If you want to achieve long-term success with weight loss, you may want to stay away from commercial diet plans – other than Jenny Craig and Weight Watchers that is. A new study published in the April 7 issue of Annals of Internal Medicine found that after examining several commercial programs, that only the two boasted scientific evidence that their clients maintained weight loss for at least a year. An interesting study published in the January 2014 issue of the American Journal of Preventive Medicine followed individuals for 10 years and determined that long-term weight loss is possible, ‘if individuals adhere to key health behaviors,’ which included physical activity, self-weighing, low-fat diets, and avoiding overeating. Both of these studies boil down to the simple notion supported by most nutritionists: if you want to sustain weight loss, you have to make permanent lifestyle changes.