The usual January diet drill has an unusual proponent in 2010: the fast-food industry. Many of the nation's largest fast-food chains — better-known for their often fatty, high-calorie foods — are loudly touting diet and low-calorie offerings.

Familiar brands from Taco Bell to Starbucks to Dunkin' Donuts are rolling out new products and ad campaigns in an attempt lure calorie-conscious consumers during the month when the $170 billion fast-food industry typically sees sales slide.

Consumers feel fat in January. Some 61 percent would like to lose 20 pounds, says a survey from NPD Group. And 64 percent of Americans say they are taking steps to improve the "healthiness" of their diets, according to the 2009 Food and Health Survey from the International Food Information Council.

The January diet rush isn't limited to fast food. Applebee's just rolled out a menu with five entrees under 550 calories. But fast food is the culprit consumers most often link to fast calories. So, does it make sense for a dieter to go out for fast food?

One nutritionist offers a cautious maybe. "Just because something is 'low-cal' doesn't mean it's good for you," says Alice Lichtenstein, nutrition professor at Tufts University. But with the current obesity crisis, she says, "It doesn't really matter where you get your food from. What's most important, in the long run, is the total number of calories you consume."

Here's who's doing what:

Taco Bell. The chain is nationally rolling out a Diet Drive-Thru Menu it tested last January in Omaha and Tucson. The menu has seven items with 9 or fewer grams of fat and all under 200 calories. In last year's test, repeat purchases from the menu were the highest of any product the chain's sold in 20 years, says Tom Wagner, vice president of consumer insights.

Starbucks. Tomorrow, it will roll out four hot panini sandwiches — all under 400 calories. The chain also is promoting its "skinny" lattes. These are made with fat-free milk and are sugar-free. Switching from a regular Vanilla Latte to a Skinny Latte saves 100 calories, says Katie Thomson, senior nutritionist at Starbucks.

Dunkin' Donuts. The chain today will announce that customers can order any breakfast sandwich or Wake-up Wrap made with egg whites instead of eggs. The change reduces calories by at least 25 percent, says Stan Frankenthaler, executive chef.

Subway. No surprise that Subway is hyping its well-known Fresh Fit low-fat menu. "People adjust their behavior post-holiday," says Tony Pace, who oversees Subway's consumer marketing.