Why Does Rebound Weight Gain Happen After Weight Loss?

Obesity and weight management have become a national obsession as Americans pack on the pounds. In fact, obesity has been officially declared a disease by the American Medical Association. Losing weight is a challenge, but keeping it off once you've met your goal can be even harder. Understanding why weight regain occurs is the first step in devising a strategy to maintain your hard-earned results.

Lifestyle and Behavior Change

• Weight loss programs often require you to eliminate common foods from your diet and replace them with foods or supplements you would not normally eat. The problem with this approach is that once you meet your weight loss goal, you are likely to go back to your old eating patterns. Likewise, many dieters are willing to exercise to lose weight, but they stop exercising once their goal is met. Dieters who commit to long-term lifestyle and behavioral changes appear to have greater success. A long-term study of subjects who maintained weight loss after five years identified common behavioral factors that contributed to their success. They included high levels of physical activity, maintaining a low-calorie diet, monitoring weight, eating breakfast and having a consistent daily eating pattern.

Motivation and Emotional Factors

• People who embark on a weight loss program are often highly motivated. The motivation may be extrinsic, such as a warning from your doctor, or it may be intrinsic, such as a desire to look great for an upcoming class reunion. You may be willing to do whatever it takes to achieve your goal, but once the goal is met, motivation dwindles, and old habits creep back in. Emotional issues may also play a role. A 2005 study in the "American Journal of Clinical Nutrition" pinpointed depression as an indicator for weight regain. The same study found that individual levels of self-control were key to maintaining weight loss.

Physical Activity

• When dieting, loss of muscle mass can account for a significant amount of your weight loss. While losing muscle may help you achieve your goal, it can lower your basal metabolic rate, or BMR, which determines how many calories your body burns at rest. Once you return to normal eating patterns, you are likely to regain weight due to your reduced BMR. To facilitate weight loss and preserve lean muscle, the American College of Sports Medicine recommends engaging in both resistance training and aerobic conditioning exercises during weight loss, and continuing those activities once your goal is met.

Hormonal Influences

• Hormonal changes after weight loss may also play a role in weight regain. A 2011 study in the "New England Journal of Medicine" found that hormones responsible for suppressing appetite were reduced in subjects who lost weight, and that the lower levels persisted after one year. In other words, subjects had a greater appetite after weight loss, which contributed to weight regain. A "Clinical Science" review of studies, published in 2013, noted that in the section of the brain called the hypothalamus, there are hormonal signals from sites like the gastrointestinal tract and fatty tissue that conspire to increase appetite and decrease physical activity after weight loss.