A review of previous research suggests that dementia may be prevented by consumption of moderate amounts of alcohol. The study, published in Neuropsychiatric Disease and Treatment reviewed 143 studies involving more than 365,000 participants in 19 countries.
They found that moderate drinking--one drink a day for women, two drinks a day for men--reduced the chances of developing dementia or Alzheimer's by 23%. The study saw some suggestion that heavy drinking--more than three to five drinks a day--increased the risk of dementia, but that finding was not statistically significant.
Wine seemed to be somewhat better than other forms of alcohol, but there weren't enough studies for the researchers to definitely recommend it over other types of alcohol.
The study was criticized by some doctors because it was an epidemiological study. In other words, it looked at a large population of people and tried to find what people had in common (no dementia and moderate alcohol consumption). While these types of studies can show areas for further research, it can be difficult to draw firm recommendations from them.
The gold standard of research is a clinical trial, where patients are assigned one treatment or another and their progress is followed.
