By Patrick Appel

A reader writes:

It never fails to impress me the fact that people see a journal article and then turn their critical reasoning skills off. Looking through the actual paper in question, it'll be figure 1 that's giving the headliner quote of 86% fat by 2030. Except that this is wrong on two fronts.

First, the 86% is actually for obese *plus* overweight. The actual obese projection is only 50% by 2030. OK, somewhat nit-picky, but I expect precision on a blog at the Atlantic.

Now the kicker: these are *linear* extrapolations, taken out well beyond where they actually tell us anything. The tell-tale hint? Take those projections out another 15 years and they say the overweight plus obesity fraction will be 100% before 2045. Yes, that's right. Not a single healthy person left alive in the US. Marathon runners? Triathletes? Starving supermodels? Richard Simmons? All of them obese. Presumably from the fresh vegetable blight of 2040, forcing every last one of us to subsist entirely on Chicken McNuggets and Spam.

Oh, and that trend they're talking about is extrapolated from 3 data points. Sure, it's suggestive, but I wouldn't scream bloody murder from these stats.

What's particularly galling is that this is appearing in the *epidemiology* section of the journal, since epidemiologists have very nice models and methodologies for dealing with saturating disease spread.

Yes. Chalk this one up there with, "According to current trends, housing prices will keep rising, allowing us to take on LOADS of bad debt!"

(gets off soap box)

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