Rewards are key to changing bad eating habits, study finds


A four-year study into eating behaviour among children suggests that combining a variety of strategies is the best way to tackle obesity

We are what we eat

Healthy eating campaigns aimed at children don’t succeed in changing bad habits, a group of Flemish scientists has concluded. Experts from a wide range of disciplines –psychology, medicine, public health, bio-engineering and communication science – have completed a four-year research project into eating behaviour in toddlers, older children and adolescents.

While health promotion campaigns often successfully educate children, parents and schools about healthy eating options, very few lead to a real change in behaviours or weight, according to the Reward project.

Rising childhood obesity has been described by the World Health Organization as one of the most serious public health challenges of the 21st century, but it says the problem is largely preventable. The number of overweight Belgian youngsters is, at one in six, relatively low compared with other European countries.

Current methods to combat the issue treat everyone the same while neglecting individual differences and environmental factors, such as easy access to tempting but unhealthy food, according to Reward’s senior researcher and project manager, Leentje Vervoort of Ghent University (UGent).

“Most campaigns rely on just one behaviour change strategy – usually raising awareness – while a combination of more strategies is more likely to succeed,” she says. “This means rewarding desirable behaviour, setting a good example and monitoring habits.” 

Positive incentives

The team, from UGent and the University of Leuven, focused on examining the role of rewards and “reward sensitivity” in children’s eating behaviour. “Reward sensitivity is a personality trait, related to activity in the dopamine pathways of the brain,” explains Vervoort. “It refers to an individual’s ability to experience pleasure or reward when they are exposed to stimuli like sex, music and palatable foods.”

It continuously monitors the environment for signals of reward, she continues, “responds to positive incentives in the environment and activates behaviour to obtain specific rewards. People differ in the activity levels of these dopamine pathways, resulting in different reactions”.

We should make healthy choices more readily available by making them more easily accessible and cheaper

- Leentje Vervoort

Traditional health promotion also tends to overlook the effects that our “obesogenic” environment has on eating behaviour, she adds. This refers to often urban environments that encourage people to eat unhealthily by having an abundance of outlets selling cheap, high-calorie foods. In some areas, an emphasis on driving over walking worsens the problem.

“We should make healthy choices more readily available by making them more easily accessible and cheaper,” says Vervoort, “while ensuring that the unhealthy options are more difficult to obtain. They could be made more expensive, for example, or put on the bottom shelf in the supermarket.”

The Reward project, funded by the Flemish government’s agency for Innovation & Entrepreneurship (IWT), presented its results at a two-day event in Brussels last week. It will lead to specific policy recommendations by various partners, including policymakers, educational institutions, food experts, businesses and childcare services.

A range of tools were developed to help with campaigns, such as instruction videos for day-care centres and kindergartens and a cook book with healthy recipes and tips. A further tool, called the Taste Kit, has been designed to help parents encourage pre-school-aged children to enjoy healthy foods.

“This is a crucial period,” says Vervoort. “What is learned during these early years lays the foundations of later behaviour.”

Tackling pickiness

Laura Vandeweghe, a researcher at UGent’s clinical developmental psychology department, said the manual recognises that “pickiness” in toddlers is common, and sets out a plan to combat it. “The Taste Kit offers an enjoyable, non-coercive and scientifically supported method to teach children to like traditionally disliked foods.”

The purpose, she continues, is to make children eat vegetables “without grumbling or complaining, so mealtime can be a healthy and cosy family moment. The scientific theory behind it is that repeated taste exposures lead to familiarisation and eventually liking, then increased consumption.”

The critical aspect, she says, is familiarising children with the taste by bringing the food into contact with taste buds. Parents shouldn’t force children to swallow the food, as this is usually the most difficult part.

Repeated taste exposures lead to familiarisation and eventually liking, then increased consumption

- Researcher Laura Vandeweghe

Rewards of stickers motivate the children, who are offered a small portion of the disliked vegetable 12 times over two weeks. “Parents are asked not to become angry or frustrated if the child doesn’t want to taste. If the child tastes, they immediately get a sticker,” explains Vandeweghe.

Since the study began in 2012, scientists have used a number of research methods, including questionnaires about eating behaviour, parenting methods and feeding practices; working directly with children in laboratory studies; experiments in schools; and focus groups with parents, kindergarten teachers and day-care centre staff.

The project comprised four PhD projects and the work of three post-doctorate researchers. Vervoort: “We can help children and adolescents to make healthy food choices, irrespective of their individual characteristics. But we should use suitable evidence-based techniques.”

Photo: Ingimage