Americans—along with everybody else in the industrialized world—have been growing fatter over the last couple of generations. But why? Dozens of different causes have been suggested: It’s because food is less expensive and more readily available than ever before in history, so we generally eat more than our ancestors did. Or it’s because of sedentary lifestyles—our televisions, computers, desk jobs, lengthy car commutes and all the other reasons people sit still for hours at a time, rather than move around and burn calories.
These factors surely contribute to our expanding waistlines. But might environmental pollution also be a culprit? Because it’s not just people getting fatter in the modern world—animals are, too. Our pets, our laboratory animals, even the unwanted feral rats infesting our cities are all bigger than they were in our grandparents’ day, and maybe some of this comes from chemical pollutants that imitate various “fat” hormones naturally produced by our bodies.
Unlikely though this might sound, over the past decade and more there’s been a wide variety of research studies which seem to support the theory. Over at ProPublica, reporter David Epstein collected and summarized a sample range of these reports in a thought-provoking investigative article titled “Do These Chemicals Make Me Look Fat?”
To share just a couple of statistics: the National Pet Obesity Survey claims that over 50 percent of American cats and dogs are obese. Also, there exists a “National Pet Obesity Survey.”
Despite having pretty much the same diet and lifestyle as they ever did, American laboratory rats have grown steadily fatter over the last 30 years (which is several generations, for rats). This might, possibly, be blamed on other factors present in a laboratory environment (including exposure to antibiotics), except that feral rats studied in Baltimore have also grown fatter—without exposure to antibiotics or other factors present in a lab-rat lifestyle.
But today’s environments—whether natural, urban or laboratory—are all contaminated by trace amounts of various pollutants, including growth hormones fed to livestock, and toxic ingredients in widely used insecticides, fungicides and other anti-pest poisons. These pollutants, in turn, can affect people’s (or animal’s) bodily systems in a variety of ways, either mimicking or suppressing the functions of various hormones.
As obesity researcher Emily Dhurandhar said to ProPublica, “Obesity really is more complex than couch potatoes and gluttons.”