I use an ab roller 3 times a week, but i still have a little stomach fat at 155 lbs. what else can i try?

Abdominal Fat: For a flat abdomen eat healthfully ; be physically active. Calories burned must > calories consumed. To tighten ab's do crunches, reverse crunches, exercise ball crunches, pelvic thrusts, lying leg raises, side bridge ; “bicycling” exercise on your back. Engage in regular aerobic exercise (i.e., running, swimming, nordic track, bicycling, kickboxing, walking, cross country skiing, hiking, etc.).