The study entitled “Alcohol Intake and Cognitively Healthy Longevity in Community-Dwelling Adults: The Rancho Bernardo Study” surveyed 1,344 older adults from Rancho Bernardo in San Diego, California. Participants included were 728 caucasian women and 616 caucasian men with some college education. The study was conducted over a span of 29 years from 1984 to 2013, led by senior author Dr. Linda McEvoy, an associate professor at the University of California San Diego School of Medicine and lead author Erin Richard, a graduate student at the Joint San Diego State University / University of California San Diego Doctoral Program in Public Health. The findings of this study was published in the August issue of the Journal of Alzheimer's Disease.
Previous studies have reported a correlation between moderate alcohol intake and longevity, but this study is unique because considerations have been made for cognitive health at late ages. The researchers found that moderate alcohol consumption is associated with a significant reduction in mortality and greater chances of remaining cognitively healthy as the aging process takes place. Findings show that men and women over the age of 85 who had a history of moderate to heavy consumption of alcohol five to seven days a week were more likely to be cognitively healthy than non-drinkers. The participants' cognitive health was assessed every four years using a standard dementia screening test called the “Mini Mental State Examination”. This research was funded by the National Institutes of Health (NIH).
The National Institute on Alcohol Abuse and Alcoholism establishes the categories of alcohol consumption as the following: Moderate consumption involves one alcoholic beverage per day (adult women of any age and men over 65) and two drinks per day for adult men below 65; heavy consumption involves three alcoholic beverages per day (adult women of any age and men over 65) and 4 drinks a day for adult men below 65; and more than these amounts were categorized as excessive. According to the study, only a few individuals were categorized as excessive drinkers.
A number of studies have already proven that long-term excessive alcohol consumption causes alcohol-related dementia and other chronic diseases. There have been many studies of alcohol as a detriment to overall health (physical and mental), which is why the study is a hot topic for debate – whether alcohol intake positively or negatively affects lifespan and cognitive health.
Aside from behaviors and health outcomes, demographic factors were also considered in the study: higher socioeconomic quintiles, including the middle class to upper middle class, were associated with lower risk behaviors (e.g. smoking), lower mental illness rates, and better access to health care. Individuals from lower quintiles are more inclined towards the opposite of the description above. However, the study is also limited by removing confounding variables such as smoking and obesity.
While the study states that moderate drinking may be part of a healthy lifestyle, it is not a recommendation for everyone to drink. Individuals experiencing health problems and chronic diseases are worsened by alcohol consumption, and may have the chance of shortening the individual's life span. Some individuals are more prone than others, especially if they have uncontrollable drinking habits, or history of alcoholism.