As the Christmas and New Year holidays approach in Mexico, health officials are expressing concern that too much holiday cheer could lead to sickness, injury, and death. The urge to imbibe spirits has ancient roots in many parts of the country.

In one of Puebla's many small bars, the regulars have gathered at night to drink the milky looking beverage called pulque, a crude concoction that was invented by the ancient Aztecs centuries before the arrival of Europeans. The alcoholic drink is made from the fermented juice of the maguey plant.

Mexico's other famous liquors, mescal and tequila, are also derived from maguey, but they are distilled and sometimes aged. Pulque is a much less refined drink and is favored by low-wage workers and many people who dwell in tradition-bound rural communities.

Mexican health officials are warning consumers of such crude spirits to be careful because some batches contain contaminated water or other harmful substances.

The head of Mexico's National Council Against Addictions, Guido Belsasso, says pulque could ruin the holiday celebrations for some people. He says the six million Mexicans who consume such beverages should be careful because evidence shows that these drinks are often adulterated and they are the ones that cause the most damage.

Back at the pulqueria, however, the night manager, Graciela Gonzalez Munoz says she serves only the pure, clean product. She says her supplier uses no water, just pure maguey and that it is not contaminated in any way. She says she is 70 years old and has been drinking pure pulque for most of her life. Her customers shout in agreement. They also offer testimonials to the potent potable, which some even claim has medicinal effects.

Pulque consumption is on the decline in Mexico as most people looking to quench a thirst for alcoholic refreshments now favor beer, whiskey, rum and tequila, all of which can be found in cantinas and bars. Most of these establishments would never allow such a low-status drink as pulque through their swinging doors.

The traditional drink of the Aztecs continues to hold a core clientele in the central states of Puebla, Hidalgo, Tlaxcala, and the state of Mexico.

But For Guido Belsasso the danger of holiday drinking goes far beyond the quality and social status of the beverage. He says the quantity of alcohol drunk by Mexicans has doubledfrom 3.7 liters consumed in 1970 to a current level of 5.8 liters per person.

He says that excessive drinking is a problem every bit as serious as drug abuse in Mexico. He notes that Mexico is in the top position worldwide for cirrhosis of the liver, a condition associated with alcohol abuse. He also cites statistics showing that drinking is the chief cause of death among youths involved in vehicular accidents.

Mr. Belsasso and other officials are calling for Mexicans to use restraint and caution as they celebrate during the coming holidays so that they will be around to enjoy holidays in the future.