it’s runny enough to be safe. Cashews are technically seeds, not nuts, but they’re grouped with tree nuts for allergy purposes. One challenge with cashew introduction is that cashew butter is more expensive and harder to find than peanut or almond butter. You might need to order it online or check health food stores. A small jar lasts a long time for introduction purposes since you only need small amounts. If your baby has already tolerated another tree nut, cashew introduction is usually less stressful. You’re not starting from scratch with nut allergen exposure. That said, each tree nut contains different proteins, so tolerating one doesn’t guarantee tolerating all of them.
11. Wheat Pasta (Start at 6 Months)
Your baby is grabbing at your spaghetti. Good news, that’s allergen introduction happening naturally. Small pasta shapes work beautifully for baby-led weaning while introducing wheat allergens. Cook pasta until it’s very soft, almost mushy by adult standards. Shapes like orzo, small shells, or cut-up spaghetti are easiest for little hands to grasp. You can toss pasta with a tiny bit of butter, olive oil, or sauce. Pasta is forgiving because even if your baby mostly plays with it and drops it on the floor, they’re still getting allergen exposure from touching and tasting. The repetition of offering wheat-containing foods several times per week builds tolerance better than one big serving. If you’re already introducing eggs, making simple egg noodles at home combines two allergens in one food. Don’t stress about whole wheat versus regular pasta for allergen introduction. Both contain the wheat proteins that matter for building tolerance.
12. Tree Nuts: Walnut (Start at 6 Months)
Walnuts have a stronger, slightly bitter taste that some babies reject at first. Walnut butter is harder to find than other nut butters, so you might need to make your own by blending walnuts with a bit of oil in a food processor. You can also grind walnuts into a fine powder and mix them into oatmeal, yogurt, or baked goods. Finely ground walnuts in banana muffins work beautifully and make allergen introduction feel less medical and more like normal eating. Walnuts are high in omega-3 fatty acids, like fish, which is great for brain development. The brown skin on walnuts is safe and nutritious, so don’t worry about removing it before grinding. Keep trying even if your baby refuses it the first few times. Repeated small exposures over weeks still provide the allergy prevention benefit you’re looking for.
13. Full-Fat Yogurt (Start at 6 Months)
That sour face your baby makes at plain yogurt? Completely normal and not a sign they hate it. Plain, whole milk yogurt is one of the most popular first foods because babies usually love the creamy texture and slightly sweet taste once they adjust. Greek yogurt has more protein but regular yogurt works just as well for allergen introduction. You can mix yogurt with fruit purees, nut butter, or even a tiny pinch of cinnamon for variety. The live cultures in yogurt support healthy gut bacteria, which might play a role in preventing allergies beyond just the milk protein exposure. Your baby doesn’t need those fancy baby yogurt pouches with cartoon characters. Adult plain yogurt is cheaper and has less added sugar. Keep offering it, and they’ll adjust to the taste.
14. Tree Nuts: Hazelnut (Start at 6 Months)
Most parents assume chocolate hazelnut spread is a fun way to introduce hazelnuts, but check the ingredients first. Most commercial versions contain far more sugar and palm oil than actual hazelnuts. Pure hazelnut butter is better, though harder to find. You can also buy hazelnut flour (finely ground hazelnuts) and bake it into baby-friendly foods. If you can only find chocolate hazelnut spread, a tiny amount thinned with breast milk or formula still provides allergen exposure without too much sugar. Hazelnuts have a sweet, mild flavor that many babies tolerate well. Like other tree nuts, hazelnuts contain different proteins from peanuts, so testing each variety separately matters. Don’t feel pressured to introduce every single tree nut. The most common tree nut allergies are to walnuts, cashews, and almonds, so prioritizing those makes sense if you’re feeling overwhelmed.
15. Tree Nuts: Pecan (Start at 6 Months)
Pecans have a buttery, slightly sweet flavor that’s less bitter than walnuts. Pecan butter exists, but you’ll probably need to make your own by processing pecans with a touch of oil until smooth. Ground pecan meal mixed into pancakes or muffins works beautifully and adds a subtle nutty sweetness that babies often enjoy. You can also finely grind pecans and stir them into oatmeal or yogurt. The key with all ground nuts is making sure they’re fine enough that they won’t clump in your baby’s throat. Pecans are lower in protein than almonds or peanuts, but they still contain the tree nut allergens you’re trying to avoid. If your family bakes pecan pie for holidays, those pecans are usually chopped small enough for older babies to try tiny amounts, though skip the sugary filling.
