Yep. I have experienced this with a cookie, but I can eat plain vanilla ice cream without a problem, or just raw sugar. So I think its not as much the sugar but what other things that are in it like the oils/flour. If I eat like..uhh anything fried at a restuarant almost instant pain. This contains both bad oils/flour. If I eat a brownie, pain canola oil/flour. If I have salad dressing with soybean oil in it... I dont really get any pain but dont feel as good as normal. If I eat a small piece of bread (like the same size as that brownie).. I'm Ok. But on thanksgiving I had loads of sweet potato pie (it was crustless) that I believe contained a trace amount of oats and def lots of brown sugar and I was fine. I had a cup of brown rice and was in pain for hours tho.. So it seems to be when certain things are in combination for me, it also seems to depend when I consume them. Ice cream after a 4 mile bike ride..not so good. Ice cream after relaxing eating no problem. I think it also may depend on the other things I'm eating at the time. Empty stomach, full stomach with lots of protein.... lots of fat..
It certainly makes you less tolerant to these toxic things in general.
Primal since March 2011
Female/29 years old/5' 1"/130ish lbs