By Ben Adler
In Monday’s New York Times John Tierney asks why Americans have kept gaining weight over their European peers even as they have become significantly more health-concious than most Europeans. Without so much as a passing nod to the more likely culprits, such as corn subsidies or suburban sprawl, he posits that it is because Americans pay too much attention to the fat content of their food and consequently feel free to eat much more of it.
But his evidence is so shockingly thin that I’m surprised his column made it into the paper. He asked 20 pedestrians in my native neighborhood in Brooklyn how many calories a pictured salad has and 20 different people on the same street how many the meal has when the salad came with crackers marked “Trans Fat Free.” The guesses were actually lower for the picture with crackers even though that meal has more calories. Then he did the same experiment in Times Square where almost everyone is a tourist and many are foreign, and found that they were more likely to correctly assign higher caloric counts to the meal with crackers. From this scrawny reed and he spins out an argument that takes him to the wholly unsubstantiated suggestion that New York’s trans fat ban might cause New Yorkers to gain weight.
Here’s Tierney’s nut graf:
So might New York’s pioneering ban on trans fats have done more harm than good? Did it encourage people to eat more calories (and other fats that some scientists argue are no less harmful)? Did people start eating French fries — hey, they’re trans-fat free now! — and reward themselves with dessert? I can’t pretend to know the answers after our little experiment, which hardly constitutes peer-reviewed research. But the results were statistically significant.
They are not. Firstly he does not even prove that his Times Square respondents were all or even mostly foreign. Nor does he pay any attention to which countries they come from. He doesn’t even consider the fact that many people on the street in Brooklyn are foreign-born immigrants. Nor does he show any evidence that he is comparing like with like. Is it possible that one group being older or younger on average might have skewed the results? Also his sample size is just pathetically small. Most important of all, though, is that if the tourists were indeed foreign, the whole explanation might just be that they are unfamiliar with the phrase “trans fat free,” which is something that even a Frenchman proficient in English might not fully comprehend, never mind the average non-native English speaking tourist. (I, for instance, took French for over 10 years and I do not know what the French word for “trans fat” is. In fact, most Americans may not know precisely what trans fats are.)
Tierney’s only other piece of evidence is that people who eat at Subway were found more likely to under-estimate the calories in their meal and to order unhealthy desserts than people at McDonald’s. But on the latter point it seems to me that people may feel license to order a cookie not because they think the sandwich they order is low on calories but because they feel less bloated than after a greasy burger and french fries. I know, at least, that is how I feel. While I think that Tierney’s point about misperceptions of caloric intake is valid in so far as it goes it’s just silly to seriously suggest that the trans-fat ban has actually been counter-productive because of it.