11 of the Most Common Food Allergies You Need to Know

While some of us were lucky enough to eat all the chocolate-covered almonds and cheesy snacks we wanted as children, many others had limited diets because of food allergies. In fact, 1 out of 13 children in the U.S. has an allergic reaction to certain foods. And it’s no joke — it can potentially cause serious damage.

When understanding how these allergies develop, it’s important to know the role of the immune system. This system targets and attacks bacteria and viruses that can potentially make you sick. In an ideal situation, all would work perfectly and only the germs would be destroyed. But your immune system can sometimes target certain food proteins, believing they are threatening to you, says Food Allergy Research & Education. This is why those with food allergies feel ill after consuming the same thing again and again.

Curious if your post-dinner stomachache could be a little more serious than you think? These foods are the most likely culprits.

1. Peanuts

bowl of peanuts

This is a very common allergy. | iStock.com

This allergy is extremely common, and while most of us assume being allergic to peanuts means you’re also allergic to other nuts, that’s not necessarily the case. Peanuts are legumes — a totally different category than almonds, cashews, and Brazil nuts.

What’s concerning about a peanut allergy is it’s commonly associated with anaphylaxis, says the American College of Allergy, Asthma, and Immunology. This condition requires medical attention immediately, as it can cause swelling in the throat, tightness in the chest, or a weak pulse. While peanut allergies seem to be on the rise, a study shows the best way to prevent peanut allergies in children may be to introduce the food early on in infancy. More tests need to be done, but it’s looking positive so far.

2. Tree nuts

A close up shot of macadamia nuts laid out on a wooden table.

Many people have a reaction to tree nuts. | iStock.com/pinkomelet

Now for those who can eat all the peanut butter they want but have to avoid the almond butter. Tree nuts are another very common allergy, affecting kids and adults alike. While many people who have to avoid almonds and cashews can still eat peanuts, for some unlucky few, nuts of all kinds are totally out. Healthline reminds about 25% to 40% of those allergic to peanuts are also reactive to tree nuts.

We can all spot a tree nut when we see one — problems arise when certain foods that look innocent actually contain a small amount. Cold cuts, cheeses, frozen yogurts, and condiments can all be potential offenders. And take a look at your shampoo, too — you may be surprised to see it was packaged in a facility where tree nuts were handled. But being allergic to tree nuts doesn’t mean you’ll always have an adverse reaction,so it’s worth asking an immunologist if you’re curious.

3. Dairy

dairy products

Dairy products are a common food allergen. | iStock.com

A dairy allergy and lactose intolerance sound like they’d be the same thing, but don’t get confused. WebMD explains lactose intolerance is when you can’t digest the sugar found in dairy products, known as lactose. Really, the only discomfort you’ll have from this issue is in your stomach — you’ll often have pain, gas, and bloating.

On the other hand, an allergy is an immune system problem. In this case, you may experience wheezing or skin issues that wouldn’t be caused by a lactose intolerance. When you have a dairy allergy, you have to be extra careful about what you’re putting into — or even on — your body. Many body lotions and ointments contain milk proteins, which can give you issues. Also, you may think you’re safe with sheep or goat’s milk, but the proteins in those are similar to cow’s milk, so it’s usually a no-go.

4. Egg

raw eggs

Eggs can cause some problems. | iStock.com/svehlik

You might not think you know too many people with this problem, but eggs are actually the second most common food allergy in children and infants. And, because there are multiple parts to an egg, some people are allergic to the whites, whereas others are allergic to the yolks. Livestrong.com says if you have this allergy, you’re most likely to have a reaction to raw egg whites as opposed to cooked whites or any other part of the food.

It’s not all bad news: If you have an infant with an egg allergy, there’s a good chance they’ll grow out of it by the time they’re seven, Dr. Anthony Ham-Pong, a private practitioner, tells the publication. Eggs are a tough food to get away from, especially if your diet is composed of a lot of processed foods, so read labels.

5. Soy

tofu

You’ll want to skip the tofu with this allergy. | iStock.com

Soy sauce is too salty and tofu’s a weird texture, so hey, you might not think a soy allergy would be so bad. Unfortunately, soy is in a ton of foods — and you might not even realize it. You know monosodium glutamate, better known as MSG, is what makes your takeout taste so awesome, right? That’s a form of soy. .

