I have the same issue. It's common in older people.
Try cutting out the bread, pasta, crackers, cookies, donuts, cake, cereals, wheat containing snacks & foods, processed high carb foods, etc.
Cut out or reduce as much as possible junk food.
Eat meat, fish, eggs, cheese, milk, butter, oils, vegetables, oatmeal, some fresh fruit, natural peanut butter.
Also a good idea to eat smaller portions of the food you do eat so you don't stretch your stomach.
Take a psyllium fiber supplement everyday like Metamucil. You'll take big shits and clean out your bowels.
Another thing you can try is intermittent fasting a few times a week. Basically don't eat from 8 PM to 12 Noon the following day. 16/8 fast.
It gives your stomach a break.
This being said, if you are messing yourself up taking steroids that is something you should stop doing.