What people who have already lost the weight and kept it off say

In Tips for Successful Weight Loss, a study details the success habits of people who have lost at least 30 lbs. and kept it off for one year. The most surprising factor to me was the average caloric intake of 1,400 calories. That seems like very few calories to me. I also founded notable that the participants did not participate in diets like the Atkins Diet or South Beach diet.