Actually yes, it did get narrowed down although it took several years. I saw many doctors, but based on the symptom of nausea it could probably have been thousands of possibilities. It was only 5 years later when the symptoms became more plentiful and more localized I could see a pattern.
The first symptoms back in 2005 were periodic nausea in the morning with dizziness, loss of balance and headaches. I was too old to be pregnant. Then my eyes started to hurt and I went through too many bottles of eye drops which only worked temporarily .
Then I started to get mouth ulcers with my tongue coating turning white when I was especially ill. My teeth got sensitive and hurt. I took ibruprophen for pain until I had to see the doctor for severe stomach aches. They told me to stop taking the ibruprophen and the stomach aches stopped.
Later I started sneezing, got nasal inflammation, skin rashes. I assumed from the nasal inflammation that it could be allergies, but from what? I started to take anti-histamines which in the beginning helped, but my right eye would now start to cloud up on a daily basis, regardless.
Then both my arms started to hurt and I got extreme fatigue to the point I couldn't move. I had to lay down for hours on end and lost work because I didn't have the strength to stand up.
Then I started to get acid reflux that would wake me up in the middle of the night and I had to sleep for weeks sitting up. These latest, more localized symptom made me think my allergies could be food related as I did notice I would start to sneeze when I put certain foods into my mouth.
Through my own testing I found I got allergic reactions to all carbs and sugar. Which means I had to cut out bread, rice, noodles, corn, potatoes, pastries, beer, any processed foods. I went on a diet of raw lettuce, apples, carrots, cauliflower, hamburger (cooked) and sauercraut. It took me over a year to adjust to this weird but healthier diet.
I wondered with ageing if I was losing digestive enzymes. That maybe certain foods weren't being digested and my immune system was treating the undigested food as foreign substances. I tried supplemental digestive enzymes, but they helped, but made my eyes cloud over even more.
During my food testing, I thought a wee biteful of curry would send me to emergency, but after one mouthful I oddly felt better for it.
This lead me to wonder about stomach acid deficiency that you can get as you age and body ph balance. I then tried apple cider vinegar and it helped, but kind of rough to take. Kimchee (which supposedly has great enzymes), pickles, sauerkraut, jalepeno peppers (esp. the juice), curries worked the best and with the right balance I don't have to take an anti-histamine with my food.
WHAT I LOST
With this complete change of diet I now do not have to take any of my former medications like, ranitatine, omezaprazole, tums, eye drops, nasal steroids, Ibruprofen, dramamine.
All my symptoms have disappeared like sneezing, coughing, eyes hurting, sensitive teeth, nasal inflammation, bloating, acid reflux, no skin rashes, white tongue, mouth ulcers, stomach pains, blurry eyes, sore arms, dizzyness, headaches, extreme, debilitating fatigue,
WHAT I GAINED
At one point I dreaded food, I became scared of it knowing I had to eat, but my body would attack me everytime I did. It was hard to tell the difference between the flu and an allergy attack.
But, with a completely changed diet, I've regained my energy and my life back. I have considerable regard for my body and immune system as I've learned the hard way it always has the last word.
OBSERVATIONS
I notice that my allergies can change. At one point I could eat avocado, banannas and carrots and now I can't. But, I also noticed that with a good helping of pickled condiments I can eat a quarter of a slice of whole wheat bread and a wee tootsie roll without ending on the floor clutching my eyes.
Someone I spoke to said he ended up in hospital for a couple of weeks due to food allergies. His symptoms infected his lungs and respiratory system. After his stay he went on an exclusive diet of just roast chicken for an entire year. He was then able to gradually re-introduce other foods back into his diet. We both agreed how toxic, poisonous some foods can be and he like me he is careful what he re-introduces back into his diet. No one wants to end up like some folk with such severe food allergies they eat only through an IV.
Gosh, I hope some of this helps.
I don't know if a lifetime of eating mostly carbs and sugar triggered this later in life, or just getting older, or living near too much traffic, but I certainly would not wish it on anyone.
Cheers!
Saving 
