June 11, 2012
The average American consumes about 175 calories per day in sugary soda, at least according to the numbers presented by Mayor Michael Bloomberg at the recent roll-out of New York City’s anti-obesity campaign. Where do these statistics come from, and how accurate are they? After all, we can measure how much soda is being poured into the system, how many 12-ounce bottles and cans are sold on the open market (so-called “dispersal” data), but no one’s actually measuring the volume going down our collective hatch (“consumption” data). Moreover, if you ask city residents, they’ll tend to say, “Oh no, I don’t drink soda. I’m on a liver and cottage cheese kick.”
This phenomenon of underestimating junk food and overestimating healthy food in self-reported dietary surveys is known as the “Lean Cuisine syndrome.”
William Rathje, a forefather of modern garbology (the academic study of garbage, not a fancy name for street-sweeping), gave the phenomenon its name in his 1992 book Rubbish!. After examining trash bags full of soda cans and liquor bottles, Rathje found that what we claim to have eaten and drunk rarely lines up very closely with the actual stuff stuffed in the trash bag—especially when it comes to soda and liquor.
In other words, we are what we eat, but we tell the truth about it only in what we leave behind. Rathje is not a psychologist and doesn’t spell out exactly why we lie, but perhaps it’s a coping mechanism. After all, it’s tough to own up to another statistic—that a third of our food goes to waste.
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