The National Institute of Health teamed up with the Harvard School of Public Health and the Pennington Biomedical Research Center at the University of Louisiana, Baton Rouge to track the progress of 811 overweight people on four different types of diets. Each diet featured a different ratio of fat, carbohydrate and protein content and the meal plans' total caloric intake typically fell in the range of 1,400 – 2,000 calories, depending on individual needs. After two years, the study found that the participants' average weight loss of 9 pounds and average waist loss of 2 inches was the same across the board no matter which of the four diets was being followed. Conclusion: It all comes down to the calories.