If you invest in casual dining chains specializing in Italian cuisine, your four-letter word vocabulary may include Buca (NASDAQ:BUCA) -- and a few more unmentionables.

The operator of the Buca di Beppo and Vinny T's of Boston chains posted a huge fourth-quarter loss on the heels of an asset impairment charge. Even before the one-time hit -- and an income tax benefit -- the company closed out the period in the red.

With same-store sales down 7% at its flagship restaurants and 4% at Vinny T's, the company is feeling the wrath of the latest dieting craze -- Dr. Atkins' inspired carb-counting. Apparently, with their fluffy pastas and doughy breads, folks are taking the barcheta to the bruschetta and saying farewell to farfalle.

Buca's doing what it can. It's working on a Buca Small menu to encourage lighter portions. It will also slow expansion of its 105-unit empire to just four new locations this year. While eatery openings propped up sales by 7% to $257 million last year, it seems wise to focus on the problem at hand before multiplying it.

Other restaurant operators have casual Italian concepts in the mix. However, Darden Restaurants (NYSE:DRI), Brinker International (NYSE:EAT), and Outback Steakhouse (NYSE:OSI) are diversified with chains that will help pick up the pasta-flipping slack if the low-carb dining trend sticks.

Back to Buca, which I figured was Italian for "mouth" until Babelfish corrected me with the proper translation: "hole." Investors have to wonder when Buca will get out of this buca. The company now expects a small loss for the current quarter. Analysts were expecting a modest profit.

Mangia gets mangy on the company's cash-poor, debt-rich balance sheet. That's yet another reason for Buca to curb expansion for now. While Buca has more than a reasonable shot to bounce back, buying into slumping dining concepts is more savory after the menacing morsel has time to be digested. So take it easy. Buca isn't going anywhere any time soon.

Rick does not own shares in any company mentioned in this article. His stock holdings can be viewed online, as can the Fool's disclosure policy.

Is it time to blast the low-carb trend for hurting sales at Buca, or is it time to embrace that form of dietary living? Are all carbs bad? Do carb-free alternatives taste good? All this and more -- in the Low Carb Way of Life discussion board. Only on Fool.com.