Austin has always claimed that certain foods make his mouth itch. This isn't any kind of harbinger of anaphylaxis that would accompany him eating a peanut. Instead, it's an annoying mouth itch that is strong enough to dissuade him from wanting to eat a food, but has little other consequences.
Anyway, not that many years ago when he was in grad school he figured out that his weird mouth-itching thing actually had a name and was a documented occurrence called oral allergy syndrome.
This is from Wikipedia:
"Oral allergy syndrome or OAS is a type of food allergy typified by a cluster of allergic reactions in the mouth in response to eating certain (usually fresh) fruits, nuts, and vegetables that typically develops in adult hay fever sufferers.[1] Another term used for this syndrome is '"Pollen-Food Allergy."' In adults up to 60% of all food allergic reactions are due to cross-reactions between foods and inhalative allergens.[2]
In OAS, the immune system produces antibodies that are capable of binding to both pollen proteins and structurally similar food proteins. Consequently, the same immune system response can trigger allergy symptoms in two different situations: hay fever (in the presence of pollen) and food allergy (in the presence of certain foods). Histamine releases from mast cells located in the oropharynx, gut and skin when IgE binds to the molecule causing local inflammation - itching, swelling, pain, and so on."
So, basically, something about a lot of uncooked fruits and vegetables is similar to some seasonal allergen Austin's allergic to, and so he gets seasonal allergies of the mouth when he eats them. Bizarre.
Tomatoes, cut cucumbers, lettuce... all those are fine, but I start getting into lots of trouble if I add green peppers or carrots to our salads. Any peeled fruit doesn't bother Austin, but the last thing he'd want to do is bite into a crisp apple in the fall. It makes apple picking with him funny, because the whole point of the expedition is to eat apples, right?
