Jill at Feministe says that a “very questionable” new study which found that obesity can “spread” across social networks makes her feel as though it must be “I Hate Fat People Week.” But isn’t this just an inversion of the very same story everyone pretty much accepts as an account of why some people become unhealthily skinny? That is: Exposure to lots of images of people who are aberrantly thin creates a skewed impression of what is “normal” or “attractive,” causing some people to go to extremes to conform to the unrealistic standard.

Unless you think that only celebrities influence what people regard as within the range of “normal,” or that this sort of influence can only work in one direction, it seems perfectly natural to expect that there would be a gradient here, such that people whose friends are mostly heavier would be less likely to feel pressure to check increases in their own weight. If the first mechanism is real, the second should be also. I’m inclined to agree with Wired‘s blogger: The only “questionable” thing is why we’d regard this as news at all.

Incidentally, while Jill’s right to emphasize that a great deal of the variance in weight is just the luck of the genetic draw, this passage strikes me as rather backwards:

And, as many overweight — and average-weight — people will tell you, dropping pounds isn’t easy. I’m not overweight, I work out four times a week, I eat fairly well, I walk just about everywhere (including up the stairs to my sixth-floor apartment), I have a normal metabolism and I still can’t lose even very small amounts of weight (a few pounds) without some serious effort.

Well, yes, of course—because Jill is already in shape. Small drops in weight are going to cost her a lot of effort for the same reason that it’s very difficult to get appreciably better at (say) guitar playing if you’ve already been practicing daily for years, whereas a beginner on the same regimen would improve quite rapidly. I, by contrast, am pretty sedentary (though relatively lucky metabolically) so if I find myself getting a bit flabby, going from almost-no-exercise to something as mild as yoga twice a week makes an appreciable difference.