People who regain weight after dieting are not failures. But if they see themselves as failures, they may be more likely to regain lost weight.

Regainers tend to have an "all-or-nothing" style of thinking, according to research by psychologists at the University of Western Australia. They see themselves as either a success or a failure, with no options in between. People who keep weight off seem to allow for more shades of gray.

Most people stop losing weight after about 20 weeks of dieting. If an all-or-nothing thinker hasn't reached her goal weight by then, she may see herself as a failure and give up on her new eating habits, surmise Susan M. Byrne and colleagues.

An "all-or-nothing" mind-set has also been associated with suicidal tendencies and chronic pain, among other problems.