Hi there I was/am like Gigi...Allergic to literally EVERYTHING. I was on IV nutrients for over a year because I literaly could not eat at all...yet I tested allergic to nothing when I had a blood type allergy test done by my LLMD...yet obviously something was not allowing me to eat.
There is a difference between allergies and food intolerances...You may or may not be having a antigen/antibody mediated response...if not...the tests won't show anything...You may have an antibody response to some foods (a true food allergy) and "just" food intolerances to other foods...which can be anywhere from benign reactions and easily ignored, or can cause severe reactions just like anaphalaxis (sp?)type allergies, so they should not be underestimated.
Also if you weren't exposed recently to the food you are allergic to, due to avoidance, good chance the test will show negative as well. When I had the test done, I had already stopped eating for several weeks, and ate only minimally for several months prior to that...so any antibodies they were looking for, had already probably gone away, which they will do if you are no longer explosed to the food for a period of time...
I finally got my answers when I got energetically tested for allergies through a Bioset practitioner...and it showed I was even "allergic"/sensitive to the pure individual nutrients in my IV...which mainstream docs would tell you is impossible, but it sure explained a lot(why I could only tolerate 500 calories a day spread out over 24 hrs or I became completely debilitated)
With Bioset, I have slowly been reversing the allergies...which includes acupuncture, gentle detox methods, and energetic clearings of the blockages that caused me to develop the allergies...
Before Lyme, I never had a single allergy...at least nothing that stopped me from eating...so Lyme(and/or its toxins) can do this to us...I am convinced of this...but in hindsite, I like you, always had bouts of constipation and digestive issues (trouble with dairy and lipids)...was born with severe colic which could just make my digestive tract a weak zone for the lyme to have gone to perhaps...??
Also, the allergies can fluctuate depending on what organ system is being blocked or overloaded at any given time. If you notice allergies early enough, following a rare foods diet, or the four day rotation rule should help, and many reverse their problems this way just by relieving the stress off the body from constant inflammatory responses...but I didn't catch it early enough or make the connections that I was so toxic, that I ended up basically with the food version of MCS...got to the point if food even touched my lips, I would literally pass out. It was real bad there for awhile...
Even now, after having cleared many of my "allergies"...I will still have trouble tolerating them if I am in the midst of a herx, or try to detox myself a little too enthusiastically...Seems to be this fine balance...and when my body is having to deal with more toxins than usual, it immediately gets overloaded, and I can't tolerate foods again...so if you notice some days you can eat or tolerate a food and the next day you can't...this could be why for you too...
Well, I am far from an allergy expert, but sure had more than my share of experience with allergy problems...so hope what I shared is of some help to you...
Since you are in Illinois also, e-mail me if you would like the name of a Bioset practitioner...She's in Dekalb (Near Northern Illinois University) I travel over an hour to see her, but it's been worth it!! I'm eating again!!
All my best,
Kira