Following is an article written by Mike McLaughlin and Carol B. Suter, MS, RD, LD, CFCS which appeared in National Bodybuilding and Fitness Magazine
Most bodybuilders do not spend ten years of their life building muscle, then several more trying to lose dozens of pounds of fat. Quite the contrary, the more muscle you build, the easier it is to -burn- fat, because of your elevated RMR. A person with a lean body mass of 180# for example, has a RMR (resting metabolic rate) of around 2400 calories. It is very easy to ingest the 90-100 grams of protein this person would need to build muscle, in addition to needed carbohydrates, yet remain under their 2400 calorie limit. This does not even include calories burned off during exercise.
It is, always has been, and always will be a mattar of simple arithmetic. You -must- stick with foods high in protein and low in fat. You can not eat a steak for breakfast and dinner, and a dozen eggs in between if you want to lose fat. You will gain muscule, but you will gain a lot of fat with it. Stick with things like fish (one can of tuna has 30 grams of protein and less than 2 grams of fat). You cannot expect to eat a gourmet diet if you are serious about bodybuilding, it may not taste good, but then again you are not in it for the choice of cuisine!
You are probably aware that appropriate exercise and eating according to the Food Guide Pyramid daily can also increase your energy level and help you to lose weight. As others have already said, its important to eat enough of the nutrient dense foods that are low in fat so that you won't be craving or wanting to eat very much of the empty calorie foods. I couldn't agree more with those who have stated that you should never tell someone that a food is forbidden as psychologically, they'll want it all the more. There are really no bad foods. There are just foods that we need to eat in smaller amounts than others, always try to balance the high calorie foods with the lower calorie ones and have enough daily exercise. You know that if you want to lose weight, you have to expend more calories than you eat. You must burn or expend 3500 calories to lose a pound of body fat. You may want to envision that as a l pound carton or margarine or butter attached to or detached from you. However, we haven't accumulated that fat all in one place on our body - it can even cause you to wear a wider size shoe.
To get weight off and keep it off, its very important to exercise regularly and to do so with a well balanced diet that you can maintain for a lifetime and not become bored. Its when one doesn't take time to exercise some and eat healthy is when one is tempted to grab some candy bars, chips, and/or soft drinks and get into a mode of eating too much of the high sugar and fat-rich foods. Then the energy level drops quickly and one wants more. Its important to get into the habit of keeping some nutrient dense vegies, fruits, and low fat bread and protein-rich group foods on hand for quick snacks if your regular mealtime must be delayed. Just remember balance, variety and moderation!