If the long-term health benefits of weight loss do not inspire people to diet and exercise, some immediate financial incentives just might, a study published Tuesday suggests.

The study, which enrolled 57 obese adults, most of whom were men, found that those given financial incentives to shed pounds lost about three times as much weight as those whose sole incentive was a monthly weigh-in.

Over 16 weeks, subjects in one of the two incentive groups lost 13 to 14 pounds, on average, compared with 4 pounds of those in the weigh-in group.

At the end of 7 months, both incentive groups regained weight, making the difference between these subjects and those in the control group no longer statistically significant. However, the subjects in both incentive groups still maintained a net weight loss after 7 months compared with their weight at study enrollment. In contrast, this was not observed in the control group.

The findings, reported in the Journal of the American Medical Association, suggest that where promises of better health fail to motivate people to lose weight, financial rewards might succeed.

The idea, lead researcher Dr. Kevin G. Volpp told Reuters Health, is to address a fundamental obstacle to making healthy lifestyle changes: People just don't like to give up the things they currently enjoy — like eating sweets or smoking cigarettes — for a potential health benefit down the road.

"The notion that there will be some reward in the future is easy to ignore," noted Volpp, an associate professor at the University of Pennsylvania School of Medicine and staff physician at the Philadelphia VA Medical Center.

The prospect of gaining or losing money in the short-term, by contrast, is hard to ignore.

For their study, Volpp and his colleagues used two types of financial incentives. In one, study participants were eligible for a daily lottery prize, but could collect their accumulated winnings only if they met their weight-loss goal at the end of the month.

The other incentive program involved a deposit contract, in which participants could contribute up to $3 per day and have that money matched by the research team. Again, they could collect the money accumulated only if they met their weight-loss goal at the end of the month.

All of the study participants were randomly assigned to one of the incentive groups or to a control group that had only monthly weigh-ins. Participants in each group were given a goal of losing 16 pounds over 16 weeks.

Overall, the researchers found, the two incentive groups lost significantly more weight, on average. And while roughly half of each group met the 16-pound goal, only 10 percent of the control group did.

In real life, similar financial incentives could be offered by health insurers or employers, Volpp said. Their incentive, he noted, would be to improve the health of health-plan members and employees, thereby driving down their healthcare costs.

Volpp also noted that the current system of healthcare doesn't offer any incentive to practice healthy behavior.

However, he said, the current study is only a "first step" toward using financial incentives to encourage weight loss or other healthy lifestyle changes. More research is needed to see whether money motivates people over the long term.