Serious physical problems will occur if I eat this food (life-threatening, necessitating medical attention, or causing significant discomfort).
None that I'm aware of.
Mild physical problems will occur if I eat this food (a bit itchy or queasy, but tolerable).
More than a small amount of meat, esp beef. I was vegetarian for three years, and have never fully recovered the ability to digest red meat. I can eat maybe eight ounces of red meat in a day, if it's not all beef and not all at one sitting.
Physical problems will occur if I am in the same room as this food.
The smell of mushrooms cooking makes me queasy, and I'll leave a room to avoid it if it's strong enough. (This is mainly just about white button mushrooms and portobellos -- Asian varieties are mostly OK, as are some of the frilly European ones like chantarelles.)
I also find some of the odors in Japanese food unpleasant, though not quite that bad. I like hibachi grill/stirfry stuff, and I like tempura and teriyaki, and even find miso OK; but sushi, and those pickly things, turn my stomach. I've never been quite sure what it is, but there's an odor hangs in the air in sushi places that smells (to me) like decay. Not at all appetizing.
For religious/ethical reasons, I will not eat this food.
The more I learn about the current state of the meat industry, the more averse to it I become. I heard a talk on the radio yesterday by Robert Kennedy, Jr, in which he described just how bad the hog industry is... I still am not quite at the point of turning vegetarian again, but I'm thinking I'm going to at least make a point to look for organic/farm-raised stuff. I already buy free-range eggs.
I just plain really don't like this food.
Mushrooms, as mentioned above -- and no, they can't be picked out of things, as their flavor infuses everything else they're cooked with. Blech. I have similar, though not quite so vehement, feelings about green bell peppers.
Cheese should not be visibly moldy. Nor should it have trouble standing as a solid block.
This food is a mild dislike, but I'll eat it sometimes if it's in a dish.
Red bell peppers (though they can be quite good if they're thoroughly roasted and embedded in the right other flavors).
Eggplant (though similar comments apply as to red bell peppers; I sometimes like eggplant on pizza).
Most shellfish. (And yet I like Maryland crab soup, and New England clam chowder. I also often like lobster and crab meat in pasta, salad, etc.)
I used to dislike Mexican stuff, but I've developed more of a taste for it over the last few years. (I think Cuban was kind of a "gateway" cuisine to Mexican.) I'm still not overly fond of Mexican bean-intensive stuff (and it's not just about the beans; I very much like Italian bean dishes like pasta fagiole, bean or lentil based soups, etc).
I try to avoid heavily processed foods (e.g. cakes made from mixes, anything from any fast food chain), especially those that contain corn syrup and/or hydrogenated oils.
As long as we're on the topic, what foods do you like best?
I have a rather dairy-intensive diet; that's where I get the majority of my protein. I love cheese (I like French cheeses least; I'm mainly in favor of Italian, Spanish, Greek, Dutch, Swiss, and Scandinavian, though I'm also fond of some British stuff -- mostly cheddar and its relatives, like Dubliner and Scotch Truckle -- and of course all my favorite Indian dishes include paneer), and I drink a lot of milk. I also love ice cream, esp international varieties like gelato, kulfi, etc. Puddings and custards are good too, esp creme brulee, flan, and other caramel-ish varieties.
I think my fav cuisines are probably Afghan, Indian, Italian, and Thai (in roughly that order), but I have pretty broad tastes. I also like Chinese, Cuban, Indonesian/Malaysian, Filipino, Ethiopian/Eritrean, Cambodian and Laotian (which are more different from Thai, and from each other, than you'd expect), Provencal, Bretagnese, Persian, Greek, Eastern European / Jewish (latkes, blintzes, knishes, rugelah, etc), some Japanese, and some Central and South American stuff. (I'm a big fan of Central and South American styles of preparing chocolate and coffee, and I particularly love mole, which is a bitter chocolate and hot chili sauce.)
I like things that are new and intriguing. c.f. Asian-Accented Squash Soup. I'm a big fan of Iron Chef.