London School of Hygiene & Tropical Medicine

The Government should not rush to embrace the idea of 'nudging' people to adopt healthier behaviour, as there is no evidence to suggest it is an effective strategy, according to an editorial published in the week's British Medical Journal.

A team based at the London School of Hygiene & Tropical Medicine criticises the emphasis placed on 'nudging' in the recent White Paper on public health, 'Healthy Lives, Healthy People', claiming that it is a confused and ill-defined concept which many not offer anything new in terms of improving people's health behaviour.

The concept of 'nudging' was first described in Nudge: Improving Decisions about Health, Wealth and Happiness, a book by the US academics Richard Thaler and Cass Sunstein. They argue that most decisions people make are unconscious or irrational and governments should try to influence people's behaviour to make their lives healthier as long as this doesn't involve coercion or significant financial pressures. 'Nudges' may involve actions such as increasing the prominence of healthy food in canteens, requiring people to opt out of rather than into organ donor schemes or providing small incentives for people to act more healthily. They are, in effect, anything other than giving basic factual information, introducing bans or bringing heavy financial pressures to bear.

But the LSHTM team argues that we shouldn't rush into doing lots of new research on nudges unless we're confident that it offers something new. But this is far from clear because like nudges most existing public health isn't coercive (and where it is, like the smoking ban, this is usually to prevent harm to third parties) and goes beyond the facts to influence how choices are presented (for example using techniques like social marketing, motivational interviewing and peer education).

They point out that many of the examples in Thaler and Sunstein's book don't fit with their own definition - for example a programme paying a 'dollar a day' to teenage mothers contingent on their having no further pregnancies would exert major pressure on young women in poverty, contradicting their definition of nudges as not exerting such pressures.

Lead author Chris Bonell comments: 'The notion of nudging adds nothing to existing approaches. Public health policies should be based on the best available evidence, but the Government has shown a worrying tendency to undermine the collection of such evidence, for example by stopping the National Institute for Health and Clinical Excellence from undertaking appraisals of several strategies to improve public health. 'Nudge' contains some eye-catching ideas, but 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'.

• One nudge forward, two steps back. Chris Bonell, Martin McKee, Adam Fletcher, Paul Wilkinson, Andy Haines. doi: 10.1136/bmj.d228