Can moderate drinking keep dementia at bay?

While drinking alcohol in excess is associated with many health hazards, new research has found that older adults who consume alcohol moderately on a regular basis are more likely to live to the age of 85 without dementia or other cognitive impairments than non-drinkers.

"This study is unique because we considered men and women's cognitive health at late age and found that alcohol consumption is not only associated with reduced mortality, but with greater chances of remaining cognitively healthy into older age," said senior author Linda McEvoy, Associate Professor at University of California San Diego School of Medicine.

In particular, the findings published in the Journal of Alzheimer's Disease showed that among men and women 85 and older, individuals who consumed "moderate to heavy" amounts of alcohol five to seven days a week were twice as likely to be cognitively healthy than non-drinkers.

Cognitive health was assessed every four years over the course of the 29-year study, using a standard dementia screening test known as the Mini Mental State Examination.

Drinking was categorised as moderate, heavy or excessive using gender and age-specific guidelines established by the National Institute on Alcohol Abuse and Alcoholism, part of US National Institutes of Health (NIH).

By its definition, moderate drinking involves consuming up to one alcoholic beverage a day for adult women of any age and men aged 65 and older; and up to two drinks a day for adult men under age 65.

Heavy drinking is defined as up to three alcoholic beverages per day for women of any adult age and men 65 and older; and four drinks a day for adult men under 65.

Drinking more than these amounts is categorised as excessive.

"It is important to point out that there were very few individuals in our study who drank to excess, so our study does not show how excessive or binge-type drinking may affect longevity and cognitive health in aging," McEvoy said.

Long-term excessive alcohol intake is known to cause alcohol-related dementia.

For the study, the researchers followed 1,344 older adults - 728 women and 616 men - for 29 years.

The researchers pointed out that the study is not a recommendation for everyone to drink.

"Some people have health problems that are made worse by alcohol, and others cannot limit their drinking to only a glass or two per day. For these people, drinking can have negative consequences," lead author Erin Richard from University of California San Diego said.