Do you eat carrots? I had a yeast reaction every time when I had them. There's also the possibility that you've become unknowingly intolerant of something which is usually OK. Perhaps if you could give us a more detailed run down on what you eat in a typical day or week, we could suggest things which may be undermining your diet.
On a side note, I would just like to point out that I felt much, much better when I followed a anti-yeast diet which included a lot of meat. I still feel better while on this diet.
My only problem was the fact that I could feel better on the diet, but I couldn't break it without feeling horrible again. Chelating heavy metals from my body is what has helped me most.