Wednesday, April 22, 2009
We all hate fat people. That's a given. But why do we hate fat people? (and by "we" I mean white, Anglo-Saxon, male researchers). The answer is simple: We're not allowed to hate black people. Don't believe me? Let's examine the stereotypes. "Black people are lazy" is now "fat people are lazy." First it was "black people like chicken." Now it's "fat people have a genetic condition that makes fried chicken taste delicious." There are also historical similarities between the two groups. There used to be a "poll tax" to stop black people from voting. Now we have a "twinkie tax"(1) to stop fat people from eating. Just like the "black codes" that stripped black people of their individual liberty, we now have "food codes"(2) that strip fat people of their dietary liberty. Then there was the "science" that proved "negro inferiority"(3). Now, we have the "science," which proves that fat people cause global warming (4). At least that's what a new article published in this April's International Journal of Epidemiology suggests (I like how the press release was published on Earth Day*).
So why are we allowed to hate fat people? Supposedly, it's unhealthy, "world-wide, over 1 billion adults are overweight and around 300 million are obese. The increasing global relevance of overweight and obesity has serious implications for health, increasing the risk of type 2 diabetes, cardiovascular disease, stroke, and some cancers."(4) As it turns out, "normal people" aren't that healthy either (5a, 5b, 5c). The other reasons that make it acceptable to hate fat people, they're unattractive and fat jokes are funny, were not examined in this study.
"There is some evidence that the entire population distribution of BMI may be shifting upwards, increasing the risks of disease for the whole population and not only for the most overweight in the upper tail-2"(4). In layman's terms, people are getting fatter. However, take a look at the title of the study cited, "Weight gain and its predictors in Chinese adults." Apparently, what happens to Chinese people can be generalized to the global population. This is another example of not appropriately supporting your statements.
So why should we direct our liberal rage at fat people? "The upward shift in the population distribution of BMI could also have important environmental consequences. Food production accounts for an estimated 20% of global greenhouse gas (GHG) emissions and food consumption is intimately linked to BMI." (I question that 20% figure; 6).
Here is the stated goal of study, "to estimate the impact on GHG emissions of increase in the population distribution of BMI." How can you do a study about fat people and global warming and not examine flatulence? According to angry liberals, cow flatulence is bad for the environment (cow). Since the fat equivalent of "jungle bunny" is "cow," it seems only natural to study this too.
Here's why it was not studied: NO people and their habits (or flatulence) were actaully studied. They assumed the characteristics of a "normal adult (30-59) population of 1 billion people with mean BMI of 24.5 kg/m2 and 3.5% obese, with a corresponding overweight population with mean BMI of 29.0 kg/m2 and 40% obese." While certain human characteristics such as height and weight are normally distributed, other examined behaviors in this study such as driving, walking, and flying are not normally distributed (or they could be, I just made that up). Other methodological problems can be seen here.
"Our normal population BMI distribution reflects the UK situation in the 1970s and our overweight population BMI distribution reflects that predicted for the UK in 2010." Here's something that has never been made clear to me; in research that includes obesity data collected before 1998, what definition is being used? The definition changed after 1998 (7, 8). Current estimates indicate that approximately 30% of Americans are obese (9). However, using the pre-1998 definition, approximately 12% of Americans are considered obese, when in 1980, 14% of Americans were considered obese (10). Has the prevalence of obesity increased or decreased?
The remainder of the paper is an exercise in statistical masturbation. They concluded that "compared with a normal population distribution of BMI, a population with 40% obese requires 19% more food energy for its total energy expenditure. Greenhouse gas emissions from food production and car travel due to increases in adiposity in a population of 1 billion are estimated to be between 0.4 Giga tonnes (GT) and 1.0 GT of carbon dioxide equivalents per year." Here's the Cliff's notes version (i.e., minus the soft bigotry of scientific jargon): fat people eat more, walk less, drive and fly more, and are affected by gravity more than "normal" people.
Although the authors acknowledge that all of their "assumptions" can "be questioned," (because there is no scientific rationale to that they're correct), they still state that "the assertion that increasing population adiposity (i.e., people are getting fatter) will result in an increase in GHG emissions is justifiable and provides further evidence of the link between human health and climate mitigation (i.e., global warming)."
Since these teabaggers are allowed to make wild assumptions in the name of science, I can do the same. Here is a picture of Al Gore when he was Vice President (11). He's thin. At 6'1" and 195lbs, his BMI was 25. Current standards classifies this as overweight. Here is Al Gore now (12). He's fat. I'm going to assume, based on these pictures, that he has gained a good 35 lbs. At 6'1" and 230 pounds, his current BMI is 30. That means that he's obese. Therefore, I can concluded that Al Gore's fat assedness (i.e., increased adiposity) is leading to an increase in GHG emissions, providing further evidence of the link between human health and global warming (i.e., climate mitigation). Perhaps I'll submit this to the International Journal of Epidemiology. If I'm lucky, they'll publish it on Earth Day next year.
Edwards, P., & Roberts, I. (2009). Population adiposity and climate change International Journal of Epidemiology DOI: 10.1093/ije/dyp172