Soy is a member of the same family as peanuts. The good news is if you are allergic, it doesn’t mean you’re allergic to all legumes, says Verywell. If you do have an allergy, you’ll need to be vigilant in knowing what products contain soy. Many infant formulas contain the ingredient, as do some lip balms, cosmetics, and coatings on vitamins. Soybeans are a huge part of processed food, so having this allergy can be a real challenge.

6. Finned fish

tuna steak

Tuna won’t be on your dinner menu if you have this allergy. | iStock.com

Though an allergy to shellfish is more common, having no reaction to clams doesn’t mean you’re fine to eat that salmon fillet. The Food Allergy and Anaphylaxis Connection Team explains it’s more common for adults to be allergic to finned fish than it is for children. While many kids are able to overcome their intolerances as they age, this is unlikely to happen for adults who take issue with fish. And if you do have this allergy, it’s unlikely only one fish will trigger unwanted symptoms — you’re probably allergic to multiple types.

If you are allergic, it’s possible eating that bite of tuna will only lead to mild symptoms. Unfortunately, many reactions to fish are severe and require urgent medical care. You probably think it’s pretty easy to steer clear of this seafood, but always check your labels. Anchovies are usually in homemade Caesar dressings, and fish stock may be in soups and stews.

7. Shellfish

Clams Steamed in Sake

This is a very common allergy. | iStock.com/y_seki

This is another one you’ve definitely heard of, and maybe even an excuse you’ve used to get out of eating raw oysters at your friend’s family party. The strange this is some people are only allergic to one or two kinds, while others can’t get anywhere near this type of seafood, Mayo Clinic explains. Why? There are actually two types of shellfish — crustaceans and mollusks. Crabs and lobster are crustaceans, and squids and octopi are mollusks. It’s very possible to be allergic to one kind and not the other.

Shellfish allergies are also more common in adults, and women are more likely to develop the issue. In children, however, it’s the opposite. Boys are diagnosed more often than girls. It shouldn’t be too hard to avoid the allergy if you have it (hint: Shellfish usually have visible shells), but not all types of this fish are so obvious.

8. Wheat

wheat next to some grains

A wheat allergy is not the same thing as celiac disease. | iStock.com

Don’t get confused — a wheat allergy, celiac disease, and gluten intolerance are not all the same thing. When you have a wheat allergy, your body overreacts to the proteins in wheat. With celiac, your body has an abnormal response to gluten, which hurts the small intestine, FARE explains. If you have celiac and you keep eating foods containing gluten, you can become malnourished and have serious intestinal damage. With a wheat allergy, you’ll just have a normal allergic reaction that can range from mild to severe.

If you’re allergic to wheat and you cry at the thought of giving up pasta, have no fear — there’s a good chance there are other wheat-free grains you can safely try. Barley, rye, and oats are generally safe, but there is the chance you won’t tolerate any grains at all. Ask your doctor if you’re curious.

9. Corn

corn on the cob

Corn products are hard to avoid. | iStock.com

This isn’t the most common allergy on the list, but you should still be aware it exists. If you do have a reaction to corn, here’s the good news: It’s usually not anyone’s favorite vegetable anyway. The bad news? Corn products are in nearly everything.

High-fructose corn syrup is used in place of sugar in many packaged products. So you’ll want to avoid this ingredient, which is very hard to do. Even if you do your best to avoid products that contain corn and this sugar substitute, you’ll want to know other ingredients that typically contain traces of this food. The ACAAI says baking powder, MSG, vanilla extract, and xanthan gum can all trigger a reaction if you’re allergic. You’re also sure to find traces of corn in your shampoo, toothpaste, and clothing.

10. Seeds

poppy seeds in a wooden spoon on a wood table

Seeds can cause some people problems. | iStock.com

You might not think twice about the seeds on your sesame bagel, but these tiny seeds can cause big issues for some. Allergy UK explains you can be allergic to multiple types of seeds, but one related to sesame is the most common. The first reported allergy to this tiny food was in the 1950s, and since then, it seems as if more and more cases have cropped up. And sesame isn’t the only type of seed that can trigger a reaction — there’s also a chance poppy seeds, sunflower seeds, or mustard seeds can cause issues.

Many breads and bakery items contain seeds, but also look at the ingredients of your favorite hummus or tahini varieties. Your pharmaceuticals or cosmetics may have seed products in them as well, so remember to check. Also, keep in mind the fresh bagel with the sesame seeds sprinkled on top is less likely to give you a problem than, say, sesame oil. This is because the protein that causes the allergic reaction is only exposed if the seed is broken.

