Can a light beer have about the same number of calories as a regular beer?

Yes, indeed.

A 12-ounce serving of Michelob Light, for example, has 134 calories--only 2 calories less than the same amount of Pearl regular beer and only 6 less than Pabst regular, according to the Center for Science in the Public Interest, a consumer group that has petitioned the U.S. Bureau of Alcohol, Tobacco and Firearms for improved beer labeling.

At present, there is no standard government definition for products that are labeled as light beer--although light beer typically is depicted in advertisements as a low-calorie product.

"Without a standard, some consumers may believe any brew called 'light' is low in calories," said Bruce Silverglade, CSPI director of legal affairs.

In fact, there is a plethora of light beer products that vary enormously in calorie content.

Here are two examples, based on a random survey of various beers:

* Some light beers have nearly twice as many calories as some other light beers. Pearl Lite, for example, has 68 calories per 12-ounce serving, compared to 134 calories for that amount of Michelob Light.

* Michelob Light, in fact, has a higher calorie count than some regular beers. It has one more calorie than the 133 in the regular Heidelberg, which is distributed in Northwestern states.

Under current BATF regulations, any beer or wine can be advertised, labeled and sold as light so long as the number of calories is listed on the product label. No calorie disclosure is required, however, for regular beer or wine.

Consumers who want to find out how many calories are in a regular beer can write to the brewer for information, but it is up to the company to decide if it wants to make the calorie count available.

To clear up some of the caloric confusion about beer, a coalition of consumer groups led by the CSPI has asked the BATF to require calorie disclosures on all alcoholic beverages, regardless of whether they are sold as light or as regular.

Dot Koester, a public information officer for BATF, said the agency is considering revision of its rules. A final decision is expected this summer.

Meantime, the CSPI is continuing its campaign to get ingredient labeling on beer, wine and other alcoholic beverages.

BATF originally issued an ingredient regulation, designed mainly for drinkers with allergies, under the Carter administration in June 1980 after a decade of study. After the 1980 presidential elections, BATF officials, acting on an executive order from President Reagan to reduce federal regulations, rescinded the requirement.

CSPI the sued BATF to reinstate the regulation, which said liquor manufacturers had to list ingredients used in wine, liquor and beer or print an address on cans and bottles telling consumers where such information could be obtained.

On Feb. 9, U.S. District Judge John Pratt ruled BATF "acted in an arbitrary and capricious manner" in rescinding the earlier ingredient regulation. The judge said BATF must issue the ingredient labeling rule no later than Feb. 8, 1984.

Koester said BATF hasn't decided if it will appeal Pratt's ruling.