(FORTUNE Magazine) – The popularity of low-carbohydrate/high-protein diets has had an unexpected side effect: a surge in pork-rind sales. The salty snacks have about nine grams of protein per serving and no carbohydrates, making them ideal for carbo-restrictive weight-loss regimens like the Zone and especially the Atkins diet, the latest book version of which has ranked among the nation's bestsellers for nearly two years.

Pork rinds--pieces of cured, smoked pork skin fried in their own fat--may be an unlikely linchpin for a diet revolution, but they're a good business to be in right now. Sales in the $355 million category were up 13% in 1998, and preliminary indications point to similar growth in 1999. "We think a lot of it is due to these diets," says an industry spokesman.

If this all seems like a bit of a head scratcher, imagine how it sounds to pork-rind manufacturers, who suddenly have a weight-loss product on their hands. "We used to laugh because our customers didn't pay attention to diet--they just knew what tasted good," says Bill Connor, VP of sales for Evans Food Products, the largest private-label pork-rind maker. Connor, who says his sales are up about 20% and attributes almost all of it to the Atkins diet, jokes that his typical consumer used to be "the guy with a gun rack in his pickup truck." And maybe he still is--only now he's driving his pickup to the gym.

--Paul Lukas