Researchers found that people paid to trim down lost more weight than hefty employees who had not been given a financial boost to get fit.
"We had a few people who lost a lot of weight," said Dr. Eric Finkelstein of the non-profit research organisation RTI International in North Carolina.
He and his colleagues divided 207 people, who had an average weight of 200 pounds (91 kilogram’s), into three groups to compare their weight loss.
The first group were not offered any financial incentive to slim down. But the second group received $7 for every percentage point of their body weight they lost, while the third group was offered $14.
The researchers, who reported their findings in the Journal of Occupational and Environmental Medicine, discovered that after three months people in the $14 group lost an average 4.7 pounds, compared to three pounds in the $7 group. People who had not been paid lost about two pounds.
"The big finding ... is that there are a few people who you can really (help to) improve their health and these are the ones who are most cost effective to target," said Finkelstein.
He added that people in the $14 group were more than five times more likely to lose a clinically relevant five percent of their body weight.
Statistics from the North American Association for the Study of Obesity show that more than 64 percent of adult Americans are either obese or overweight. Companies are feeling the impact through higher medical bills and absenteeism, according to the study.
Some firms offer options like an in-house gym to encourage employees to be healthier, but Finkelstein is sceptical about putting money into high-cost, one-time strategies. He argues that it does not guarantee results and is not as cost effective.
"The beauty of incentive based strategies is they're essentially costless. If nobody changes behaviour, you don't pay anybody money."