I saw this on yahoo today & thought it was an interesting article:

The Science Behind Healthy Weight Loss

Control the amount of calories you eat, and fill your plate with lean protein-rich foods, fruits, vegetables and whole grains.

Fad diets, such as those that severely restrict carbohydrates while plying you with protein and animal fats, may well work for a while, but it doesn't take much snooping to figure out why: They're low in calories. And lowering calories will lead to weight loss, no matter the quality of the diet. But is this a diet that's built to last?

The ongoing challenge is to keep calories under control while enjoying satisfying portions of healthy foods. For that, you can't get around the importance of a diet that's:
- Low in fat
- Adequate in protein
- Rich in high-fiber complex carbohydrates

We'd all love to believe that the latest fad is the one that's going to miraculously remove those unwanted 20 pounds for good. But we're better served by relying on proven choices than pie in the sky. Our best allies are low-calorie foods that are naturally filling: lean protein, low-fat dairy or soy foods, whole grains, and plenty of fruits and vegetables. All skimp on fat, and all are swimming in water and fiber, which stimulate "satiety signals" - they make you feel satisfied without adding calories.

The Lowdown on Fat, Protein, Carbs and Water

Fat
Gram for gram, fat has more than twice the calories of protein or carbohydrates. Excess calories from fat end up as body fat far more easily than excess calories from carbohydrates or protein. Your body has to work to convert carbohydrates or protein to body fat, which takes energy - that is, it burns calories. But dietary fat turns into body fat with very little calorie loss. That's why it's important to cut calories from fat.

Protein
Eating lots of protein isn't a recipe for losing more weight, though getting enough protein is important. When you cut calories to lose weight, your goal is to lose body fat, not lean body mass (muscle). Taking in enough protein helps you maintain lean body mass. Protein is also more "satiating" than fat or carbohydrates, so it helps you feel full on fewer calories.

Carbohydrates
No, pasta isn't uniquely fattening. Neither are potatoes, rice or bread. It's true that many overweight people have difficulty metabolizing large amounts of carbohydrates, but that's an effect of their physiology, not a cause. The cause of obesity is too many calories and not enough exercise. Focus on carbohydrate quality: Refined snacks and sweets made with white flour and sugar are highly caloric, while fiber-rich whole grains, fruits and vegetables are much more filling, with fewer calories.

Water
Let the water flow freely in a weight-loss diet. Besides drinking lots of it, eat plenty of foods that are naturally rich in water, such as fruits, vegetables and low-fat milk. Pair them up with poultry, fish and beans - all low-calorie foods that provide plenty of bulk.

Keep a place in your diet for water-rich dishes like soups, stews, casseroles, pasta with plenty of vegetables, and fruit-based desserts. Water helps you control calories by diluting the calories in a portion of food. When you add water-rich blueberries to your breakfast cereal, or water-rich eggplant to your lasagna, you add food volume and weight, but hardly any calories.

Estimating Calorie Needs
The average, moderately active person needs about 15 calories per pound to maintain weight. For instance, to maintain a weight of 150 pounds, you need about 2,250 calories a day. However, this is just a rough estimate. Your true caloric needs are more closely linked to the amount of fat and lean tissue you carry. A well-muscled 150-pound wrestler burns more calories than a 150-pound couch potato, even on days when the athlete decides to kick back and grapple with the remote control.