One of the most feared disabilities of aging is dementia , which often begins with memory loss but may end with troubling changes in personality and behavior. Alzheimer’s disease is the most common form of dementia, followed by vascular dementia , caused by a series of small strokes. Atherosclerosis , a buildup of fatty deposits in the arteries, appears to be a risk factor for both.

Moderate alcohol consumption by older adults has been shown to reduce their risk of cardiovascular disease, in which atherosclerosis is known to play an important role. It stands to reason, then, that moderate alcohol consumption might also reduce the risk of dementia in older adults. But the results of studies examining such a relationship have been mixed.

In a study published in the March 19, 2003 Journal of the American Medical Association , researchers reported that older adults who consumed moderate amounts of alcohol (between one and six drinks per week) were significantly less likely to develop dementia than those who did not drink or who drank heavily.

About the Study

The study subjects were selected from participants in the Cardiovascular Health Study (CHS), which began in 1988. The CHS comprised a group of 5888 men and women aged 65 and older. Upon entering the study, all participants filled out medical history questionnaires, and underwent a physical examination and laboratory testing. They also completed the Mini-Mental State Examination (MMSE), a measure of cognitive functioning.

All CHS participants have had yearly exams during which they answered questions about the number and frequency of alcoholic beverages they consumed. One serving of alcohol was defined as 12 ounces of beer, six ounces of wine, or one ounce of liquor.

Between 1992 and 1994, CHS participants underwent magnetic resonance imaging (MRI) testing of the brain. They also completed various cognitive tests, including a follow-up modified MMSE.

Based on the MRI and cognitive test results, researchers identified and selected 373 subjects with dementia and 373 subjects without dementia (controls) for the present study. For each participant, the researchers averaged their alcohol consumption at the beginning of the study with their alcohol consumption recorded closest to the date of their MRI examination.

The Findings

Of the 373 patients with dementia, 258 had Alzheimer’s disease alone, 44 had vascular dementia alone, 54 had both Alzheimer’s disease and vascular dementia, and 17 had other types of dementia.

The researchers found that compared to abstainers who had never consumed alcohol:

  • Study subjects who drank 1–6 alcoholic beverages per week had a 54% lower risk of dementia
  • Men and women who drank less than one alcoholic beverage per week had a 35% reduced risk of dementia
  • Those who drank between 7–13 alcoholic drinks per week had a 31% reduced risk of dementia
  • Participants who drank 14 or more drinks per week had a 22% increased risk of dementia

These findings held true even after controlling for several factors that are known to affect the risk of dementia including age, sex, race, apoE4 status (a genetic risk factor for dementia), use of estrogen replacement therapy, and smoking status.

The relationship between alcohol consumption and dementia was similar for Alzheimer’s disease and vascular dementia.

How Does This Affect You?

This study found that adults over the age of 65 who consumed up to 13 alcoholic beverages per week had a lower risk of dementia than nondrinkers and heavier drinkers. One to six drinks per week seemed to confer the greatest benefit.

If you already drink alcohol, these findings suggest that your risk of dementia may be lowered if you consume no more than one or two drinks per day. However, if you don’t drink, don’t start. This was an observational study, which means it is not possible to conclude that the alcohol itself was beneficial. It may have been some other unknown factor not accounted for by the researchers. Besides, heavier alcohol consumption has many risks including death from cancer, motor vehicle accidents, and liver disease.

Because the study was conducted on participants aged 65 and older, these findings do not necessarily apply to younger populations.