i mean you can.. but ask to make sure.. i know people who ate plain stuff and still passed.. but I guess it depends.. i never had protein in any of my scans with my urine and my doctor wasnt concerned with me failing the test
maybe 2 hrs before.. if u wanna call that fasting lol my doctor told me.i didnt have to.. But I had dry toast, water and boiled eggs.... 2 hours before hand then thats it.