11. Oral allergy syndrome

woman coughing

People with OAS usually get an itchy throat after eating certain produce. | iStock.com

No one likes the feeling of an itchy mouth and throat. Unfortunately, some fruits and veggies induce this uncomfortable sensation for those with oral allergy syndrome. The AAAAI explains oral allergy syndrome is a contact allergic reaction that occurs when the mouth and throat touches certain fresh produce. Depending on what seasonal allergies you have, you’ll react differently to certain fruits and veggies. This is because some of the proteins found in these foods are similar to those found in pollen, grasses, or ragweed.

Have a reaction to birch tree pollen? Pitted fruit and carrots may give you this reaction. Feel itchy around grass? You might want to stay away from peaches, celery, tomatoes, melons, and oranges. If ragweed is what takes you down, stay away from bananas and cucumbers.

The good news about this allergy is it’s usually not very serious — you’ll just experience some discomfort. Try peeling these foods before eating them, too. Usually, the protein that causes the reaction is found in the skin.

Allergy vs. intolerance

children sitting together at a birthday party

There’s a big difference between an allergy and an intolerance. | iStock.com

Now, there’s a big difference between the person who can’t eat peanut butter because of possible shock and the person who won’t eat gluten because they feel slightly tired and bloated after consumption. The big difference between the two is how your immune system responds. According to Mayo Clinic, when you eat a food you’re allergic to, it’ll trigger a response in your body that affects multiple organs. These symptoms can be quite severe or even life-threatening, though they aren’t always — sometimes you’ll just notice a rash or itchiness in your throat. Either way, the food allergen causes your immune system to go haywire, whereas an intolerance isn’t typically as harmful.

If you’re sensitive to certain foods but eating them doesn’t trigger an immune system response, then you’ll likely feel some discomfort, but you won’t be in any real danger. You might even be able to eat small pieces of the offending food here and there without any issue.

Symptoms of a reaction

Woman scratching her arm

There are many different symptoms of an allergy. | iStock.com/Tharakorn

Ideally, having a food allergy would be easy to spot — maybe you’d get hives after eating something with soy, or peanuts would always give you stomach pain. Unfortunately, it’s not always that easy to spot. Some people experience mild symptoms like skin rashes, sneezing, or an itchy mouth, while others have more severe signs like obstructive throat swelling and trouble swallowing.

When dealing with children who have food allergies, it can be even harder to know whether or not they are having a reaction. Kids won’t describe their symptoms they way you would, so FARE suggests taking note of some common things a child might say when food is causing them discomfort. If they’re very young, they might scratch at their tongues or slur their words, or their voice might change. Otherwise, they may say they feel as if their tongue has hair on it, theirs a frog in their throat, or something’s poking their tongue and mouth. Pay attention to the funny way your child may try to communicate the issue — it might sound easy to brush off, but something more serious could be happening.

Testing for an allergy

a doctor holding a tablet

Ask your doctor about your options. | iStock.com

Think you may have a food allergy? It’s important to approach a medical professional before you start trying to self-diagnose. An allergist will first ask you about your symptoms after eating the food you think you may be allergic to. From here, they may choose to do a skin prick test. It’s important to note that while this type of testing will seldom product false negatives, it does sometimes produce false positives, says FARE. This means you could have a test that says you’re allergic to something even though you’re really not. Alternatively, you can choose to get a blood test, but this also typically has the same accuracy.

Don’t get us wrong — skin and blood tests do have their place. If you notice you consistently have a reaction to soy products and your test tells you you’re allergic to soy, then there’s a good chance you do have this allergy. If results are inconclusive, then your doctor may request you try something a little more long-term than just one test. This leads us to our next point…

Try an elimination diet

Woman on gluten-free diet

Eliminating certain foods can help you find out if you have an allergy. | iStock.com/lolostock

Your allergist may recommend you try an elimination diet if the results of testing are inconclusive. The idea of this diet is simple — you eliminate the food you believe you’re allergic to for 23 days to see if your symptoms disappear. Why 23 days, you ask? Mindbodygreen says it takes about 21 to 23 days for your antibodies, the proteins your immune system creates when it has a reaction to food, to turn over. Getting rid of the food for two weeks won’t cut it.

After you’ve gone without wheat, soy, or whatever your allergen may be for 23 days, on day 24, you can slowly start to incorporate it back into your meals. Take note of how you’re feeling — did your symptoms disappear during the elimination phase and then reappear once the food was added back? If you’re eliminating more than one food allergen, only add one back in at a time until you can fully gauge whether or not it’s affecting you.