Ouders weten dat het lastig is om kinderen te motiveren om meer groenten en fruit te eten. Recent onderzoek van Brian Wansink en collega's laat zien dat het geven van 'catchy' namen aan groenten, zoals Power Brocolli, kinderen meer laat eten.
Vanochtend werd ik geinterviewd door Humberto Tan van BNR Nieuwsradio over het gebruik van marketingtechnieken om kinderen aan de groente te krijgen.
Luister hier het fragment:
Nudging consumers towards healthier food choices is still a hot topic. Drawing on psychology and behavioural economics, nudges are simple intervention strategies to move consumers towards healthier choices. This is done without banning foods products or telling consumers what to eat or avoid.
There are quite a few examples of successful nudges that help consumers in making better food choices. For instance, if consumers were asked to downsize their side dish, they ended up eating less in the study of Schwartz and colleagues. Still, there is a lot of debate about the usefulness of nudging. Consumers need more than a nudge, is the argument put forward by Lucy Handley. Lord Krebs recently argued in the Guardian that nudging alone will not convince people to do important things like lose weight. They both might be right, but at the same time I think it very useful to collect empirical evidence on the effectiveness of nudging.
Last Summer, we carried out a nudge study among 113 primary school children (10-12 years old) to encourage them to go for a healthier snack. We were inspired by the proven marketing tactic to offer a free gift with purchase (think of McDonald's Happy Meal). Typically, children are confronted with these free gifts on energy dense snacks. But would it be effective to use this classic marketing tactic to encourage children to switch to something healthier? That was the key question in our virtual supermarket study on which Charlotte Petri graduated last August.
We asked children to do some groceries in the virtual supermarket and select their own snack and drink near the checkout counter. This simulated supermarket of Wageningen University looks like a real supermarket with various shelves
which display three-dimensional images of a wide range of products. The children could walk through the aisles of the store and put products in their
virtual shopping cart.
Participant chooses a snack in the virtual supermarket
Participants did not see the same snack shelf, however. One third of all participants were confronted with a shelf poster that promised them a free gift (a tattoo) when they would buy a product with a star. These 'star products' were all healthier options as indicated by the Dutch Nutrition Centre. Another group were similarly promised the same gift, but now the star was attached to relative unhealthy snacks. The third group was the control group who did not get to see any promise of a free gift.
Snack shelf with poster promising free tatto gift with healthy 'Star' purchase
Most children were very enthusiastic about 'shopping' in the virtual supermarket ('Where can I download this game?'). Less than half of all children selected a healthy snack and drink. They were, however, not influenced by the promised free gift, regardless of the type of product to which the star was attached. It could be that the gift was not attractive enough, although a pre-test indicated differently. Another explanation is that children might have been too focused on the shopping task. In other words, they were too 'busy 'walking' through the shop, impressed by the new experience.
About one fifth of all participants was overweight. This percentage is similar to the percentage Dutch children who is overweight. Although overweight children more often tended to go for unhealthy snacks, they were not more sensitive to the free gift than normal-weight children. Children chose snacks based on familiarity and preference. Health was less important in their choice.
Overall, although the nudge was not effective in its present form, we learned a lot about the possibilities of the virtual supermarket for choice experiments with children. Have a look at the video, in which a participant walks through the supermarket and makes her snack choice.
'Also happy with this environment?' is the question posed by the Dutch Nutrition Center in their new campaign. The video of this campaign is definitely worth watching.
Many children have poor eating habits which may lead to overweight and obesity. Children are constantly bombarded with unhealthy, high-caloric snacks and meals. As a result, children nowadays live in a so-called 'toxic food environment', a term invented by obesity researcher Kelly Brownell.
Successful obesity awareness campaigns require careful consideration of the target group and a key relevant message. On the one hand, they need to make parents aware of the seriousness of the problem. On the other hand, they need to provide useful information and not stigmatize or shame overweight children. This is not simple, as shown by a failed and controversial US childhood obesity campaign.
I particularly like the final scene of the video in which Lukas refuses the healthy meal cooked by his parents. It is a very familiar scene for many parents, including myself. Have a look yourself!
A key reason we are getting overweight is because we eat too large portion sizes of food. But is this overeating giving us more satisfaction? Could eating smaller portions be similarly effective in decreasing food cravings or feelings of hunger as larger portions? That was the key question in the study that I conducted with Mitsuru Shimizu and Brian Wansink while visiting the Food and Brand lab. The paper is now published in Food Quality and Preference (see also full-text paper).
We presented 104 participants with either a small portion of three commonly craved snacks - chocolate, potato chips and apple pie - or substantial larger portions of the same snacks. For example, the small portion of chocolate was 10 grams, while the large portion was 100 grams. Feelings of hunger and craving were assessed just before participants started with the taste test, immediately after the taste test and about 15 minutes later. Secretly, we also measured how much participants ate.
Results show that although providing larger food portions increased snack calorie intake by 77% (103 calories), after 15 minutes, they do not reduce hunger or cravings any more than smaller portions. In other words, after 15 minutes, when all food was out of sight, everyone was equally happy.
A typical snack in the US contains about 264 calories (see Piernas and Popkin, 2010). This amount closely resembles the total calories consumed in the large portion size condition in our study (about 237 calories). Nevertheless, although participants in the small portion size condition ate considerably less (about 134 calories, which is about 51% of what people typically snack), they were equally tempted by the snacks. This shows that whereas large portions tend to increase food intake, smaller portions may make you equally satisfied.
Going for the large portion size of their favourite food
How to stop eating when you are craving a food? One way is to make sure that there is less food in front of you in the first place. That is not simple. Large food portions are common in supermarkets, restaurants and even at home. Portion sizes of many foods have increased during the last decades and we are getting used to it. For example, snack foods and beverages are offered in increasingly large packages. Although many consumers find 'value for money' important, it would be better to stop the emphasis of getting more food for you money. Smaller portion sizes can help you limit the amount of food you eat.
