Well boys... diet does play a role in our cholesterol, but
steroids will DEFINITELY cause a change in your cholesterol. Your liver metabolizes drugs (one function) and the drugs can cause damage to the liver, as we know... this causes the liver to be less efficient, and that's why your cholesterol is elevated. Unfortunately, that is one of the side effects that we have to live with....
Did you get other tests done too? Like LFT's? Are they up as well, or just your cholesterol?
I agree with the other guys, too, though... try and cut back on some fatty foods in your diet and food that are known for having high cholesterol. (eggs, liver, saturated fats.. etc)