Thursday, September 1, 2011

Are tightly-knit communities best for obesity prevention?

I am re-posting a guest-post that I wrote in June for my friend and colleague, Travis Saunders, on his blog: 'Obesity Panacea'. I was too lazy then to put the whole thing up on my own blog...Alas, I've come back to it as potential thesis material, so have decided to take the two minutes to format it. You can also view the original post here

I am hoping that researchers and the public at large are starting to get past the ‘blame the victim’ perspective of obesity. True, choice and preference obviously have something to do with it, but we as individuals live and interact in complex environments. Behaviours like sedentarism and eating junk food may be natural responses to opportunities and barriers that are structured by the places in which we live, work, play, or go to school.  And not everyone is likely to be equally affected - protected or prone depending on things such as genes, age, sex, socioeconomic status, cultural upbringing, and the like. We need to consider the context in which people live their lives. If not, obesity prevention and treatment efforts are akin to throwing people back into the fire.

Humans, by nature, are social animals, so one such contextual factor that has garnered a lot of attention in the field of place and health is social capital. It refers to networks of social relationships that people have and the associated norms of <warranted> trust and reciprocity (gift giving with the expectation of receiving) (1).  Social capital can work at the individual level, but also through collective or group-level mechanisms (2).  These group-level workings may be most relevant for the development of obesity, since buying and eating food , as well as being physically active, often (but obviously not always) take place in shared spaces, such as neighbourhoods.  

There is already a vast literature demonstrating an association between low collective social capital and adverse health outcomes such as delayed child development, child and adolescent behaviour problems, stress and isolation, violent crime, and increased mortality (3).  A newer body of research is emerging now, suggesting that low collective social capital may be related to obesity and even related diseases such as hypertension (4).      

Social capital in a collective or community context is often referred to as ‘collective efficacy,’ which is used to describe a number of social processes that may affect health (5). In short, it is the social cohesion (connectedness/togetherness) among neighbours (or members of a community) combined with their willingness to intervene on behalf of the common good.

Okay, so how can that translate into obesity?  I’ll try to spare you the jargon as much as I can while still conveying the meaning of these pathways (one of the main criticisms of this area of research is that words and phrases describing concepts, and the meaning of these concepts are not consistently applied). Also, keep in mind that these pathways can interact and overlap.

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 Informal social control
Neighbourhoods that are more cohesive informally enforce social norms (e.g. obeying the law), which may decrease anti-social behaviours such as graffiti, vandalism, illegal dumping, drug-dealing, violence etc (5).  By informally it is meant that residents are willing to intervene when they see someone breaking social ‘rules’.  This can have an impact on the physical aspect of neighbourhoods, making them more or less aesthetic, as well as on the perception of safety (67). Both may influence resident’s decisions to be active outside (or decisions to let their kids be active outside), as well as decisions by certain groups of people and organizations to move into or out of the neighbourhood (8).  For example, a specialized grocery store relocates out of the neighbourhood to a ‘better’ or ‘safer’ location. Neighbourhood residents therefore, no longer have access to this service.  Another example is calling the SPCA to complain about a certain neighbor (me) letting their dog poop on one’s property and not cleaning it up. In my defense, that dog poop was from winter – I had no idea Jax went over there to do his business, and the snow covered it up! As a result of this we bought a retractable leash and no longer let Jax off-leash in the backyard (to his chagrin).   Maybe now our neighbours do not hesitate as much to let their little girl play in the backyard.  
Somewhat related to social control is how much residents feel that they can depend on their neighbours, and how dependable neighbours actually are. In a more cohesive neighbouhood this mutual trust is high (9). Parents may feel better about and consequently let their child play outside more often when they know there are other people around to look out for the well-being of the child.

Collective action
Increasing the social connectivity of a neighbourhood facilitates coordinated action (9).  Highly cohesive neighbourhoods may have more power to influence physical and social changes within the neighbourhood itself, at higher levels of social organization, such as at municipal and regional levels (I blogged about something similar in a recent post).    For example, if neighbourhood members deem that being in a food desert is a problem they may have the collective might to bring about policies that allow farmers markets to locate within the community, thereby improving the accessibility of healthier foods. Another excellent example of this is DIY streets – an initiative to increase pedestrian and cyclist safety, which has also increased (full circle) a sense of community between neighbours on a street in London, England.

Social contagion
“The Chameleon Effect” is a phenomenon that operates at the level of our unconscious – merely perceiving certain behaviours makes us more likely to engage in those behaviours (10).  In a more connected community, when we see/hear about people being active outside, or say ordering from an organic food basket, we may be more likely to engage in those behaviours (11).  And this may lead to those behaviours becoming a social norm, which thus further reinforces those behaviours.  I use the term ‘social contagion’ perhaps loosely, as the spreading of normative and stable healthy behaviours is likely not a fast process.

Richness and density of social ties
In some sense this operates more at the individual level but is relevant to discuss here.  The more connections an individual has within the neighbourhood the more access they have to health relevant resources (12).  Thus, a person who is isolated within the neighbourhood may not know about easily accessible (and perhaps free) services or amenities such as parks, new grocery stores, etc., or be exposed to health promotion initiatives that are local in scope.  Having rich social interactions on a daily basis may also increase well-being and reduce stress. Individuals prone to isolation (like seniors) may benefit from living in a community with high social interaction – neighbours may periodically check in on and provide support, and a recent study has found that seniors living in areas with high social cohesion are less likely to die from stroke (13)      

Again, this functions more at the individual level but can result, at least in some part, from a lack of collective efficacy at the community level.  More physical and social neighbourhood disorder may illicit psychological distress <either warranted or unwarranted> (6).  Chronic stress has been shown to have direct effects on metabolism and has been linked to obesity (14, 15).  Eating may also be used as a coping strategy (1516) – I do this to self-medicate before a big presentation.

A few thoughts...
There are certainly some caveats in social capital research, particularly at the group-level (I won’t go into them all but you can read about them in a series of articles published by the International Journal of Epidemiology, called the Social Capital Debate).  The literature posits an influence of community social capital on physical activity, healthy eating, and obesity, but it may itself be influenced either by the behaviours themselves (e.g. more people meet outside during a jog), the built environment (e.g. interesting and safe places to walk to), or broader factors such as policies and global social norms.  And certainly, the fact that most of this research has been cross-sectional does not help any to untangle the mess. Social capital can also be a bad thing, such as gangs or perpetuating unhealthy behaviours.

So, if we increase community social capital, will that decrease obesity? And how do we increase community social capital? Good questions, I don’t think we have satisfactory answers yet, unfortunately. A discussion for another day perhaps…


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Szreter, S. (2004). Health by association? Social capital, social theory, and the political economy of public health International Journal of Epidemiology, 33 (4), 650-667 DOI: 10.1093/ije/dyh013