In the United States — the land of opportunity, individual freedom and self-determination — we face a considerable amount of scrutiny from others regarding our personal lifestyle choices. It is perhaps the quintessential American way of life to make our choices while we consider the vast wealth of pleasure and comfort that arises from our capitalist, consumer society. The onus of making the “correct” decision, therefore, has only increased with time, and we must be particularly careful when considering the scientific information that provides insights into our lifestyle decisions. This has never been more true than with the epidemic of obesity in this country. We must take the highest caution when displacing responsibility out the hands of individuals and the extent to which they can make lifestyle choices toward the fatalism of genetic predetermination.
In our attempt to clarify the complex issue of obesity, it is important to recognize the panoply of factors that influence it, including physical activity, environmental elements, dieting and, most controversially, genetics. The growing attention, however, that has been placed on the understanding of genetics and its role in obesity clarifies its own influence as well as that of all the other factors. It has also unfortunately led to opposing conclusions. Somewhat paradoxically, as our understanding of the human genome expands, so too does the convolution surrounding the debate of the culpability of the causes of obesity.
The fundamental dynamic of gene expression in determining obesity is becoming increasingly clearer. Research in this area has identified that there are hundreds of genes that are the genetic underpinning of “common obesity” in contradistinction to the clearer, rarer causes of obesity diseases that are resultant from a single gene. Common obesity, therefore, is considered to be polygenic, or coming from multiple factors. What is concluded from this research is that genetic factors offer only a small contribution to obesity risk, and that “our genes are not our destiny.” Studies have demonstrated that there are many people who carry the genes that influence obesity that do not become overweight. More generally there are also people whose healthy lifestyles can unsurprisingly counteract these genetic influences.
Studies have preliminarily concluded that key changing environmental factors have largely influenced obesity prevalence, and that genetic changes are unlikely to account for that prevalence. The reasoning behind this claim is that the gene pool frequencies across a population remains, for the most part, stable for multiple generations, and that gene mutations, the likely culprit for obesity risks, take a long time to spread and manifest throughout the population. Obesity rates, however, have substantially increased in the past 40 years. It is reasonable, then, to realize that other factors of the environment have assumed responsibility. Things like decreased physical activity due to sedentary lifestyles; social, political and economic surroundings; wider access to inexpensive, unhealthy foods all provide a considerable sway over our lifestyle choices.
What is interesting is that a majority of Americans appear to share this perception of obesity. Concern over obesity in this country has achieved near parity with that of cancer. And yet, obesity rates have somehow increased. That there are cases of genetic diseases that result in obesity is indisputable. Attempting to rally around these rarer cases, however, misses the point of the arguments in favor of encouraging individuals to actively pursue lifestyles and articulate the scientific justifications behind such a plan.
Essentially, I would warn that we must first consider the objective scientific evidence on the issue before determining any sort of definitive causal relationship. This connection influences how we legislate and construct our national lifestyle and personal choices. Moreover, this awareness of the growing, clarifying scientific insights must be promoted from the bottom up. It is the everyday American that is the intended target of this information. It is the everyday American that requires the precise information to hopefully discover and rally around a healthier lifestyle. It is the everyday American that must abandon a resignation to false, immutable predetermination.
