(FORTUNE Magazine) – Food and beverage companies have discovered one sure way to fatten their bottom lines: Offer diet-conscious consumers a light alternative. But those light or lite labels that suggest lower levels of calories, fat, or sodium can be downright misleading. Van de Kamp says that light flounder means lightly breaded. That frozen dinner has 193 more calories than the company's regular catch. And a can of Michelob Light packs nearly as many calories as one of Pabst Blue Ribbon, a regular brew. (See table.) A congressional bill, the Lite Food Labeling Act, would clear up the language and the confusion. Introduced by Representative Jim Cooper (D- Tennessee), the bill would restrict the use of the word light to products that have a third fewer calories, half the fat, or three-quarters less sodium than a company's standard counterpart. The bill would also set standards for lean and extra lean: no more than 10% fat and 5% fat, respectively. Now pending in three committees, the bill is expected to get a hearing when the new Congress convenes early next year. Among the groups that have lined up to support Cooper's Lite bill are the Consumer Federation of America, the American Public Health Association, and the American Heart Association. Memories of his bachelor days when he dined regularly on frozen dinners inspired Cooper, 32, to sponsor the bill. The 6-foot-tall Congressman says he used to shop conscientiously for foods carrying lite or lean labels to keep his weight at 175 pounds. It took his marriage 18 months ago to shed light on lite and lean. At his wife Martha's urging, he began reading the fine print on some of his favorite fare. He says, ''The words light and lean are very sexy, and they seduce a lot of people.''