Cash incentives and motivational texts could help obese people lose four times more weight, trial finds

Obese people could be helped to lose four times more weight if they are offered cash incentives and sent motivational text messages, a new trial has found.

Participants in the study who were given both lost almost 5 per cent of their body weight on average, whereas those offered neither lost just over 1 per cent.

Described as a “win-win for all”, researchers suggested this approach could also be cheaper for the health service than traditional weight management programmes as it requires less staff, and could help reach people from more deprived areas.

They said the method was inspired by behavioural economic theory, which proposes that people are more motivated by the prospect of losing money than the prospect of gaining money.

The year-long study – known as Game of Stones – included 585 men from Bristol, Belfast and Glasgow with an average body mass index (BMI) of 37.7, who were split into three groups.

One of the groups was told £400 was being held for each of them in an account and would be transferred over at the end of the trial. However, money would be taken off the total if they failed to meet weight loss goals.

The group were also sent daily texts that included motivational messages, tips on lifestyle changes, links to information online and access to a study website on weight management with information about local services and an online tracker to monitor changes.

The second group was sent the same messages but with no financial incentive, while the third group was only granted access to the weight management information.

Some 426 men included in the study logged their weight after 12 months. Those in the financial incentives group lost 4.8 per cent of their body weight on average, compared to 2.7 per cent in the group who were sent the same messages but with no financial incentives and 1.3 per cent in the third group.

Professor Pat Hoddinott, of the nursing, midwifery and allied health professions research unit at the University of Stirling led the study, which has been presented at the European Congress of Obesity (ECO) in Venice.

She said: “Not everyone can afford to deposit their own money, so we designed the Game of Stones trial, which uses an endowment incentive, where the money is put in an account at the start, allowing men on low incomes to join.

“A text message-based programme, meanwhile, costs less and is less labour-intensive than a traditional weight loss programme.

“Men who were living with obesity helped design the structure of the incentives and helped us write the text messages.”

Prof Hoddinott also stressed the study was able to recruit people from areas “normally under-represented in weight management trials”.

She added: “Some 39 per cent of the men lived in less affluent areas, 71 per cent reported a long-term health condition, 40 per cent reported two or more long-term conditions and 29 per cent reported that they were living with a disability.

“In addition, 25 per cent of the men told us they had a doctor-diagnosed mental health condition and a further 24 per cent reported low mental health scores.”

Men included in the financial incentives group received £128 each on average at the end of the study, with 27 receiving the full £400.

Prof Hoddinott said: “We reached an underserved group of men who seldom take part in health promotion activities.

“Weight management programmes are traditionally intensive, often with a weigh-in every week or two.

“In Game of Stones, there are just four brief ten-minute weigh-ins over a year.

“No intervention is delivered by the staff at the weigh-ins, so minimal staff training is required.  No referral is needed to join.

“Men and NHS staff really valued this low-burden approach and it has the potential to address health inequalities. It was a win-win for all.”