Health Knowledge or Value of Health: Understanding Socieconomic Disparities in Unhealthy Consumption

"How can we induce people to look after their health?" was recently chosen as the most pressing question in the social sciences (Giles, 2011). Given the strong disparities in health behavior across socioeconomic groups (e.g., Cutler and Lleras-Muney 2010), the biggest challenge will be to make the poor and lower educated behave healthily. Yet, in a recent review Cutler et al. (2011) note that the underlying reasons for differences in health behavior across socioeconomic groups remain largely unclear.

In this paper we aim to understand differences in unhealthy food choices across socioeconomic groups. We do so by using an economic theory of unhealthy consumption to help designing a Discrete Choice Experiment (DCE), in which individuals are offered two hypothetical food options between which they have to choose. The DCE is implemented in existing Dutch survey data.

In the DCE, each choice set will consist of two alternatives, each with 4 attributes. The selection of attributes is directed by the theoretical model developed by Galama and Van Kippersluis (2010), and coincides with the seminal Food Choice Questionnaire developed by Steptoe et al. (1995). The first attribute is “sensory appeal” which will capture preferences for unhealthy consumption. The second attribute is “monetary price”, and the third attribute is “own time input” measuring the opportunity cost of time. The final attribute is “health consequences” which can be thought of as an index of unhealthiness for the alternative.

The DCE enables us to estimate which attributes of food choice are most important, and how this differs across socioeconomic groups. The theory predicts that differences in the so-called “health cost” play a large role. The health cost is the ‘value’ people attach to health, multiplied by the reduction in health due to unhealthy choice of food. This reduction in health affects food choice to the extent that the individual “knows” about the health consequences of her choice. Our second aim is therefore to investigate the relative roles of (i) health knowledge and (ii) value of health in explaining socioeconomic differences in food choice.

The described DCE is only partially suitable to investigate this, as it equalizes health knowledge across all respondents by providing direct information on the health consequences. As a result, in this scenario, all differences observed in the importance of health consequences must be due to differences in valuation of health. To be able to assess the role of health knowledge, we set up two alternative scenarios. In both alternative scenarios, we exclude health consequences as a single attribute but provide the respondents with a number of health related attributes of the alternative, i.e. calories, sodium, saturated fat, and fiber. Difference between the two alternative scenarios is that in one scenario we include dietary guidelines about what is healthy and what is not, and in the other scenario we exclude this information.

The results of the study will help in understanding socioeconomic differences in unhealthy food consumption – do the poor eat unhealthier because they know less or because they care less?