For BMs Mangoes work the best. But if you do not want to put too much Sugar in your body then let it be. I also like lemonade with Himalayan salt and honey.
Have tried coffee enema? You should give it a go. I did one on my second day of fast and I was energized. Yes, fasting is very easy for me. In five days I have lost 8lbs. My mental clarity did not have problems, but it has improved. I am working and hopefully get me to the weekend. I intend to do 7 days, 10 would be even better.
So going weight issue has to causes, one eating more than we should and not expending the calories we take in. Ayurveda says that one should stay a little bit hungry and not fill up the stomach totally. It also says eat as much that fits in your two palms put together.
A good thing is you are exercising. I usually gain 1lb a day, too, but don't exercise as you do.