More research supports moderate drinking

A large, ever-growing body of evidence suggests that moderate drinking - a glass or two of wine a day, a beer (or even a martini) after work a few times a week - may help people live longer and healthier.

That's probably good news to folks who booze it up a bit over the holidays, assuming they don't overdo it on the eggnog or Champagne. But the evidence isn't quite strong enough, and the risks associated with drinking alcohol are serious enough that no one's recommending non-drinkers start a new habit.

And binge-drinking? Pretty much always a terrible idea, say public health experts.

Alcohol is a fuzzy topic in public health. There are undoubtedly some health benefits and most people can drink safely and enjoy it. But it's also connected to tens of thousands of deaths every year - from drunken car crashes, mostly, but also alcohol poisoning, liver disease and various types of accidents.

"If you're looking to reduce your risk of a stroke or heart attack, take a baby aspirin a day. It's more effective than alcohol and there's no risk of addiction," said Keith Humphreys, a research scientist and professor of psychiatry at Stanford University School of Medicine. "These studies on the health benefits just let those of us who like a glass of wine now and then justify it."

Some of the most recent reports on health benefits associated with alcohol come from the Nurses' Health Study, a database of more than 84,000 nurses who have been followed for more than 20 years to study a variety of health behaviors and outcomes.

Study results released in November showed that women who had about two drinks a day were up to 28 percent more likely to live to age 70 or older than women who drank only once or twice a week, or who drank in occasional binges. Another study, also released last month, found that women who had about one drink a day had a 20 percent lower risk of stroke compared with women who never drank.

Research has shown a connection between reduced rates of disease and alcohol consumption for decades - but "connections" aren't the same as hard scientific evidence, many scientists point out.

"The problem with the studies is they're not double-blind, placebo-controlled studies," said Dr. Don Mordecai, director of mental health and chemical dependency services for Kaiser Permanente Northern California. "These people who are light to moderate drinkers, they tend to be healthier in a lot of different ways, and they tend to have healthier habits."

The main argument that public health experts use against drinking - or at least against encouraging people to drink - isn't the threat of alcoholism or long-term organ damage from heavy drinking. It's that some people, especially this time of year, drink more than they should. And they do really stupid things when they're drunk.

In October, the U.S. Centers for Disease Control and Prevention put out new warnings against binge drinking, which they label as a cause in more than 79,000 deaths a year in the United States. The CDC reported that more than 15 percent of adults engage in binge drinking every year.

Binge drinking is defined as having more than four drinks at a time for women, and more than five drinks at a time for men - or essentially, reaching the legal limit for being too drunk to drive. Even one episode of binge drinking a year is considered unhealthy, according to the CDC.

That may seem a little extreme, some doctors and public health experts say. But the CDC and other public health groups are looking at binge drinking on a national scale, and evidence shows that people who drink too much in one sitting are simply more prone to injury or death.

"It's just epidemiology," said Humphreys. "We're just trying to give people accurate information. You look at the group of people who drink that way, you add up the car accidents, the stumbles down the steps, and someone in that group will have more incidents. It's also a fact that many, many people in that group are fine."

Even staunch public health advocates admit that it's no fun to tell people they can't ever overindulge in alcohol.

And there's even an argument to be made for drinking to loosen up social behaviors, said Selena Bartlett, director of the preclinical development group at the Ernest Gallo Clinic and Research Center at UCSF. The center, which takes its name from the wine maker who was also a longtime university donor, conducts research into addictive behavior.

For some people, a drink or two makes them a little more outgoing and relaxed - and if that means they engage with other people more and make more friends, that might not be a bad thing. Within reason.

"More and more research demonstrates that social interaction provides a lot of health benefits. Some people find it hard to engage socially and with one drink, now they can," Bartlett said. "But it's a tricky line to go over, because some people can have one and feel great and that's it, and for others, there's no stopping."

E-mail Erin Allday at eallday@sfchronicle.com.

This article appeared on page A - 1 of the San Francisco Chronicle