Individuals often make resolutions in January to maintain healthy lifestyle regimes — for example to eat better or exercise more often — then fail to keep them.

Behavioural scientists frequently interpret such behaviour as evidence of a conflict between two ‘selves’ of a person — a Planner (in charge of self-control) and a Doer (who responds spontaneously to the temptations of the moment).

A team of researchers from the Universities of East Anglia (UEA), Warwick, Cardiff and Lancaster in the UK and Passau in Germany investigated how far people identify with their Planners and their Doers.

They found that while participants differed in the relative importance they attached to spontaneity and self-control, overall, attitudes in favour of spontaneity were almost as common as attitudes in favour of self-control.

Public policies designed to ‘nudge’ people towards healthy lifestyles are often justified on the grounds that people think of their Planners as their true selves and disown the actions of their Doers.

However, in their study published today in the journal Behavioural Public Policy, the authors argue this justification overlooks the possibility that people value spontaneity as well as self-control, and approve of their own flexible attitudes to resolutions.

Robert Sugden, a professor of economics at UEA, said: “Our key message is not about whether nudges towards healthy lifestyles are good for people’s long-term health or happiness. It is about whether such nudges can be justified on the grounds that they help individuals to overcome what they themselves acknowledge as self-control problems.

“If that idea is to be used as a guiding principle for public policy, we need to be assured that individuals want to be helped in this way. Our findings suggest that people often may not want this.”

Co-author Andrea Isoni, a professor of behavioural science at Warwick Business School, said: “We conclude that identifying when and where individuals want to be helped to avoid self-control failures is not as straightforward as many behavioural economists seem to think.

“We believe our findings point to the importance of treating desires for spontaneity as equally deserving of attention as desires for self-control, and as suggesting interesting lines of further research.

“One idea it would be useful to investigate is whether some kinds of deviation from long-term goals are viewed as more spontaneity-affirming than others. For example, we found a contrast between our respondents’ spontaneity-favouring attitudes to sugary drinks and restaurant desserts and their self-control-favouring attitudes to exercise. Breaking a health-oriented resolution by ordering a crème brûlée is perhaps a more positive way of expressing spontaneity than not taking one’s daily run on a wet day.”

The experiment, run via an online survey, began by asking each of the 240 participants to recall and write about a particular type of previous episode in their life. For some, this was a memorable meal when they had particularly enjoyed the food; for others, it was an effort they had made that was good for their health and they felt satisfied about.

They were then asked to say how well they recognised themselves in various statements. These included wishes for more self-control (eg, ‘I wish I took more exercise’), regret about lapses of self-control (‘After ordering desserts in restaurants, I often feel regret’), and approval of self-control as a life strategy (‘In life it’s important to be able to resist temptation’).

An equal number of statements expressed wishes for less self-control (eg, ‘I wish there was less social pressure to take exercise’), regret about exercising self-control (‘After ordering a healthy dish, I often wish I’d chosen something tastier’), and approval of spontaneity (‘Having occasional treats is an important source of happiness for me, even if they are bad for my health’).

Overall, respondents recognised themselves almost as often in statements favouring spontaneity as in statements favouring self-control. In responding to statements about what was important in life, most participants maintained both that it was important to make long-term plans and stick to them and that there was no harm in occasionally taking small enjoyments rather than sticking to those plans. Surprisingly, attitudes were not significantly affected by the type of episode respondents had recalled.

The research was supported by funding from the Economic and Social Research Council and the European Research Council under the European Union’s Horizon 2020 research and innovation programme.