Red wine, an ally of microbiota? Researchers at King's College London have compared the effects of red wine on intestinal flora with those of other alcohols. And they think they have isolated a positive impact, according to their study published this Wednesday in the journal Gastroenterology.
The scientists studied 916 twin women, including their reported consumption of beer, wine, cider and spirits. They wanted to determine possible differences in the diversity of gastrointestinal microbes (the microbiota), whose balance is crucial for the body. As a result, bacterial diversity was better for women who consumed relatively more red wine, while no positive association was found among other types of alcohol drinkers. A minor effect has been observed with white wine.
An imperfect study
"The greater the diversity, the better it is for us to prevent disease and better metabolize food," says the main author, Caroline Le Roy. An imbalance between good and bad germs can in turn affect the immune system or be associated with weight gain or increased cholesterol.
But this type of study is far from perfect. First because correlation does not mean causality. It is possible that other factors invisible to researchers have affected the microbiota of wine drinkers. Their good intestinal flora may be due to other behavior or other ingredients not taken into account by the study. It is also almost impossible to measure the totality of what an individual eats and drinks. This still limits studies that claim to have an effect on the health of a single ingredient or type of diet.
Alcohol is bad for your health
That said, the researchers tried to strengthen their results by confirming them in two additional groups, a thousand participants in the United States and the Netherlands, as well as in another group of British twins. The advantage of studying twins is that any differences observed are probably related to their environment, since they are genetically identical.
However, this study should not be interpreted as a call to drink wine. "You do not have to drink red wine, and you do not have to start drinking it if you do not drink," says Caroline Le Roy. Drinking alcohol is generally bad for your health: its consumption is linked to 200 diseases, including mental problems, cardiovascular diseases and cirrhosis.