What factors govern the daily decisions we make about food, exercise, and other health behaviours? As my colleague Megan noted in a recent post on Behavioural Economics on her blog Verdant Nation, “our choices arise from opportunities or barriers that are structured in large part by the places in which we live, work, play, or go to school“. In addition to these environmental influences on choice, what other factors enhance or impair our decision making?
An important underlying factor that affects all the conscious choices we make is that our mental resources available for decision making are limited, according to research by Baumeister and colleagues (1,2). Executive decisions that require reasoning, conscious thought, initiate behaviour or over-ride instinctive responses draw on and can deplete this “energy”. For example, resisting the temptation to buy a new pair of shoes may later lead to a reduced ability to say no to a second piece of cake for dessert. In a series of experiments, the researchers tested several conditions to determine their impact on subsequent decision making (1):
- exercising restraint (such as resisting temptation to eat chocolate chip cookies)
- making a deliberate and responsible choice (versus not being given a choice)
- suppressing emotions
- making an active choice (versus a default option which occurs passively)
All conditions were found to support the researchers’ hypothesis, that an initial act of volition deplete resources available for subsequent decision making. Subsequent work has confirmed this finding, also supporting the additional notion that making an active choice impairs future decision making to a greater extent than simply deliberating over options or following choices made by someone else (2). Schwartz and colleagues also argue that the stress associated with making a choice lingers even after the choice is made. This contributes not only to dissatisfaction with the decision itself, but the resulting experience from that decision as well (3). Again, this can impair future decision making.
Although our society values freedom of choice, too much choice also impairs decision making (4). Iyengar and Lepper investigated how increasing the number of options subjects could choose from affected the outcome of the decisions. In one experiment, shoppers at a supermarket were presented with a tasting sample of either 6 or 24 different flavours of jam. Consumers provided only 6 choices were more likely to purchase a jar of jam compared to consumers who were presented with 24. Similarly, students given the opportunity to write a 2-page paper for extra credit were more likely to complete the assignment if only given 6 choices of topic compared to 30. Perhaps more surprisingly, a limited number of choices was also linked to better performance on the essay! (4)
What do these observations mean for individuals trying to make healthy choices? For example, they help explain why an individual may “run out of will-power” when eating out for an evening meal, and why it is hard to choose something new (and perhaps healthier) when faced with an overwhelming amount of food choices in the grocery store. How can we take advantage of this information to provide optimal support for making healthy decisions? I’ll explore some ideas in an upcoming post.
1. Baumeister, R., Bratslavsky, E., Muraven, M., & Tice, D. (1998). Ego depletion: Is the active self a limited resource? Journal of Personality and Social Psychology, 74 (5), 1252-1265 DOI: 10.1037//0022-35184.108.40.2062
2. Vohs KD, Baumeister RF, Schmeichel BJ, et al. Making choices impairs subsequent self-control: a limited-resource account of decision making, self-regulation, and active initiative. Journal of Personality and Social Psychology. 2008;94(5):883-98. Available at: http://www.ncbi.nlm.nih.gov/pubmed/18444745
3. Keys, D. J., & Schwartz, B. (2007). “Leaky” Rationality: How Research on Behavioral Decision Making Challenges Normative Standards of Rationality. Perspectives on Psychological Science, 2(2), 162-180. doi:10.1111/j.1745-6916.2007.00035.x
4. Iyengar, S. S., & Lepper, M. R. (2000). When choice is demotivating: Can one desire too much of a good thing? Journal of Personality and Social Psychology, 79(6), 995-1006. doi:10.1037/0022-35220.127.116.115