I've had this issue for over 27 years, so I doubt I'll suddenly get any sort of a resolution to the issue, but I figure I may as well ask anyway.
I have an incredibly restricted diet. Being in the same room as many foods causes my throat to close and sends my brain into a panic from the smell. In the case of spicy foods, the smell burns my throat as well. Many foods that I can be in the same room as will still cause my throat to close if I attempt to eat them. As a result, I rely very heavily on dairy for nutrition, and eat a lot of carbs. Fairly tasteless, bland, sweet-ish foods. I drink about a gallon of 1% milk per 2-3 days.
The only time I've seen anyone else react the same way as me was when a man boarded a subway car covered in his own feces. So I assume the reaction I'm having is suppose to occur at a higher threshold than where it's occurring.
I've seen a doctor about this. He said my nose and throat look fine to him.
I have a ton of food allergies including one that I can't even enter a restaurant that serves it as it aerosolizes and gets into the air where I can breathe it in. But to have a food allergy, you must someone ingest or breathe it in. Having your throat close just from being in the room with the food....that is psychological.
It sounds far more like an anxiety reaction to be overwhelmed with the food...the smells the tastes, the colors the types....you feel so overwhelmed, your throat just closes so you can't eat anything.
I would check with an eating disorders clinic and see if they treat your kind of food anxiety. It's not physical. And it is common. Due to my problems with that one food that can kill me I am so allergic, I get panic stricken at certain places in fear they changed the menu and brought in the food. I've made waitresses go and take photos of the ingredient lists so I know whether or not a certain ingredient is in there. I've walked out of others if I find out they use it in cooking. I kicked my own son out of the house for bringing it into the house and cooking with it...like he was trying to kill me...that is how it made me feel. So I understand food anxiety. It is very real.
Since you don't seem to have food allergies(or haven't mentioned any) and your throat is okay, I suspect your stomach can't take anything because of anxiety......anxiety can make you feel really ill and start vomiting and do all sorts of stuff to your digestive system. You need to figure out why and perhaps you'll be able to eat more items.
I hope you'll find a eating disorders clinic and ask for their help. It may change your world.
Given the things you mention, there's more that becomes relevant:
I can sense things a little beyond the norm. My vision, for example, is at least 20/15, if not 20/10. At my previous place of employment, I could smell when pizza arrived to the building, from 4 floors up with a closed glass door in the way. All of my senses are like this. (Some of my friends joke that I have Spidey-Senses, as I seem to know a lot before they do.) So the idea that they may be getting overwhelmed makes sense. I know that when I touch certain fabrics, like velvet, they overwhelm my sense of touch causing my fingers to itch for a while. For my aunt, I know that such a fabric would cause her actual pain. I believe that this heightening of my senses is related to a very mild autism.
There are associated fears and such with this... But these exist as a fear of the issue itself. Like, seeing someone pull out a paper bag, I might think "Oh crap, what am I about to smell? Am I going to be able to breathe?", which I'm sure makes the original issue worse, but I can't look into removing the psychological layers until the core of the problem is removed.
As for what I can look into... I have no health insurance right now. But perhaps when I do, I can look into it.
I thought a bit more about your suggestion, but really don't see how it's possible to be psychological because it's been an issue since before I could speak. I know there are psychological layers on top of it, but the core is certainly physical. Once the core is fixed (if I ever find some way to fix it), I'll spend the time to work on removing the outer psychological layers. Until then, it's a waste to do so, as they constantly grow back.
You are very right in that these extremely heightened senses are "sometimes" associated with autism but I know I have a sense of smell akin to yours. I can smell things no one else can. And I can see colors that others can differentiate. My son just bought a house he swore was blue...it's green. I chose all the colors for the rooms and he liked the light blue I picked for the bedroom...it's green. Both him and wife think it's between green and blue but it is most decidedly green!
People like you are used in the perfume industry....your nose could make you some big bucks if you could learn to use it and not fear it. It's the fear part that I worry about, not the heightened senses. And I guarantee you were born this way so your senses would have made you picky when very little if you feared the intense smells instead of loving them.
Heightened senses can be a blessing or a curse depending on how you see it. I see it as a blessing as I can smell flowers no one else can and I can also smell gas in the air when others can't and saved my family one time from a gas leak no one else smelled. Then again, I can tell each of my cats and my family members apart by the other kind of gas they leave behind.
What you and I have are senses that we had when we were primates and those senses saved us....we could smell a predator before anyone else. Don't know what my heightened sense of color would accomplish but perhaps I knew which berries were the non-poisonous ones.
If you can learn to love your sense of smell and not make you fearful of the foods you eat, you might learn to be a great chef or a great maker of perfumes. You have a gift...learn to love it.
I've always wanted to be able to use it as more of an asset than it's been... So I certainly want to be able to simply not have a problem in the presence of problematic smells. I have tried (and failed) to phase in such smells, but it just doesn't work.
It is known that I have a very mild autism. Because heightened senses are sometimes associated with it, I assume they're related. It could be a coincidence though and I simply have them separately.
My kitchen right now is actually a green that often looks blue in certain lights. Though, most people will see both colors depending on where they look.