In Slate:

the source of America’s obesity epidemic wasn’t portion size, or lack of exercise, or the decline in smoking. It was the invention of the automatic transmission. Here I was, the typical, atrophied American, barely able to press the clutch without my slack muscles begging for relief. Automatic transmissions became widely available in the 1940s. Over the decades, as Americans have increasingly embraced them, they’ve increasingly increased. Since you need both hands to drive a stick shift, there’s no way you can also be sucking down Slurpees and shoving in Big Macs. It’s because of automatic transmissions that we’re becoming blob people who will soon have to be hoisted into our behemoth vehicles.

Well, it’s a point of view.