In one sentence, describe what the following article is about:

Fewer calories in equals more calories lost. More calories lost equals a smaller everything--including your bottom. Cutting calories with exercise may not be enough; you have to monitor your eating habits, too. 1 pound is 3,500 calories. If losing 10 lbs is your first goal, cutting 500 calories a day will equal the loss of 1 lb per week, 10 weeks in total. But don't forget: Exercise cuts out calories, too. So often carbs and fats are made into villains. However, there are good carbs and good fats that are very important to your diet; they give your body energy, maintain your metabolism and help your digestive system absorb vitamins. Avocados, olives, nuts, olive oil and salmon all have good unsaturated fats that will keep you satiated, which will keep you from overeating later. Whole-grain and whole-wheat breads, cereals and pasta, oatmeal, couscous, quinoa, and brown rice are good carbs that provide fiber, energy, and keep your insulin levels normal. Both of these food groups help you build muscle and are full of nutrition. Dairy and protein will also make it easier to get through your workouts. Eggs, turkey, chicken, fish, low-fat yogurts, milk, cheeses, and cottage cheese are all good options. If you opt for red meat, make sure it's lean.

Summary:
Cut calories. Eat the right carbs and fats. Get a healthy amount of dairy and protein.