Obesity and related disorders are a growing concern throughout the world. Although there are genetic predispositions to obesity, the number of genes involved is very large. Furthermore the rapidly increasing frequency of overweight and obese individuals in many parts of the world cannot be due to increase in frequencies of any of the obesity related genes. Therefore more attention is focused on gene-environment-behavior interactions contributing to the obesity epidemic. Classically obesity is viewed as a means of energy storage. One of the popular classical concepts has been that of metabolic thriftiness. The thrifty gene is said to confer the ability to store fat at times of food abundance and allow reutilization during food crunch.
However, Manasee Mankar and his associate at Department of Microbiology, Abasaheb Garware College, Pune, India, in a recent research has highlighted many neuro-behavioral and social aspects of obesity, with a suggestion that obesity, especially abdominal obesity, may have evolved as a social signal.
They tested whether body proportions and abdominal obesity in particular, are perceived as signals revealing personality traits. Faceless drawings of three male body forms namely lean, muscular and feminine, each with and without abdominal obesity were shown in a randomized order to a group of 222 respondents. A list of 30 different adjectives or short descriptions of personality traits was given to each respondent and they were asked to allocate the most appropriate figure to each of them independently.
The traits included those directly related to physique, those related to nature, attitude and moral character and also those related to social status. For 29 out of the 30 adjectives people consistently attributed specific body forms. Based on common choices, the 30 traits could be clustered into distinct ‘personalities’ which were strongly associated with particular body forms.
A centrally obese figure was perceived as “lethargic, greedy, political, money-minded, selfish and rich”. The results show that body proportions are perceived to reflect personality traits and this raises the possibility that in addition to energy storage, social selection may have played some role in shaping the biology of obesity