Apparently this photo is a screen cap from a documentary made back in January 2004. I've had a dig around but haven't been able to find it anywhere (Google Videos or YouTube). If anyone finds it, let me know!
DOCUMENTARY: America's Fattest City
Channel: Channel 4 104
Date: Sunday 4th January 2004
Time: 21:00 to 22:00
Duration: 1 hour.
Documentary which looks at just why obesity is now public enemy number one in Houston. For the last three years the Texas city has been named and shamed as America's fattest city with two thirds of its population overweight, and a third obese - but why?