Alcohol and Gut Health
The Microbiome
The microbiome (a collection of microorganisms in the gut) plays a broad role in human health, affecting such diverse areas as bodyweight, immunity, mood, and mental functions. And a lack of “good” bacteria, or an overgrowth of “bad” bacteria, can lead to a variety of health problems. Therefore, it is no surprise that a gut microbiome with a greater number of different bacterial species, is considered a benchmark of good health.
Given the prevalence of current research on the microbiome, it was only a matter of time until someone had a look at how alcohol affects this most important area of the body. And, now researchers from Kings College in London have published a study (in the journal, Gastroenterology; Aug/2019) examining the effects of a variety of alcoholic beverages on the gut microbiome.
In a group of just over 900 female twins (from the UK), they analyzed the effect of beer, cider, red wine, white wine, and spirits, on the gut microbiome, and general health.
And the Winner is…
Results indicated the only beverage which led to a diverse gut microbiome was red wine: the gut microbiota of red wine consumers contained both more good bacteria, and far more different bacterial species, than non-consumers. This improved quantity, and variety, of good bacteria was not observed among those who drank beer, white wine, or spirits.
(This study also found red wine consumption was associated with lower levels of obesity, and ‘bad’ cholesterol, which was in part due to the gut microbiota.)
One author of the study, Dr Caroline Le Roy said: “While we have long known of the unexplained benefits of red wine on heart health, this study shows that moderate red wine consumption is associated with greater diversity and a healthier gut microbiota that partly explain its long debated beneficial effects on health.”
Why Red Wine?
This study went further and also examined three different groups, studied in the UK, the U.S., and Belgium. And, this time, they also allowed for other factors that might influence gut status, including age, weight, and the regular diets, and socioeconomic status of the participants. Again, the results were the same, showing the benefits of red wine for gut health.
Why does red wine do so much to support the microbiome? Well, the researchers believe the benefits of red wine, in this case, are due to the high amount of polyphenols it contains. Polyphenols are protective chemicals, found in many fruits and vegetables, with well proven, powerful antioxidant properties, which now, it seems, also act as food for the microbes in our gut.
Lead author Professor Tim Spector said: “This is one of the largest ever studies to explore the effects of red wine in the guts of nearly three thousand people in three different countries and provides insights that the high levels of polyphenols in the grape skin could be responsible for much of the controversial health benefits when used in moderation.” (Study)
This polyphenol thesis is backed up by an earlier study from Australia (2018). These researchers concluded that: “Intake of polyphenols derived from grape and red wine can modulate gut microbiota and contribute to beneficial microbial ecology that can enhance human health benefits.” (Study)
How Much Red Wine?
“Although we observed an association between red wine consumption and the gut microbiota diversity, drinking red wine rarely, such as once every two weeks, seems to be enough to observe an effect. If you must choose one alcoholic drink today, red wine is the one to pick as it seems to potentially exert a beneficial effect on you and your gut microbes, which in turn may also help weight and risk of heart disease. However, it is still advised to consume alcohol with moderation,” added Dr Le Roy.
At this point I will add a caveat. I did a detailed analysis of red wine, and the broad benefits for general health, and longevity, coming to the conclusion that, it is a very good idea to drink organic red wine, whenever possible (especially if you are drinking it frequently).
For more details about red wine, and current farming practices, have a read of my blog “Wine for Health”.
For the Non-Drinker As you might have noticed, the briefly mentioned Australian study, which confirms the value of polyphenols for gut health, mentioned “grape and red wine”. In my research, detailed in the “Wine for Health” blog, I discovered the only beverage with the same overall benefits as red wine was concord grape juice. Thus we can assume that, for those who choose not to drink alcoholic beverages, organic concord grape juice is a viable option.