SAN DIEGO -- Eighteen-year-old Sandra Villarda felt besieged by beer billboards on her drive down El Cajon Boulevard to San Diego City College. Every day, the ads greeted her, for Bud Light on one block, Miller Lite on the next. "Mas Calor! Mas Sabor! Mas Fiestas!" one Miller Lite billboard read. "More Heat! More Flavor! More Parties!"

There are other sights along the route, too. "I see Latino kids sipping beer out of a Coke bottle," says Ms. Villarda, who recently joined the San Diego Youth Council, a group that promotes an antialcohol-abuse message. "There is a lot of pressure to drink in this community," she adds.

Facing stagnant beer sales, an aging population and the blossoming appeal of wine, the nation's biggest brewers are aggressively courting Hispanics, the fastest-growing and youngest population group in the U.S. The brewers' efforts, including a burst of advertising aimed at Spanish-speaking consumers, have rankled community health activists and rekindled the debate about when marketing crosses the line into the realm of unfairly targeting an ethnic group.

Last year, Anheuser-Busch Inc., the St. Louis brewer of Budweiser and Bud Light, created a new division dedicated to marketing to Hispanics and announced it would boost its 2006 ad spending in Hispanic media by two-thirds, to more than $60 million. SABMiller PLC's Miller Brewing Co. signed a $100 million, three-year ad package with Spanish-language broadcaster Univision Communications Inc.

Marlene Coulis, vice president for brand management at Anheuser-Busch, says, "We would disagree with anyone who suggests beer billboards increase abuse among Latino or other minority communities." She adds, "It would be poor business for us in today's world to ignore what is the fastest-growing segment of our population."

Advertisers find the Hispanic population enticing because its spending growth will far outstrip that of the general population for the foreseeable future, says Jeffrey Humphreys, who monitors Hispanic demographic and economic trends at the University of Georgia's Selig Center.

"If you want to be successful, you must have a marketing and sales effort among Hispanic consumers," says Paul Mendieta, director of Hispanic marketing at Coors Brewing Co.'s Molson Coors unit.

But some in the Hispanic community are shrinking from the beer industry's embrace because of another demographic reality: Nearly half of all Hispanics in the U.S. are under the age of 21. Activists are raising public-health concerns about the beer ad blitz on the grounds that it targets a population that skews young and is disproportionately likely to abuse alcohol. A 2004 survey of eighth-grade students found that Hispanic youth are much more likely to drink alcohol and get drunk, and to engage in binge drinking, than their white or black peers.

At the Mental Health Services Teen Center in San Marcos, an ethnically mixed suburb of San Diego, 17 of the 35 adolescents undergoing treatment for alcohol and drug abuse are Hispanic. "Increasing numbers of those seeking treatment are Hispanic girls," says Ray DiCiccio, executive director of the nonprofit Policy Panel on Youth Access to Alcohol, which provides prevention and research programs to San Diego County.

"Latino youth are drinking more than black or white youth, with all the concurrent negative health and social consequences," says Katherine Culliton, an official of the National Latino Council on Alcohol and Tobacco Prevention, in Washington. "We believe this is a result of beer companies aggressively targeting Latino youth."

Executives at beer companies bristle at the notion that there is a link between beer ads and alcohol abuse among young Hispanics. "When it comes to preventing underage drinking, we should focus on restricting access, not censoring advertising," Ms. Coulis says. Brewers say they finance ads promoting designated drivers and discouraging underage drinking. Anheuser is one of the largest corporate contributors to the Hispanic Scholarship Fund and a major donor to the Mexican American Legal Defense and Education Fund, an advocacy group.

Recent research has attempted to establish a link between exposure to alcohol ads and consumption by youth. Twelve- to 20-year-old Latinos see and hear more alcohol ads per capita than young people in that age group overall, according to a 2005 report by the Center on Alcohol Marketing and Youth at Georgetown University.

One study, published in the Archives of Pediatrics & Adolescent Medicine in January and funded by the National Institute on Alcohol Abuse and Alcoholism, found greater exposure to alcohol ads contributes to an increase in drinking among youth. From 1999 to 2001, 15- to 26-year-old individuals in 75 top media markets reported the number of alcoholic drinks consumed in the prior month. Subjects in markets with more alcohol ads showed increases in drinking into their late 20s. In markets with fewer ads, the subjects' drinking plateaued in their early 20s.

Advertising-related or not, drinking rates among Hispanic teens are alarming. In a 2004 survey by the University of Michigan funded by the National Institute on Drug Abuse, 23.5 percent of Hispanic eighth-graders said they had drunk alcohol over the past month, compared with 19.2 percent of whites and 16.2 percent of blacks. For beer, the rate was 18.4 percent for Hispanic eighth-graders, 13.5 percent for whites and 8.1 percent for blacks.

Anheuser's Ms. Coulis points out that the 2004 data mark a decline from 1992, when the drinking rate among Hispanic eighth-graders was 31 percent. She cites a consumer survey in which Hispanic youth say their parents are the top influence in their decision about whether to drink alcohol.

A Miller Brewing spokesman says, "In order to cut underage drinking, you have to cut access to all alcohol from parents and peers."

San Diego passed a local ordinance in 2000 banning alcohol billboards within 1,000 feet of schools, playgrounds and churches. But in June 2001, the U.S. Supreme Court knocked down similar restrictions on cigarette billboards. Billboard companies challenged the San Diego ordinance, and in 2002 the two sides reached a settlement. In 2003, the city modified its ordinance to 500 feet, the same standard the beer industry has incorporated into its voluntary advertising guidelines.

Activists are taking on Spanish-language beer commercials. The National Latino Council in February complained to the Federal Trade Commission about a Bud Light commercial that it says is a thinly veiled endorsement of underage drinking. In the spot, which ran in November during Univision's broadcast of the Latin Grammys, a man brings two six-packs to a garage where three guitarists and a drummer are having a band practice. The council said the musicians look like teens and the man like a father, and that the spot lacked the tag line about responsible drinking that beer makers include in many English-language spots. It asked the FTC to investigate that spot and others running on Hispanic media during shows with large audiences of underage viewers. "All we want is for the industry to follow the same standards as it does in other communities," says the council's Ms. Culliton.

Anheuser said in a statement that it puts responsibility messages in "all advertising and point of sale materials world-wide." Acknowledging that a spot may have run without such a message, Anheuser says it began phasing in the policy only last year in January, 10 months before the awards-show broadcast.

Last month, the Beer Institute, a trade group, appointed an independent review board to assess complaints about beer ads. "We had been nudging them since 1999," says Janet Evans, a senior attorney at the Federal Trade Commission. "We're pleased they took this step."