Today the news is full of stories of the “obesity epidemic.” The levels of obesity, especially childhood obesity, have grown significantly over the past few decades. A biological explanation, based on genetics and hormones, is not sufficient to explain the rising number of obese people on the planet.  Two sociocultural factors that may be involved in the rise of obesity are the change to a more sedentary lifestyle and a change in the types of foods we eat.  

As more people have left the rural communities and moved to cities, we also see people living a more sedentary lifestyle.  More and more work is done on computers, so people spend a good part of their day sitting.  In addition, the use of cars and public transportation means that people walk less and less.  Psychologists believe that this cultural change has led to the growth of obesity rates. Prentice & Jebb found a positive correlation between an increase in obesity in a society and car ownership and television viewing. The research was based on large amounts of data, which makes the data more reliable.  However, this study is correlational, so it cannot establish a cause and effect relationship.  It could very well be that because people have become more overweight or obese, they choose to watch more television or not walk as much.  This bidirectional ambiguity is common in sociocultural research where it is difficult to set up meaningful experiments.  

However, a sedentary lifestyle alone cannot be held responsible for the obesity epidemic.   A cultural shift in diet also has an effect.  Joseph et al looked at the rising trend of eating fast food in India on the rise of obesity.  The study looked at three private schools in Southern India.  The study was based on semi-structured interviews and a questionnaire.  In their study, 15% of the boys were overweight or obese. The researchers found that increased consumption of fast food was correlated with being overweight or obese. However, once again, the study is correlational and does not clearly indicate a cause and effect relationship.  In addition, the study is not prospective only looking at current weight and attempting to link it to fast food. It does not account for the children's birth weight, parental eating habits or regular exercise patterns.  Although these questions were asked in the questionnaire, responses are imprecise and may be open to memory distortion or optimism bias.

In several studies, it had been found that in lower-income countries, people with higher socioeconomic status were more likely to be obese. On the other hand, in high-income countries, those with higher SES were less likely to be obese.  This can be explained by the type of food available in a society.  In low-income countries, the low SES families do not have access to adequate calories, whereas in high-income countries, low SES eat poorer quality food – and are often less educated or unable to afford healthier food options.

Sociocultural arguments have the strength that they explain change over time, which is something that biological research struggles to do. They also tend to look at larger samples, making it more possible to generalize the findings.  However, sociocultural arguments cannot separate themselves from biological arguments.  A major component of low SES in a wealthy country is stress.  We know that stress causes the body to store fat. This was seen in the Dutch Hunger Winter study in which it was found that when women were pregnant during the Second World War and suffering from malnutrition, their offspring would then struggle with obesity. This is because their genes were expressed to store fat, and this was passed on to their children.  So, although the sociocultural arguments contribute to a richer understanding of obesity, they cannot be isolated from biological arguments.  The Dutch Hunger Winter study is important because it demonstrates how both environmental and biological factors play a role in obesity.  The study was longitudinal and was naturalistic, giving it a high level of reliability.  However, as the situation was unique, it makes it difficult to replicate the findings and thus generalize the findings.

Finally, sociocultural arguments are problematic because it is not possible to isolate variables. When discussing a “sedentary lifestyle,” this is difficult to accurately measure.  It is also difficult to control for other factors – genetics, metabolism, social support, socioeconomic status and education.  Although several studies attempt to match these factors when drawing conclusions, it is difficult to see how these factors interact.  This is why today psychologists prefer the biopsychosocial model of obesity which argues that no one factor would be responsible for obesity, but the interaction of several risk factors is necessary in order to develop the problem.