Heavens yes.
I CANNOT eat most of the things I am allergic to. Several of the things I'm allergic to can kill me if I eat them. I've been taken to the ER in respiratory distress thinking food allergies weren't a "big deal" (although I should have known better) and they hit me so hard I nearly died. Don't take a chance, a "mild" allergy can turn into a deadly one in ONE taste. Your body develops a stronger reaction every time you are exposed to the food, so your next bite could be your last, really.
I'm allergic to shellfish and iodine. This closes my windpipe, my blood pressure drops to zero over zero and I break out in hives and I can't breathe. Even smelling shellfish makes my knees weak. This is the stuff that sent me to the ER and nearly killed me.
I'm allergic to peanuts and it's almost as bad as the shellfish. A few years ago I bit into a granola bar that had recently started using peanut flour as a "protein" booster, and I got very sick. An inhaler, some benadryl, my EpiPen and consideration about going to the ER was waiting. Even the smell of peanuts or peanut butter makes me ill.
I can't touch cow based dairy products, with the exception of butter (no proteins in butter, so I'm safe.) But, I'm also lactose intolerant (which is NOT an allergy, but an inability to break down the sugars in dairy products) so I stay away from the stuff. I can eat a little goat cheese, but I eat it with a large quantity of LactAid. (The proteins are different, so there isn't a true allergy there for me.)
I'm also allergic to corn and barley. Who the hell is allergic to barley? Probably because they used to make baby cereal with it, and I was put on solid food at only a few weeks of age. I was also put on cow's milk at only a few months of age, so it's obvious where that allergy came from. I can tolerate organic corn on the cob, if I stick to one half cob. I don't get hives or respiratory issues with this, though. If your allergies involve difficulty breathing, sighing, itchy mouth or increased yawning, or hives you should stay away from that food entirely.
I get migraines from nitrates and bananas, I'll get a migraine within 30 minutes of eating even a bite of banana. And chocolate during my period. These are not true allergies, but a reaction to the tyrosine and aldehyde in these foods.