All of the ingredients you mentioned are grains (except potatoes) and I found out even a little bit is not tolerated. I am avoiding potatoes also, but you may not have to. I stand in the store and read labels. Most of them will not work. I also have some supplements which I get from my chiropractor. I have to scrutinize the ingredients there also. I have been ordering some of my supplements from Dr. Osborne. I order them online. I know there should be no grain in them. I still have to read labels.
I hope you do find good supplements as supplements saved my life.