In case you haven't heard about low-carbohydrate diets, let me lift that rock you've been living under. It seems like every food maker and restaurant has an Atkins-friendly selection, and even beer makers have joined the fun, touting the benefits of beer as part of a carb-counting diet.

The low-carbohydrate push began in earnest last year. During the summer of 2003, Altria Group's (NYSE:MO) Miller Brewing became the first beer company to tout a traditional light beer, Miller Lite, as a low-carb product. So far, the campaign has been successful, boosting Miller's share of the light beer market. At about the same time, Anheuser-Busch's (NYSE:BUD) low-carb alternative, Michelob Ultra, debuted in the most successful launch of any new beer brand since Bud Light. All told, there are over a dozen low-carb beers vying for attention on store shelves.

It may seem odd to think of beer as diet food, since it really isn't. But light beers are truly low in carbohydrates, and if drunk responsibly, won't pack pounds on you. Bud Light has just 6.6 grams of carbohydrates in a 12-ounce can, and a 12-ounce Michelob Ultra contains only 2.6 grams, about the same as a dill pickle. I don't know about you, but I much prefer watching the NCAA Tournament with a cold beer than a dill pickle.

Besides the fact that healthy living is important, the market for low-carb products simply can't be ignored. While most analysts think it's too early to tell how big the low-carb beer market could be, Anheuser-Busch is already claiming 2.1% of supermarket beer sales for Michelob Ultra, Rolling Rock's Rock Green Light has shipped over a million cases in less than three months, and Coors Brewing's (NYSE:RKY) Aspen Edge will be nationwide by the end of the year. Decades have passed since the industry was this excited about a new product category.

Beer makers have been smart to jump on the low-carb bandwagon now, before the fad burns out. After that, maintaining market share will have everything to do with taste, as quality light beers have a long history of success. Luckily, these beers don't lack for taste or quality. Ironic, isn't it, that beer may end up as a principal long-term beneficiary of the low-carb craze?

Talk about all things Bud on the Anheuser-Busch discussion board.

Fool contributor Chris Mallon abhors dieting, and prefers heavy beers he can drink like a meal. He owns shares of Anheuser-Busch and Altria Group.