By DR. GEORGE GROSSBERG

As a doctor who takes care of older adults, I am often asked two types of questions about drinking or alcohol consumption.

An 80-year-old male patient, who is "sharp as a bell," recently told me that for the past many years his singular vice has been having "a martini with two olives" every night before dinner. He wanted to know if this was medically acceptable, or whether he should quit.

An 84-year-old female patient, who is cognitively intact and a life-time teetotaler, had read that mild-moderate alcohol consumption (1-2 drinks/day) was good for the heart and may even decrease the risk of Alzheimer's disease.

She asks: "Would you recommend that I start having a daily drink?"

Two studies presented at the Alzheimer's Association International Conference in Vancouver on Wednesday help us to better address these questions.

One study followed a group of women 65 or older who started out as non-drinker, mild drinkers, or moderate drinkers (no heavy drinkers, please). After 20 years, they were evaluated for memory problems and dementia. The women who went from non-drinking to any level of drinking increased their chances of developing memory or dementia problems by 200 percent. Also, the women who were moderate drinkers at the start and stayed that way did not have a lower risk of developing problems than the ones who didn't drink the whole way through. So going from teetotaler to any level of drinking was actually harmful. Being a drinker from the start didn't necessarily hurt, but it wasn't protective.

A second study looked at binge drinking, or having four or more drinks at one sitting. Patients were evaluated in 2002 and followed for eight years. The study found that people who had one binge-drinking episode per month were 62 percent more likely to show memory problems than those who didn't binge drink. Those who had two or more binge-drinking episodes were 147 percent more likely to have these problems than the non-bingers. So one episode per month was bad, but two episodes was more than two times worse.

These studies confirm what we have been recommending for our patients: If you're a light or moderate drinker - 1 oz. of alcohol per day if you are a woman, up to 2 oz. for men - you don't need to change your habits. That martini or glass of wine with dinner is OK. But if you don't drink, starting alcohol consumption in your later years isn't a good idea. It may increase your risk of mental decline and Alzheimer's disease.

Neither of these studies addressed what to recommend to older patients, relative to alcohol intake, who are already experiencing cognitive decline or have Alzheimer's. Research has shown that in these individuals, no alcohol intake - or switching to non-alcoholic beers and other beverages - is best, since even small amounts of alcohol can upset their delicate cognitive equilibrium and significantly worsen cognition and even trigger behavioral problems

Dr. George Grossberg is the Samuel A. Fordyce Professor of neurology and psychiatry at the Saint Louis University School of Medicine and past president of the American Association of Geriatric Psychiatry and of the International Psychogeriatric Association (IPA).