Lose the kilos with cash rewards
2008-12-10 10:19
Chicago - Losing weight is easier
when there is money on the line, US researchers said on
Tuesday.
They said weight-loss programmes that reward people with
money - and remind them of the cash they stand to lose if they
fail - provided a powerful incentive to lose weight compared
with more conventional approaches.
Dr Kevin Volpp of the University of Pennsylvania School of
Medicine was looking for an effective way to treat obesity, a
growing problem that carries serious health risks.
He said many weight-loss programs fail because people are
being asked to make sacrifices now for rewards in the future.
"We wanted to create a reward system which gave them
rewards in the present," said Volpp, whose study appears in the
Journal of the American Medical Association.
Volpp and colleagues studied two kinds of incentive
programmes for weight loss. One was a lottery-based design in
which participants played a lottery and were allowed to collect
their winnings if they met their weight-loss target.
Weight-loss target
The lotteries were running daily, and people were told what
their winnings would have been if they had met their
weight-loss target.
"There is a very strong sense of loss aversion," the theory
that people are highly motivated to avoid losses, Volpp said in
a telephone interview.
"The idea was to create a mechanism where loss aversion
would help drive people's motivation," he said.
The other was a deposit contract, in which participants
invested a small amount of their own money - between 1 cent
and $3 per day - which they would lose at the end of the month
if they failed to reach their goals. People in this group also
got a bonus if they met their goal.
"You only received your reward at the end of the month if
your weight was below the stated goal for the month," Volpp
said.
Incentive groups
The researchers assigned 57 obese but otherwise healthy
people to one of these two groups or a control group, in which
people were simply weighed at the end of each month. All were
aiming to lose 7.26kg by the end of four months.
People in the incentive groups lost far more weight than
those who got no pay for their efforts, with about half of the
participants in each group meeting their weight loss goals.
People in the lottery programme earned a total of $378.49 and
lost about 5.9kg, while people in the deposit
group got $272.80 and lost 6.35kg.
Those in the control group, who were merely rewarded by
better-fitting jeans, lost about 4 pounds after four months.
Volpp said the studies were highly effective at producing
short-term weight loss, but when the money stopped flowing, the
weight began to creep back on.
"We need to establish whether they can be effective in
sustaining weight loss as well," he said.