Any successful weight-loss program, including those using bariatric surgery, must include a psychological component. Everyone's reasons for gaining weight vary, but often emotional eating or another emotional issue is a factor. Whether your tendency to overeat is due to a lifestyle change, boredom, stress, loneliness, or other factors, something caused you to gain weight. Embarking on a weight-loss program without addressing the underlying reasons for the weight gain is setting yourself up for failure. Even people who have had bariatric surgery sometimes regain the weight if they don't address their reasons for their weight gain in the first place.