Eating breakfast because breakfast stimulates metabolism and signal the body to start burning fat.
Many studies, in both adults and children, have shown that breakfast eaters tend to weigh less than breakfast skippers.
Why? One theory suggests that eating a healthy breakfast can reduce hunger throughout the day, and help people make better food choices at other meals. While it might seem you could save calories by skipping breakfast, this is not an effective strategy. Typically, hunger gets the best of breakfast-skippers, and they eat more at lunch and throughout the day.
Another theory behind the breakfast-weight control link implies that eating breakfast is part of a healthy lifestyle that includes making wise food choices and balancing calories with exercise. For example, consider the successful losers followed by the National Weight Control Registry, all of whom have lost at least 30 pounds and kept it off at least one year. Some 80% of the people in the Registry regularly eat breakfast (and also follow a calorie-controlled, low-fat diet).
It's worth noting that most studies linking breakfast to weight control loss looked at a healthy breakfast containing protein and/or whole grains -- not meals loaded with fat and calories.