I was using carrots as one of my primary gutloads until i noticed my chams neck starting to get a little loose/puffy. Did some do-it-yourself reaserach and learned that carrots are indeed, terrible for chameleons due to extremely high vitamin A content, which will lead to gullar edema. It can, and has sucessfully been reversed by changing my inadequate gutload recipes. I would also recommend shying away from providing your cham this veggie as well. As for me... that was a serious scare and i will never include carrots in ANYTHING that has to do with my cham from this point on.
Cute story tho, these little critters are facinating and i love em more and more everyday!