Men’s Fitness magazine recently released a report listing the fittest and fattest of the fifty most populous U.S. cities.(1) There doesn't seem to be anything too useful in ranking fattest and fittest cities, but I'll admit that I was curious. Is my current city fatter than my hometown? How do the residents of my college city compare in size to their neighbors a few cities over?
I was surprised at the results. And you might be, too. My fellow New York City residents may be shocked to discover that our city ranks as the eighth-fattest in America. Are we really that fat?
Maybe not. A glance at the study's methodology(2) reveals that what makes a city fat or fit according to Men’s Fitness may be little more than luck of the draw. The contenders were all ranked based on their scores in fourteen equally weighted categories. They range from measures of the prevalence of obesity to the average commute time to the number of public basketball courts.
I have a lot of concerns about these criteria:
• Why are all fourteen categories weighted equally? Are statistics such as air quality (one of the fourteen measures) as important an indication of "fatness" or "fitness" as the rates of obesity in a given city? For that matter, why are categories like "air quality" included at all? Presumably, the study includes air quality because poor air quality means people get outside to exercise less often. But couldn't they exercise just as much indoors (a fact the study seems to admit in its inclusion of "number of gyms" as a criterion for determining a city's fitness). Indeed, almost all the other concerns listed below relate to criteria that have no clear link to fatness or that only affect weight when considered with numerous other confounding factors that are missing from this study.
• Does the number of gyms say anything about the quality of the gyms or the number of people they serve? Several big gyms might help keep people fitter than many smaller ones with outdated equipment.
• Do measures such as "commute time" really indicate propensity for getting fat, as the report indicates? Sure, New Yorkers spend a lot of time on the subway, but that doesn't mean they're not walking a whole lot, too.
• The number of "junk food" retailers per capita may tell you how many McDonald's restaurants you'll find in your city, but it doesn't tell you how healthy your eating options are. Looking once more at New York City, we see that we may have a lot of fast food, but we also have thousands of restaurants offering what even _Men’s Fitness_ would deem healthy foods. Just because we have a lot of "junk" food doesn't mean we don't have a good ratio of healthy to "junk" options when we dine out. And does the report take into account how many people eat at the "junk food" establishments in these cities, what they eat there (maybe a McDonald's salad?), how much they eat there, and how often? Nope.
• Worse weather may seem like it could cause a city to be fatter, but isn't that just a supposition? Any New Yorker who's had a subway shut down due to weather and has then had to walk forty blocks to work in the snow or slush can tell you that bad weather isn't always exercise-inhibiting.
• The "exercise/sport" measure takes into account the number of people participating in one of 103 sport or exercise activities. But then the "overweight/sedentary" measure includes the "percentage of the population not participating in physical activity." That sounds like double counting to me.
• The measure of health care includes the cost of doctor visits, without taking into account the relative burden of those costs on cities with dramatically different average incomes, rendering moot any measure of fitness or fatness based on health care costs.
• The criteria include a measure of the geography of the area, including such resources as ocean beaches, supposedly because people living near these resources use them to engage in physical activity. But would one necessarily get more exercise lounging on the beach than walking around a city?
Sure, a little list of "Who’s Who Among America's Fattest Cities" can be fun, but I don't know that we should take the results too seriously. There are published studies that rate areas based on legitimate measures of current weight.(3) But we're all better off worrying about our own fitness than about arbitrary rankings of fat and fit cities.
1 http://www.mensfitness.com/rankings/304
2 http://www.mensfitness.com/rankings/305
3 See, for example, http://www.cdc.gov/nccdphp/dnpa/obesity/trend/maps/obesity_trends_2003.pdf
Lynnea Mills is a research intern at the American Council on Science and Health.
