A handful of studies have shown that people who drink one or two glasses of wine per day generally live longer than people who do not drink or who drink beer. Does wine really increase longevity? An article on the Medpage Today website suggests that Eating Well May Explain Wine Drinkers’ Better Health.
Prior studies most likely suffered from a phenomenon with which economists know intimately: Selection Bias.
Wine is generally an “upper class” drink while beer is thought to be a “lower class” drink. Thus, people who drink wine are on average better educated, have more income, and eat healthier food. These three factors have been shown to be highly correlated with longevity. From the prior studies we conclude that well-educated, affluent individuals who eat healthy live longer and also happen to drink more wine; wine is not the cause of their added longevity.
As for me, I’ll stick with a good Belgian beer such as Chimay or Leffe over a glass of Merlot any day.