Promoting healthy eating with nudging.

The present study aims to evaluate an intervention based on nudge theory to promote healthy eating in football canteens. Nudges are small, low-cost alterations in the environment that promote one type of behaviour over the other without affecting freedom of choice. The intervention will be implemented in 3 phases in two football canteens in the Netherlands. The first phase consists of adding 8 new products to the canteens that can be considered a healthy alternative to current products in the assortment. The second phase consists of adding nudge techniques to promote the sale of these products and correcting when there are deviations from the protocol in the experimental canteen, while the control canteen will still only have the addition of the 8 new products. In the third phase, both canteens will sell the new products while promoting them with the use of nudge techniques. In this phase deviations from the protocol will not be corrected. Our interest lies in the (long-term) effect of the nudges on sales records and in the formation of habitual healthy choosing behaviour in football canteens. These, and the reach of the intervention, will ultimately informs us about the possible public health impact of an intervention based on nudge theory.

1) Product sales of specific products will increase during phases in which these products are nudged.

2) The effect of nudges on product sales (hypothesis 1) persists in the long-term, without active control of the experimenter.

3) Participants in the experimental canteen will form stronger habits for buying the products than participants in the control canteen.

4) Nudges in the football canteens reach a significant amount of people.

Primary outcomes (control canteen):

Sales records: 0 weeks, 4 weeks, 13 weeks, 38 weeks

Habit strength (SRBAI): 4 weeks, 13 weeks, 38 weeks

Reach: 29 weeks



Primary outcomes (experimental canteen):

Sales records: 0 weeks, 6 weeks, 15 weeks, 38 weeks

Habit strength (SRBAI): 6 weeks, 15 weeks, 38 weeks

Reach: 29 weeks



Secondary outcomes (control canteen):

Habit strength (SRBAI): 8 weeks, 29 weeks

Net profit margin: 0 weeks, 4 weeks, 13 weeks, 38 weeks

Self-regulation of eating behaviour (SRBEQ): 4 weeks, 8 weeks, 13 weeks, 29 weeks, 38 weeks

Self-reported behaviour in the football canteen: 4 weeks, 8 weeks, 13 weeks, 29 weeks, 38 weeks

Healthy eating goals: 4 weeks

Adherence: 4 weeks, 13 weeks, 29 weeks, 38 weeks

Ease or difficulty with adherence ( interviews with canteen personnel): 38 weeks

Acceptability of intervention (interviews with canteen personnel and players): 38 weeks

Perceived effectiveness (interviews with canteen personnel): 38 weeks



Secondary outcomes (experimental canteen):

Habit strength (SRBAI): 10 weeks, 29 weeks

Reach: 29 weeks

Net profit margin: 0 weeks, 6 weeks, 15 weeks, 38 weeks

Self-regulation of eating behaviour (SRBEQ): 6 weeks, 10 weeks, 15 weeks, 29 weeks, 38 weeks

Self-reported behaviour in the football canteen: 6 weeks, 10 weeks, 15 weeks, 29 weeks, 38 weeks

Healthy eating goals: 6 weeks

Adherence: 6 weeks, 8 weeks, 11 weeks, 15 weeks, 29 weeks, 38 weeks

Ease or difficulty with adherence (interviews with canteen personnel): 15 weeks, 38 weeks

Acceptability of intervention (interviews with canteen personnel and players): 15 weeks, 38 weeks

Perceived effectiveness (interviews with canteen personnel): 15 weeks, 38 weeks

In this study an intervention based on nudge theory will be evaluated with the aim to increase healthy food and drink consumption in football canteens. The intervention consists of the expansion of football canteens’ assortment with 8 new products. These products can be considered a healthy alternative to existing products. The products are nudged in a variety of ways (e.g. made more visible and accessible). Both the experimental and control group will receive the intervention in its whole, but will differ with regard to the duration of the phases in which the separate elements of the intervention are being implemented. The experimental canteen will expand its assortment with the new products for 4 weeks, after which 9 weeks will follow in which these products are nudged. During these weeks, deviations from the protocol are corrected. After the holidays in which canteens are not visited, 17 weeks will follow in which the intervention is active, but without any correction. The control canteen will expand its assortment for 13 weeks and after the holidays will then also implement nudges for 17 weeks. Here, just as is the case in the experimental canteen, deviations from the protocol will not be corrected.