Any food can cause a reaction, and reactions can range from anaphylaxis to a rash or some degree of swelling. But how do you figure out which foods you’re allergic to?

Well, if you’re having a reaction, chances are you’re dealing with “the Big 8.” These are the most common food allergies, and 90% of food allergy conditions in the U.S. can be narrowed down to them.

Cow’s Milk

Among children, this is the most common food allergy. While it is distinct from lactose intolerance, it can cause rashes, swelling, and in rare cases, anaphylaxis, in addition to stomach cramps.

One of the worst things about a milk allergy is that it’s hard to navigate. Milk is prolific: ice cream, butter, cheese, and many other foods.

Fortunately, the majority of children outgrow the condition.

Eggs

Egg allergies, while slightly less common than milk, are no less tricky to navigate. The proteins in egg whites and yolks can trigger different reactions, or none at all (though egg whites are usually the culprit).

Now, the strategy here, as with most food allergies, can be to cut out eggs entirely; however, sometimes foods with cooked eggs in them don’t produce reactions. Checking with your doctor is imperative before introducing foods with eggs, though, because reactions can still be severe.

And, as with milk allergies, most children will outgrow their egg allergy.

Peanuts

In addition to being one of the most common food allergies, an allergy to peanuts is one of the most fatal. Even trace amounts can cause a severe reaction, so being aware of their presence in all foods is imperative.

About 20% of peanut allergies will resolve over time, but until then, and for those whose allergy remains, total avoidance of peanut allergen is recommended. Palforzia, an oral peanut immunotherapy product, is now available for treatment.

Shellfish

Unlike the others, shellfish allergies usually don’t resolve. If you’ve got it, you can expect to cut out shrimp, prawns, lobster, squid, and other crustaceans from your diet.

Wheat

Wheat covers a wide umbrella of foods, which makes it both hard to identify the allergy (it’s often mistaken for celiac disease and gluten-intolerance), and hard to avoid. Reactions can be severe. Thus, meeting with a doctor to discuss avoidance and treatment strategies is very important.

Soy

This allergy is far less common than some of the others, and symptoms are usually mild. It is present most often in infants, and it is usually outgrown.

Avoidance is the only treatment.

Fish

Fish allergies are fairly common, affecting both children and adults, and they can develop as an adult.

This is distinct from a shellfish allergy, but it can be no less severe. Being properly prepared for a reaction by having a doctor-supplied epi-pen is the best way to deal with a strong reaction but avoiding them altogether is even better.

Tree nuts

Tree nuts can include almonds, walnuts, cashews, pistachios, macadamia nuts, as well as others. Some butters and oils, and other products made from these nuts, can also produce allergic reactions, and should be avoided.

As with peanuts, these allergies can be severe. According to Healthline, nut allergies are responsible for 50% of deaths related to anaphylaxis. Thus, the best treatment is total avoidance. It’s better to not eat trail mix than have a potentially life-threatening reaction.

Food allergies can be seriously inconvenient and hard to determine. Seeking medical advice to figure out which foods to avoid and to what degree is an important part of the process. Doctors will know best what’s wrong, and what to do.

In the meantime, knowing the shortlist of the most common food allergies can help make life easier until you schedule that appointment.