Itchy and watery eyes, nausea, a sneeze attack—these mild to severe symptoms plague the nearly 15 million Americans who suffer from food allergies, according to the Centers for Disease Control and Prevention. Problem is, most of the time we don't associate these freak-outs with food allergies, so they go unnoticed and untreated.

Even as more adults are being newly diagnosed with food allergies, it’s still unclear whether these allergies have simply gone unnoticed or have just developed over time, says Paul Bryce, Ph.D., associate professor of medicine, division of allergy-immunology, at Northwestern University's Feinberg School of Medicine. 

In any case, they're annoying. Allergic reactions to food range from mild skin irritations, coughing fits, nausea, and diarrhea—to severe reactions like anaphylaxis, or difficulty breathing, swelling or tightness of the throat, chest pain, trouble swallowing, and dizziness. More extreme cases may even require you keep an injectable epinephrine (EpiPen) on hand at all times.

Unfortunately, there's no cure for food allergies, but if you’re noticing recurring symptoms and still don’t know the real culprit, see an allergist. “Food allergies are not something to be taken lightly or diagnosed over the Internet,” says Bryce. “There are tests that can be performed in the clinic and laboratory to determine which foods someone is actually reacting to, and extensive advice on how to respond appropriately when a reaction occurs.”

Whether they force a simple gesundheit or a trip to the emergency room, these five food groups should be in the front of your mind the next time you feel a little funny after noshing on nuts or milking your fridge’s dairy supply.