It is NOT possible to spot reduce body fat.

Fat is spread throughout the body, therefore whenever you burn fat you will burn it from fat deposits all over the body.

Men will typically lose the fat around their midriff and under arms last, while women will typically lose fat around their hips and thighs.

Doing crunches will build your abdominal muscles, but if your body fat percentage is not low enough you will not be able to see your abs.