Paying people to lose weight works: Study

Participants in rewards group closer to goals than control group, say Duke-NUS and SGH

A new study has found that paying people to lose weight works like a charm.

It does not even take a lot of monetary rewards, researchers found, for people to feel the satisfaction of meeting their goals.

In the study, 161 people paid $234 to join an intensive weight loss programme at the Singapore General Hospital (SGH) for four months. Participants were given a step tracker and had individualised exercise and meal plans.

On top of that, some paid $165 for a rewards programme, to earn cash for meeting certain weight loss goals.They could also opt for a lottery ticket instead of cash, which would give them a one in 10 chance to win 10 times the cash payout.

After four months, researchers found that those in the regular weight loss programme had lost an average of 1.4kg.

On the other hand, those who had also joined the rewards scheme had lost 3.4kg on average.

This difference in weight loss was observed up to eight months after the programme had ended.

The study was published in international journal Social Science And Medicine last month. It was led by a team of scientists from Duke-NUS Medical School and SGH.

Apart from losing more weight, those in the rewards scheme were more likely to meet the clinically significant goal of losing at least 5 per cent of their body weight. By four months, 40 per cent had hit this target compared with 12 per cent in the other group.

On average, people in the rewards scheme won $225 - resulting in a net win of $60. Although less than half won more than they had paid to join the scheme, eight in 10 said they were satisfied.

"Our findings not only show the value of rewards to increase weight loss and weight loss maintenance," said Professor Eric Finkelstein, who is in the Duke-NUS programme for health services and systems research. "(But) they (also) show it can be done in a manner that minimises third-party payments, such as those by employers or insurers."

The payoff in terms of health can be significant, said Dr Tham Kwang Wei, director of the Lifestyle Improvement and Fitness Enhancement Centre at SGH.

"Even small amounts of weight loss, sustained over time, confer great health benefits and can help prevent chronic disease," she said.

Sports psychologist Edgar Tham from SportPsych Consulting noted that extrinsic rewards are typically not a sustainable way of motivating people to lose weight and could even undermine intrinsic motivation in the longer term.

But he agreed rewards are a good way of kick-starting the process. "Hopefully people enjoy the activity, and then from there, the intrinsic motivation can kick in," he said.

A version of this article appeared in the print edition of The Straits Times on June 10, 2017, with the headline 'Paying people to lose weight works: Study'. Print Edition | Subscribe