Hi Vixen -
Sure, foods can cause all sorts of allergy symptoms. We notice it in little kids, but adults can come up with new allergies at any time. It took me many years to realize that the tachycardia and arrhythmias my heart was having were triggered by foods my stomach and esophagus didn't like. Corn starch is contaminated with sulfite during processing. I can eat corn with no trouble though.
You might try double rinsing your laundry, using fragrance-free fabric softener, or none at all. The same for detergents. Try a liquid with no fragrance or colors.
You can try using only a little mineral oil without additives after showering instead of lotions. A couple of drops will do instead of hair conditioner too.
Don't forget eyedrops if you use them. Find some that are preservative-free. I use one called Genteal over the counter. Generic patanol has preservatives but seems not to give me problems for short-term use. It's preseciption here.
Even vitamins, allergy medicines, prescription meds often have preservatives and toxic dyes. I have to look out for yellow #5. The "azo" dyes are often toxic, but the "lake" dyes aren't so bad.
This year I developped a new allergy to grass pollen. My allergist has added it to my shots and I have no more trouble with it now.
Try allergy meds that don't make you sleepy. Loratidine is the ingredient in the one I like. Again, even liquid Benadryl has preservatives and colors, so watch ingredients!
Put it all in your journal! An allergist is helpful too. Mine got me tokeep the journal years ago, and it's been SO helpful!