title: BMI is not related to altruism, fairness, trust or reciprocity: Experimental evidence from the field and the lab.
abstract: Over the past few decades obesity has become one of the largest public policy concerns among the adult population in the developed world. Obesity and overweight are hypothesized to affect individuals' sociability through a number of channels, including discrimination and low self-esteem. However, whether these effects translate into differential behavioural patterns in social interactions remains unknown. In two large-scale economic experiments, we explore the relationship between Body Mass Index (BMI) and social behaviour, using three paradigmatic economic games: the dictator, ultimatum, and trust games. Our first experiment employs a representative sample of a Spanish city's population (N=753), while the second employs a sample of university students from the same city (N=618). Measures of altruism, fairness/equality, trust and reciprocity are obtained from participants' experimental decisions. Using a variety of regression specifications and control variables, our results suggest that BMI does not exert an effect on any of these social preferences. Some implications of these findings are discussed.
authors.affiliation: Economics Department, Middlesex University Business School, London, UK. Electronic address: economicsbehavioural1@gmail.com.
authors.forename: Pablo
authors.initials: P
authors.lastname: Brañas-Garza
authors.affiliation: Economics Department, Middlesex University Business School, London, UK; Granada Lab of Behavioral Economics (GLoBE), Universidad de Granada, Spain.
authors.forename: Antonio M
authors.initials: AM
authors.lastname: Espín
authors.affiliation: Economics Department, Middlesex University Business School, London, UK.
authors.forename: Balint
authors.initials: B
authors.lastname: Lenkei
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000533:Altruism; D015992:Body Mass Index; D002755:Choice Behavior; D005260:Female; D005717:Games, Experimental; D006801:Humans; D007398:Interpersonal Relations; D008297:Male; D008875:Middle Aged; D018803:Models, Economic; D050177:Overweight / Q000523:psychology*; D012919:Social Behavior; D011795:Surveys and Questionnaires; D035502:Trust
keywords: BMI; Dictator game; Economic experiments; Obesity; Social preferences; Trust game; Ultimatum game