For many years, researchers believed red wine might be a magical elixir. This notion dated back to the 1990s and what's known as the "French paradox" — the observation that the French drank lots of wine and had lower rates of cardiovascular disease.
We now know this is likely wrong. Scientists have since discovered that drinking very small amounts of any type of alcohol — no more than one drink a day for women, two for men — may have some modest health and heart benefits. There's nothing special about red wine on this score. It could be white wine, or beer, or whiskey.
This week, the Annals of Internal Medicine published a new study on this question, and it mostly jibes with this understanding. The researchers recruited 224 patients — who all had Type 2 diabetes and did not drink alcohol before enrolling in the trial — and randomly assigned them to three groups: They had to drink 5 ounces of either red wine, white wine, or mineral water every night with their dinner for two years. They were also given instructions to follow a Mediterranean diet with no calorie restriction.
After two years, the researchers found that the wine drinkers seemed to have better health outcomes than those who had just stuck to water. The red wine drinkers had slightly better results, although the effect wasn't huge.
In particular, both red and white wine drinkers did better on glucose control tests, and the red wine drinkers also saw improvements in their HDL (or "good") cholesterol (an increase of 0.05 mmol/L). So, the study suggests, a bit of wine every day seemed to be linked with better lipid and glucose control compared with just water.
Past research has found benefits from alcohol — not just wine per se
Now, there are a few important limitations on this latest study. It involved only adults with Type 2 diabetes. This also wasn't a "blind" study —participants knew what they were drinking, which might have biased the outcomes.
What's more, the researchers studied wine only, without comparing the effects of other types of alcohol. That's a key omission, because other research seems to suggest a moderate amount of any type of alcohol has benefits for the heart, blood lipid levels, and longevity.
In short-term studies, where scientists measure physiological effects in people who drink moderately, alcohol generally seems to raise the amount of HDL (or good) cholesterol in the blood and decrease clotting, essentially acting as a blood thinner. Again, this seems to be as true of beer or liquor as of red or white wine.
Meanwhile, in long-term observational studies that compare drinkers and non-drinkers, these findings translate pretty definitively to better health outcomes for the light to moderate drinkers. Overwhelmingly, they had lower rates of heart disease and heart attacks and longer lives. Moderate drinkers also had lower rates of diabetes, another important risk factor for heart disease (although this result is less definitive).
So researchers have come to believe that wine, even red wine, probably has no extra health benefits above and beyond those that come from drinking a moderate amount of alcohol, period.
That said, any potential benefit from drinking needs to be weighed against the risks: Too much alcohol can increase the risk of premature death and cause a host of other medical problems. And researchers find that all the health benefits come from very moderate intake — up to one serving a day for women and two for men. (See the chart above for a breakdown of what one serving looks like.) Anything more, and that benefit disappears.
To learn more about what we know and don't know about red wine, see our Show Me the Evidence review.