Travel alerts are not often issued for Americans in their own country, but the recent mapping of obesity prevalence by state may prove to be an exception. The Centers for Disease Control and Prevention (CDC) report charting state and regional variance in obesity among U.S. adults might serve first and foremost as a warning against visits to the South, where nearly 1 in 3 Americans are obese. But since when has obesity been a disease you can catch?
According to the CDC, an obese adult is one whose ratio of weight to height (or BMI: body mass index) is 30 or higher. This measure sets no low bar; at just 5’9”, for instance, you need to top 200 pounds to count as obese. Nevertheless, since we rounded the past century with a girth spurt, the number of obsese Americans has swelled from roughly 1 in 8 in the 1980s to more than 1 in 3 today.
Most astonishing, though, is not just that we have been gaining weight and fast, but that we have been gaining it together. The CDC map reveals spread patterns for obesity similar to those for communicable disease: obesity is thriving by proximity.
In the Southwestern U.S., where the prevalence of obesity stands at about 1 in 5, the lowest rate of any region in the country, there is very little variance between neighboring states. Such uniform distribution holds for the North and Midwest, where in just about any state, 1 in 4 adults boasts a spring-bending BMI. Perhaps unsurprisingly, the outbreak is worst in the South, but even there the regional trend is homogenous across states. Americans appear to stretch in accordance with those around them.
Other assumed risk factors for obesity, such as levels of income and education, are often invoked to explain these patterns. But according to the CDC, socioeconomic status may ultimately explain very little. Most obese adults are not low income and over the past several decades, the rise in obesity rates has claimed adults across all education levels. While disproving these hypotheses may not uncover the ultimate cause of obesity, it could offer clues: perhaps risks for obesity lie in the environment, not in the individual.
Recent studies demonstrate that our access to food outlets, coupled with our social milieu that establishes health norms, influences our eating patterns. In a neighborhood where grocery stores and other healthy food options are hard to find — what we now call a "food desert" — the risk of obesity shoots up. Residents are put at even greater risk when their friends gain weight, which is unsurprising given changes in weight perception: those identified as obese in the 1980s considered their weight to be “about right” by the turn of the century.
Evidently, where you are affects what you do. But when the slimmest state today (Colorado, at 20.7% obese) would outweigh any other from just over a decade ago, whatever state you're in is, invariably, fat. And if fried butter on a stick at the state fair in Iowa (a state which is 29% obese) is any indication, you may find that even if you don't fit in old belts and bus seats, in America, you do fit in.