About to uncork that bottle of merlot? A study finds that moderate drinking may decrease the risk of dementia and cognitive decline in older people.
Researchers analyzed 143 studies that looked at the association between moderate alcohol consumption and mental abilities. The meta-analysis, published this month in the journal Neuropsychiatric Disease and Treatment, looked at research dating back to 1977.
Studies done between 1977 and 1997 mostly focused on younger people ages 18 to 54 and for the most part sought to determine whether moderate drinking had any damaging effects; Overall it didn't, said Michael Collins, the study's co-author and professor in the department of molecular pharmacology and therapeutics at Loyola University Chicago, Stritch School of Medicine.
Later studies from 1998 to the present focused more on mental status tests examining memory and cognitive function among mostly older people, he added, and most showed that drinking moderate levels of alcohol showed no effect or a decreased risk of dementia and cognitive impairment compared to control groups.
Among the studies surveyed, researchers found that this link was seen in 14 out of 19 countries, including the U.S.
Overall, those who drank moderately were 23% less apt to acquire dementia or other forms of Alzheimer's disease, or to develop some cognitive damage.
Heavy drinking, on the other hand, was linked with slightly higher risk of dementia and cognitive impairment that was not statistically significant. Heavy drinking was defined as having more than three to five drinks a day, and moderate drinking as one drink a day for women, two for men.
Both men and women seemed to benefit from moderate drinking even though the study authors noted that the sexes have different drinking patterns: Men tend to drink more than women, and overall they prefer beer and spirits, while women edge toward wine.
When it came to determining which types of alcohol were best, the jury may still be out Some studies showed that wine had a slight edge over spirits, but most studies didn't differentiate among various types of alcohol, and others that did found no differences among the different types.
Collins said that since most of the studies analyzed were epidemiological, few reasons were offered as to why alcohol might be beneficial for brain function. Among the theories, he said, is that low to moderate levels of alcohol may have anti-inflammatory properties.
"There's a lot of feeling that brain inflammation is involved in Alzeimer's disease," he said. "If alcohol is increasing molecules that are suppressing inflammation in other tissues, then it probably also does that in the brain."
Drinking alcohol also has been shown to raise levels of HDL "good" cholesterol; That in turn could increase blood flow to the brain, making the brain healthier.
Most health professionals say that people who don't drink shouldn't start, and there may be other ways to protect against cognitive problems and dementia via lifestyle. "We're not qualified to say," Collins added, "but there are some studies out there that say a Mediterranean diet and moderate exercise may be better for you in terms of cognitive decline."
But, he warns: "Alcohol is a double-edge sword. For many people it is a dangerous problem worldwide and one of the major causes of mortality. But there is this side that should be taken into consideration."