Time’s John Cloud on why exercise may not be the secret to weight loss:

The basic problem is that while it’s true that exercise burns calories and that you must burn calories to lose weight, exercise has another effect: it can stimulate hunger. That causes us to eat more, which in turn can negate the weight-loss benefits we just accrued. Exercise, in other words, isn’t necessarily helping us lose weight. It may even be making it harder.

And our bodies weren’t exactly built to lose weight in the first place:

Fundamentally, humans are not a species that evolved to dispose of many extra calories beyond what we need to live…We have so little brown fat that researchers didn’t even report its existence in adults until earlier this year. That’s one reason humans can gain weight with just an extra half-muffin a day: we almost instantly store most of the calories we don’t need.

As a massively, to a point nearly unhealthy, pale skinny nerd, I generally have a less than easy time sympathizing with the obese. But the more I read, the more I begin to realize just what a terrible hill folks have to climb if they weren’t born with the metabolism of a meth fiend.