Ender has a good point about the liver and pancrease. Especially the liver, if it becomes 'fatty', it will add to the body weight.
Also, if you are on more enzymes, then the intestinal tract may fill up more than it used to with less enzymes. Also, your weight gain may be due to the enzymes working, and taking more nutrition out of the food eaten.
I actually had spent the last ten years becoming malnurished, and when I finally was able to eat what I wanted (and what I needed), my weight increased tremendously, but I also felt bloated quite often.
Perhaps your body needs a little time for the adjustment on the increase of enzymes? Just a thought (and my two yen!).