My son had some problems with gas and was placed on soy, then I don't remember why, but they switched him to lactofree and he did wonderful. Sometimes it is just easier on their stomachs. He has outgrown this problem so I guess it's a wait and see thing.
my daughter was switched to soy instead of regular formula because she was constipated too much that later i found out was because she was on vitamins that had iron. but my doctor told me to give her soy . but make sure hes is not lactose intollerant. if he is, thats a different case. but as soon as my daughter turned 1, i gave her regular milk but i started with 2% because its easier on their belly than whole milk.