In chapter 2 of my forthcoming trade book The Consuming Instinct: What Juicy Burgers, Ferraris, Pornography, and Gift Giving Reveal About Human Nature
(Prometheus Books, 2011), I tackle consumer choices that map onto our survival instinct. For those interested, I also addressed this issue in my 2007 book The Evolutionary Bases of Consumption
(chapter 3). As you might imagine, food constitutes the most obvious survival-related consumer choice.
One of the relevant studies that I cite in my two books constitutes the topic of today's post. It is an "oldie but goodie" study published in 1969 that explored the link between situational hunger and grocery purchases. Richard E. Nisbett and David E. Kanouse tracked the grocery bills of "normal weight" individuals (n = 134) as well as their overweight counterparts (n = 149), and linked these to shoppers' levels of food deprivation (i.e., a proxy measure of situational hunger). I would have thought that both groups would display a positive relationship between situational hunger and grocery bill (an instantiation of the deficit hypothesis for food hoarding), with the relationship being stronger for the overweight consumers. This is not what was found, at least not for the overweight shoppers.
Whereas for the non-obese consumers, the expected positive relationship was confirmed, the overweight consumers spent less money the more food deprived they were. The authors argued that for overweight people, appetitive cues are less driven by internal states, and as such their situational hunger did not cause them to augment the amount of food purchases (although other external cues might). This strikes me as a rather surprising finding, although I suppose that one of the reasons for being overweight is the fact that one does not respond as "appropriately" to internal signals of satiety or hunger.
The bottom line: The findings for the "normal weight" consumers struck me as being in line with theoretical predictions whereas those of the obese consumers were certainly surprising (for another study demonstrating the expected positive relationship between food purchases and situational hunger, see here; for a replication of the "surprising" effect regarding the differential nature of this relationship for obese and non-obese people, see here).
Those of you interested in food hoarding might wish to read my earlier post on behaviors at a Chinese buffet (see here).
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