Red wine could be good for the gut, according to researchers. The benefits are likely to come from polyphenols – compounds that white wine, beer and cider have far less of, the King’s College London team says.
A glass a fortnight was enough to make a difference, but researchers say the findings are not an excuse to binge.
Polyphenols are also found in many fruits and vegetables.
Polyphenols, such as resveratrol in the skin of red grapes, are micronutrients that are thought to have beneficial properties and act as a fuel for useful microbes living inside our bowel.
Our guts contain trillions of bacteria and other micro-organisms and this community of “friendly” bugs helps keep us healthy.
A growing body of research suggests small changes to our microbiota can make us more susceptible to illnesses such as Irritable Bowel Syndrome, heart disease and obesity and may even affect our mood and mental health.
Our diets, lifestyles and some types of medication that we may take can upset this finely balanced gut ecosystem.
The study, published in the journal Gastroenterology, looked at thousands of people living in the UK, the US and the Netherlands.
The participants – all twins enrolled in health research programmes – were asked about their diet and how much and what type of alcohol they typically drank.
The gut microbiota of red wine drinkers was more diverse than that of non-red wine drinkers.
Gut bug diversity increased the more red wine a person consumed, although occasional drinking – one glass a week or fortnight – appeared to be sufficient.
None of the participants was a heavy drinker.
The researchers say heavy consumption is not recommended and would probably have a bad effect on gut bugs, as well as on a person’s general health.
Researcher Dr Caroline Le Roy said: “This is an observational study so we cannot prove that the effect we see is caused by red wine.”
“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.
“You do not need to drink every day and it is still advised to consume alcohol with moderation.”
She said she would like to do a follow-up study offering people red wine, no alcohol or red grape juice to see what effect each has on gut microbiota.
“We are starting to know more and more about gut bacteria. It is complex, and we need more research, but we know that the more diversity there is, the better it appears to be for our health.”