While it is true that those who have a strong willpower or self control often lose more weight, a new study has found that people can learn to increase their self control.
The Miriam Hospital's Weight Control and Diabetes Research Center team found that individuals with more willpower - or self-control - lost more weight, were more physically active, consumed fewer calories from fat and had better attendance at weight loss group meetings.
The same was true for participants who experienced an increase in self-control during a six-month behavioural weight loss treatment program. Results of the study are published online by the journal Obesity Research and Clinical Practice in advance of print publication.
While the findings may seem obvious, lead author Tricia M. Leahey, Ph.D., of The Miriam Hospital's Weight Control and Diabetes Research Center, explains there have been surprisingly few studies focusing on the impact of self-control on weight loss.
"Of course it makes sense that if you have more 'willpower' you'll do better in a weight loss program; however, this phenomena is surprisingly understudied," she said.
"Our study is the first to examine whether practicing acts of self-control during weight loss is linked to an increase in self-control and better weight loss outcomes, although other research has demonstrated this effect in the area of smoking cessation," Leahey said.
Leahey added that the current study suggests self-control, or willpower, is like "building a muscle."
"The more you 'exercise' it by eating a low fat diet, working out even when you don't feel like it, and going to group meetings when you'd rather stay home, the more you'll increase and strengthen your self-control 'muscle' and quite possibly lose more weight and improve your health," Leahey said.
Leahey led two preliminary studies to examine the role of self-control in a behavioural weight loss treatment program.
The first study involved 40 individuals participating in a six-month behavioural weight loss intervention. The intervention included weekly sessions led by dieticians, exercise physiologists and/or behavioural psychologists, as well as private weigh-ins.
All participants were given a reduced calorie, low-fat diet; a physical activity prescription aimed at increasing their activity minutes; and instruction in behaviour change strategies, such as relapse prevention.
At the end of the session, researchers tested participants' global self-control with a handgrip task, a commonly used tool that measures how long participants can hold onto and squeeze a handgrip.
During the task, participants experience "aversive stimuli," such as cramping, pain and discomfort, and have to override the desire to end the uncomfortable task in order to achieve their goal, which was to squeeze the grip at a certain intensity level for as long as possible.
The second study extended the findings of the first by examining whether changes in self-control were associated with treatment adherence and weight loss outcomes.
23 participants enrolled in a six-month behavioural weight loss program similar to that in the first study, and completed the same objective measure of self-control - this time at both pre- and post-treatment.
Researchers found that participants in both studies who achieved a 10 percent weight loss - which can reduce the risk of heart disease, diabetes and other illnesses linked to obesity - had greater self-control compared to those who did not achieve such a weight loss.
Also, individuals in the second study who demonstrated increases in self-control from pre- to post-treatment achieved a significantly higher weight loss, attended more group meetings, engaged in more minutes of physical activity and ate a healthier diet.
"Our findings suggest that self-control is potentially malleable and the practice of inhibiting impulses may help people lose weight, eat healthier and increase their physical activity," she said.
"Future weight loss treatments may consider targeting self-control, or willpower, as a way to enhance outcomes," she added.
The study has been published online in Obesity Research and Clinical Practice.