16. Cheese (Start at 6 Months)
Shredded mild cheese melts beautifully over vegetables, scrambled eggs, or pasta, making foods more appealing while introducing dairy allergens. Start with milder varieties like mozzarella, mild cheddar, or Monterey Jack because sharp cheeses can be overwhelming for new eaters. String cheese pulled into small pieces works well for babies practicing their pincer grasp. Full-fat cheese provides calcium, protein, and vitamin D, along with the fats babies need for development. Don’t worry about giving too much cheese. At this age, breast milk or formula is still providing most nutrition, so cheese is mainly for allergen exposure and taste exploration. Some babies get constipated from too much dairy, but a few small servings of cheese each week shouldn’t cause problems. The white chalky bits in your baby’s diaper after eating cheese are just undigested milk proteins, not a sign of allergy or intolerance.
17. Fish: Cod (Start at 6 Months)
Cod has a milder flavor than salmon, which makes it easier for some babies to accept. It flakes easily when cooked and has a soft texture that doesn’t require much chewing. Steam or bake cod until it’s fully cooked and falls apart easily, then check obsessively for bones because cod can have small pin bones. Mix flaked cod into mashed potatoes, rice, or pureed vegetables if your baby seems unsure about plain fish. Fish sticks use cod, but most commercial versions are breaded and fried, so making your own by baking small pieces of cod with a light coating works better for young babies. You’re looking for allergen exposure, not a full fish dinner, so even a few flakes mixed into familiar foods count. Different fish species contain similar but not identical proteins, so introducing variety beyond just one type of fish makes sense.
18. Shellfish: Crab (Start at 6 Months)
Real crab meat (not imitation, which is just processed fish) provides shellfish allergen exposure with a sweet, mild taste many babies enjoy. Fresh crab is expensive, but canned lump crab meat works perfectly and costs less. Check extremely carefully for shell pieces because even tiny fragments are sharp. Flake crab into very small pieces and mix it with avocado, cream cheese, or mashed sweet potato. Crab cakes seem fancy but they’re just crab mixed with binder and seasonings, then cooked until soft. You can make baby-friendly versions without heavy breading or spices. Crab tends to be the shellfish babies like best, probably because it’s naturally sweet and less “fishy” than shrimp. Crab and shrimp are both crustacean shellfish, different from mollusks like clams or oysters, though all count as shellfish allergens.
19. Cottage Cheese (Start at 6 Months)
The lumpy texture of cottage cheese seems challenging for babies, but most handle it beautifully. Full-fat cottage cheese provides dairy allergen exposure with lots of protein and calcium. You can serve it plain, mixed with mashed fruit, or stirred into scrambled eggs. Some babies pick up the curds individually, which is excellent fine motor practice, even if most end up on the floor. If the texture really bothers your baby, blend cottage cheese smoothly and use it like yogurt or mix it into purees. Small curd cottage cheese is easier for babies to manage than large curd. The liquid whey surrounding the curds is totally safe and nutritious, not something to drain off. Cottage cheese often gets forgotten in favor of yogurt, but it’s cheaper per serving and just as effective for introducing dairy allergens while providing nutrition.
20. Tree Nuts: Pistachio (Start at 6 Months)
Pistachio butter is the hardest nut butter to find in regular stores, so ordering online or making your own might be necessary. Ground pistachios work well mixed into baked goods, oatmeal, or yogurt. The green color sometimes makes foods more interesting to babies who are visual eaters. Pistachios have a slightly sweet, mild flavor compared to stronger nuts like walnuts. You’ll need to remove shells completely if you’re grinding whole pistachios, and make sure you’re buying unsalted ones since babies don’t need added sodium. If your budget is tight, pistachios are probably the tree nut you can skip since they’re expensive and harder to prepare than almonds, cashews, or walnuts. That said, if you regularly cook Middle Eastern or Mediterranean foods, pistachios might already be in your kitchen, making the introduction more convenient than buying yet another specialty nut butter.
You’re Protecting Your Baby’s Future, One Food at a Time
That terror you felt about giving your six-month-old peanut butter? Now you know exactly how to do it safely, and you understand why early introduction actually protects them instead of putting them at risk. That shift from fear to confidence is exactly what you needed.
For your very first allergen introduction, try thinned peanut butter mixed into warm oatmeal tomorrow morning. Just 2 teaspoons of smooth peanut butter stirred with breast milk or formula until runny. Three days later, offer soft scrambled eggs. Keep it low-pressure and introduce just one new allergen every three days so you can watch for reactions.
Yes, your baby might spit out that first taste of peanut butter oatmeal or smash egg all over their face. That’s not a failed allergen introduction. That’s your baby’s immune system getting exactly what it needs to stay healthy for life.
You’re doing something genuinely protective here. Happy feeding!