As for so many other people here only getting around a 1,000 calories a day, why do you think they are still sick?!
I think the answer for you is just too simple for you to believe.
How about this, try my advice for at least a couple of weeks and start a blog about it here. Track and post what you're eating so everyone can see. If my theory is correct, you will finally start to feel better. If not, then you can show everyone how wrong I was.
It will be a win-win for you and at this point, you have nothing to lose and everything to gain.