Delayed gratification, as the name implies, refers to the ability to forgo an immediate reward (for example, delicious Cheesy Poofs) for a benefit that will come later (for example, rocking that little black dress). A lot of research shows that the better you are at delaying gratification, the better you do in life in general (you may have heard of the famous marshmallow study). To see if delayed gratification is linked to obesity, a team of researchers set out to test whether children who have a high body mass index (BMI) are less likely to delay gratification.
The researchers looked at data from an educational obesity intervention program. In this program, attended by obese or overweight children along with their siblings (the healthy weight control group), children earn a point if they complete their weekly goals. They then have two choices: either spend that point immediately on a small toy prize (like a pencil) or save the point to use later on a larger prize worth more than one point (like a basketball). The measure of points saved and points spent is thought to be a valid model of delayed gratification. So the researchers looked at the relationship between how many points were saved by a child and that same child's BMI. The results show that a higher BMI is associated with less points saved, meaning the children who were overweight or obese had a harder time delaying gratification.
The strong aspect of this study is that the rewards were not food-related. This allowed the researchers to study delayed gratification as a behavior trait in general, and not specifically as it relates to obesity. However, their sample was fairly small (59 children) and the duration of the study was fairly short (12 weeks). Therefore, it's difficult to say whether delayed gratification plays a role in weight loss.
Overall, the research is relevant in that it suggests that working on delayed gratification (it's possible to "train" to get better at it) may help in obesity interventions. And for all you out there with eat-less-exercise-more resolutions, all I can say is "eyes on the prize"...
Reference: Ability to delay gratification and BMI in preadolescence. (2010) Bruce, AS and al. Obesity [Epub ahead of print].