11/15/2014 04:09 pm ET Updated Dec 06, 2017

The Power of Sociogenomics on Health: You Are What Your Friends Eat

The holiday season, more than any other time of year, brings up so much discussion around food and community. This is a time when being fully aware of our food choices is essential, since this is the time of year when we might be apt to stray from making healthy food choices, struggle with money concerns, and face family dynamics head-on. Often, the sum of these happenings has the possibility to shake our foundation, bringing up feelings of instability and insecurity. Although there is something very personal about this time of year -- reflecting on the months passed and all the important moments that will shape the year to come -- this is an especially tender time for family, friends, and community. As we prepare to engage in regular social gatherings for the holidays, it is naturally appropriate to consider the extent to which our relationships can influence the choices we make and their cascading impact into our health.

The success of nutrition science in the future will depend largely on its ability to encompass nutrigenomics, and to embrace the complexity of the individual's dietary needs based on age, gender, location, experiences, genomics, epigenetics, environment, including one's social networks (1). In fact, the science of how influential social networks can be for our health is gaining momentum. Perhaps the movement in this direction started in 2007, when Barabási published the first scientific publication featuring the term "network medicine." In this paper, he stated: "The growing interest in interconnectedness has brought into focus an often ignored issue: networks pervade all aspects of human health" (2). He went on to comment that network-based thinking allows for more expansive approaches to disease, encompassing environment, society, and human interactions (3). The model of the human body as a series of linearly-constructed pathways has been replaced with a vision of an organic, interconnected web of influences. 2014-11-14-shutterstock_999014.jpg

Based on animal social behavior, especially in studies with ants and bees, the principles of sociogenomics, or how socializing systems can integrate into genomics and molecular biology, (4) are becoming more defined. For both animals and humans, organizing societies, and interactions therein, provide direction into the sustainability and success of a community (5). Researchers and renowned scientists, Nicholas Christakis, MD, PhD, MPH, and James Fowler, PhD, present compelling evidence in their book, Connected, (6) on the expansiveness of the ripple-effect connection to others and health benefits and consequences. It is within their study of the whole group structure that it may be more easily understood how social constructs shift the global organism.

Groups of interconnected people can naturally exhibit complicated, shared behaviors. Health decisions are typically based on the norms of social groups, regardless of the implications (7). For example, studies indicate that social networks can determine the quantity and quality of what an individual eats (8, 9) while living arrangements, frequency of social contact, and relationship status have all been shown to impact health behavior (10, 11).

The sociology of health and medicine is formed through interdependent webs of support, influence, and engagement (12). This linkage is evident in interactions with healthcare professionals, but is also crucial within intimate relationships. Early research in the 1970s by pioneers, Cassel, Cobb, and Berkman, showed that social networks impact mortality (13, 14, 15). Interdependence between spouses can contribute to negative health consequences. For example, the "hospitalization of one spouse was found to increase the risk of death of the other" (16). Still, even weak social networks can be influencing (17).

Health behaviors, regardless of whether those behaviors are beneficial or detrimental, are dependent upon relationships. Tobacco use, alcohol consumption, drug use, exercise, and weight gain are all socially transmittable (18, 19, 20). In fact, in addition to the above, Christakis and Fowler collected a vast amount of data from many sources examining the "spread" of food consumption, health screening, happiness, loneliness, depression, sleep, divorce, cooperative behavior, influenza, sexuality and sexual orientation, and tastes in music, books, and movies (21).

Christakis and Fowler's 2010 smoking study showed that "groups of inter-connected people quit in concert and smokers are increasingly marginalized socially (22). They also documented "how obesity can spread through social networks in a manner reminiscent of an infectious disease or a fad -- a kind of person-to-person contagion of bio-behavior" (23). The same study also found that the likelihood of a person becoming obese was influenced by "whether or not his/her social contacts became obese during the same period" (24).

Similarly, social networks have the capacity for positive influence on individual health behaviors. For example, sharing meals has been used as a therapeutic modality in the treatment of eating disorders among adolescents because, among other things, it creates a sense of belonging (25). Studies have shown that sharing meals benefits elderly populations as well. Out of a group of 130 elderly adults, those who more regularly shared meals with others or ate in a social setting had the best overall health and nutrient intake (26). Those with the lowest nutrient intake maintained a more isolated lifestyle in the community.

Medicine in the 21st century carries within it the dichotomy of connection through the collective community on the greater whole and a collapse into the intricacies and personalization that is required to address the needs of one individual. Based on recent findings, it would seem that the natural progression of where medicine needs to go is into furthering the advancement of the knowledge of the complexity of the individual and population through a model that embraces the influence of social networks.


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