"The four basic components of a safe and successful weight management program are: healthy eating habits, behavior change, exercise, and weight maintenance," said Pearl Voce, a clinical dietitian at Holy Cross Hospital.

The main thing teens should change about their eating habits is the calorie intake, Voce said. All foods have calories, but it's the extra calories that become fat. She recommended that people read labels and try to eat foods that have less calories because starvation diets are ineffective and unsafe.

"Aerobic exercise is the perfect partner to a weight management diet," she said. "Aerobic exercise involves the continuous use of the large muscles of the body.