I know for some people choline is a problem and fish and eggs are very high in choline.
I personally don't have a problem with them but I know others do.
From my understanding some fruits, vegetables, chicken, and white rice are best. But even chicken, and some fruits can be a problem.
I would eat leafy greens, white rice, and low Sugar fruits for a while. Then slowly add in other fruits, veggies, and meat one at a time to see if you'll have a prob with them.