NO CRUNCHES….AEROBIC EXERCISE/CARDIO ONLY. As mentioned by @Jayy…abdominal exercises makes your abdominal muscles bigger. All of the people I see at the gym using the ab machines will actually make themselves thicker unless they do some aerobic exercise to burn the fat. Most people already have good abs because they are one of the principle sets of muscles that is involved in almost every movement we make during the day. @Jayy mentioned cardio, which is aerobic exercise. Don’t worry about crunches or ab exercises. If you do some speed walking or slow jogging, you will be exercising your abs. Try to reduce the amount of fat and carbohydrates that you eat and replace these with complex carbohydrates. If you can reduce the amount of sugar, bread, pasta, potatoes, and desserts, you will do yourself a huge favor. Also, portion control is important. One serving is about the size of your fist, not more. Try to have more steamed veggies (not too soft) like asparagus, zucchini, squash, green beans which provide vitamins and fiber, but not that many calories. Try not to put butter on them! You can also bake beets wrapped in foil in the oven at 400F for 45 minutes, then skin them, cube them, and pour balsamic vinegar over them. These are great for fiber and antioxidants. Then choose lean proteins – chicken, turkey, tuna, egg whites, lean pork or ham.