So-called ‘nudging’ – encouragement to adopt healthier behaviours – may be ineffective and wasteful, caution experts on bmj.com today. They argue that the approach, while fashionable, is not evidence-based and may be no better than other strategies for improving public health.
Whereas nannying uses incentives or even bans to try to positively influence people’s lifestyle choices, nudging is supposed to achieve this by altering environments to prompt change. It is widely used by industry to promote consumption of alcohol and junk foods.
The authors of this analysis argue that there is no strong, scientific evidence for the effectiveness of nudging in encouraging healthier behaviour across the population. Theresa Marteau, director of the behaviour and health research unit at Cambridge University, and her colleagues say that the idea of nudging has proved popular because it appears simple and cheap, and has been shown to work in certain cases. Demarcating a special section of supermarket trolleys as being specifically for fruit and vegetables, for example, led people to double the amount that they bought. And school children bought 70% more fruit for lunch when it was placed by the till in the school canteen.
But the authors point out that, “at present, the evidence to support the view that nudging alone can improve population health is weak.” They add that, worse still, nudging could even increase harms as well as benefits, if it leads to less emphasis being placed on other, potentially more effective interventions.
They call for more research to find practical, cost-effective examples of where nudging can work. They conclude that: “Without regulation to limit the potent effects of unhealthy nudges in existing environments shaped largely by industry, nudging towards healthier behaviour may struggle to make much impression on the scale and distribution of behaviour change needed to improve population health to the level required to reduce the burden of chronic disease in the UK and beyond.”
In their accompanying editorial, Chris Bonell and colleagues at the London School of Hygiene and Tropical Medicine say that the definition of nudging hasn’t even been clarified, and argue that it adds nothing to existing approaches and risks wasting resources. They caution that “little progress will be made if public health policy is made largely on the basis of ideology and ill-defined notions that fail to deal with the range of barriers to healthy living.”