An increasingly common phenomenon in modern work and school settings is individuals taking on too many tasks and spending effort without commensurate rewards. Such an imbalance of efforts and rewards leads to myriad negative consequences, such as burnout, anxiety and disease. Here, we develop a model to explain how such effort–reward imbalances can come about as a result of biased social learning dynamics. Our model is based on a phenomenon that on some US college campuses is called ‘the floating duck syndrome’. This phrase refers to the social pressure on individuals to advertise their successes but hide the struggles and the effort put in to achieve them. We show that a bias against revealing the true effort results in social learning dynamics that lead others to underestimate the difficulty of the world. This in turn leads individuals to both invest too much total effort and spread this effort over too many activities, reducing the success rate from each activity and creating effort–reward imbalances. We also consider potential ways to counteract the floating duck effect: we find that solutions other than addressing the root cause, biased observation of effort, are unlikely to work.

The aims of this study were to investigate the associations between work stress defined by the effort–reward imbalance (ERI) model and diet quality and to examine the potential role of over-commitment (OC) personality in ERI–diet relationships. A cross-sectional study was conducted in random population samples of 6340 men and 5792 women (age 45–69 years) from the Czech Republic, Russia and Poland. Dietary data were collected using FFQ. The healthy diet indicator (HDI) was constructed using eight nutrient/food intakes (HDI components) to reflect the adherence to WHO dietary guideline. The extent of imbalance between effort and reward was measured by the effort:reward (ER) ratio; the effort score was the numerator and the reward score was multiplied by a factor adjusting for unequal number of items in the denominator. Logistic regression and linear regression were used to assess the associations between exposures (ER ratio and OC) and outcomes (HDI components and HDI) after adjustment for confounders and mediators. The results showed that high ER ratio and high OC were significantly associated with unhealthy diet quality. For a 1-sd increase in the ER ratio, HDI was reduced by 0·030 and 0·033 sd in men and women, and for a 1-sd increase in OC, HDI was decreased by 0·036 and 0·032 sd in men and women, respectively. The modifying role of OC in ERI–diet relationships was non-significant. To improve diet quality at workplace, a multiple-level approach combining organisational intervention for work stress and individual intervention for vulnerable personality is recommended.