Cooked food after a fast won't reverse the effects. Technically it won't anyway. This is often said but it is physically impossible. Just think, it is possible in a few weeks to throw off the accumulated toxins stored up over decades.. to undo that work in one more day of eating? I don't think so. The danger is that you could absorb more toxins after fasting because your digestion system is clean, empty, and better able to absorb anything put into it than at any other time- nutrients or toxins! So whatever we put back in during the refeeding will do more good and/or damage than it normally would. Also cooked food, and more so artificially created and processed foods, can have more concentrated elements added to them than occurs in nature. And if we add too much of anything too soon after a fast there is a chance we will overload the system which needs time to return to it's full capacity, or full speed let's say. We get so used to overeating or eating unnaturally highly concentrated foods we take it for granted but they really are a burden on the system and attempting to do this after a fast can literally shut down our body and be fatal.
If you end a fast with cooked veggies, stewed fruit or broth say, the damage if any won't be as serious from toxins but the benefits won't be as great as with naturally water and nutrient rich raw fruits. I hope this answers your question.