When it comes to slimming down for good, the initial weight loss is the easy part. If you want to maintain your weight loss for life, the odds are stacked against you. According to Gary Foster, Ph.D., clinical director of the Weight and Eating Disorders Program at the University of Pennsylvania, 65 percent of dieters return to their pre-dieting weight within three years.

The reason that most people regain is that they focus too much on learning new eating and exercise habits during the weight loss period, and they spend virtually no time understanding the mental and emotional challenges that caused them to gain weight in the first place.

The story of David Smith is a classic example of how dangerous it can be to not address the mental challenges of weigh loss. David lost 400 lbs from his high of 650 lbs. He appeared on the Today Show to reveal his new body, and he even became a personal trainer.

David regained 250 lbs in a year because he did not fell comfortable in his new body. His new identity as a role model on the outside didn’t fit with his discomfort on the inside. He started eating in secret, and felt like a failure when the weight started coming back on. Check out his story:

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David is not alone in his struggle. While there is no shortage of diet and fitness advice to help people learn how to change their nutritional and exercise habits, weight loss solutions are typically not coupled with psychological support to help people identify self-sabotaging behavior and thought patterns. Psychologists are becoming increasingly interested in studying why people regain. The results of their studies are shedding new light on behavioral therapies that can help people maintain weight loss for good.

In a study conducted on fifty-four women with obesity in the UK, psychologists have discovered two factors that contributed to weight regain. The women in the study lost weight by attending diet support groups, and were interviewed immediately after losing 10 percent of their initial body weight. Psychologists followed-up every two months for one year via telephone interviews.

Two factors measured immediately after weight loss were identified as significant predictors of weight regain at one-year follow-up:

Black and white thinking – defined as “all or nothing” thinking. People who have this attitude think like this: “Either I am at my goal weight, or I have failed,” or “I just slipped up and had one cookie, so I might as well have the whole box since I have already failed”. By giving themselves no room to have an occasional cheat meal, or time to move through a weight loss plateau, black and white thinkers are more likely to give up and regain weight.

Maximum lifetime weight – the higher the starting weight, the more likely a person is to regain at least some weight. Scientists believe that this has to do with the body’s set point weight. People who have high starting weights have bodies that are used to being larger, so homeostatic processes in the body want to get the weight back to where it used to be after weight loss. Hormones have been used to dealing with a larger body for so long, that they signal the body to start eating more and storing more fat because the body senses that it is starving, even when that is not the case.

Psychologists have identified a few additional factors that predict weight regain:

Having unrealistic weight goals.

Poor coping or problem-solving skills.

Low self-esteem.

On the other hand, psychological traits common to people who experienced successful long term weight loss include:

An internal motivation to lose weight.

Strong social support.

Better coping strategies and ability to handle life stress.

Autonomy and assuming personal responsibility in life.

Have you ever struggled with the mental challenges of weight loss? If so, how did you overcome your obstacles?