Glass of Wine a Day May Ward Off Depression
But, moderate drinking might also just be sign of normal social life, researchers add
"An adequate social life is the most important factor we know that protects people from depression," Tang said. "Perhaps not drinking is a sign of serious social isolation in Spain while drinking a glass of wine a day is simply a sign of having a normal social life."
For the study, researchers followed more than 5,500 light-to-moderate drinkers for up to seven years. All the participants were part of a large Spanish study on nutrition and cardiovascular health, and were between 55 and 80 years old.
None of the individuals had suffered from depression or had alcohol-related problems at the start of the study. Over seven years, with medical exams, interviews with dietitians and questionnaires, the researchers kept tabs on participants' mental health and lifestyle.
Wine was the most popular drink and participants who drank two to seven glasses a week were the least likely to suffer from depression, compared to nondrinkers.
These findings remained significant even after the researchers took factors such as smoking, diet and marriage into account.
Eva Redei, a distinguished professor in the department of psychiatry and behavioral sciences at the Feinberg School of Medicine at Northwestern University, in Chicago, also expressed doubts about the direct effect of wine on depression.
"Considering the increase of major depression in the age group examined in this study, the finding of protective effects of moderate alcohol consumption is intriguing," she said.
However, it raises more questions than answers. "Is moderate wine consumption related to increased socialization, decreased cardiovascular events, or as it seems, increased activity? These questions are not answered by this study, but the findings are definitely worth noticing," Redei said.
"Is it possible that 'in vino veritas' [in wine there's truth] reflects a bigger truth?" she asked.