There are literally hundreds of diets available. Moving from diet to diet in a cycle of weight gain and loss - yo-yo dieting - that stresses the heart, kidneys and other organs can also be a health risk.
Ninety percent of people participating in all diet programs will regain the weight they've lost within two years.
Behavior modification uses therapy to help patients change their eating and exercise habits. Diet and behavior modification are instrumental to sustained optimum fitness levels and weight loss.