Of course I would like to believe the scientists who claim that eating dark chocolate positively affects our wellbeing and that drinking moderate amounts of red wine improve our health. I like both dark chocolate and red wine and sometimes together to get a double wellness whammy. What’s not to like?
Question is are the scientists actually right? We have written numerous posts about claimed superfoods doing wonders to our health when it is actually the overall diet that is most important, not the individual components as such. Sure we have also fallen into the trap of praising some individual foods as the popular press did this time for fashionable dark chocolate and red wine. Even scientists want to get some attention.
Dark chocolate and health
Let’s start with reviewing the dark chocolate findings. Scientists from the University College London, the University of Calgary and Alberta Health Services Canada assessed data from 13,626 adults from the US National Health and Nutrition Examination Survey. Daily chocolate consumption and type of chocolate was assessed against scores on the Patient Health Questionnaire, which assesses depressive symptoms.
As usual, a range of other factors including height, weight, marital status, ethnicity, education, household income, physical activity, smoking and chronic health problems were taken into account to ensure the study only measured chocolate’s effect on depressive symptoms. Overall, 11.1% of the population reported any chocolate consumption, with 1.4% reporting dark chocolate consumption.
The scientists found that eating dark chocolate positively affected mood and relieved depressive symptoms. As a matter of fact, individuals eating any amount of dark chocolate had 70% lower odds of reporting clinically relevant depressive symptoms than those who reported not eating chocolate at all.
So far so good!
To be believable it is important to find a biological mechanism that can explain the results. And there are several. Chocolate contains a number of psychoactive ingredients which produce a feeling of euphoria and phenylethylamine which is believed to be important for regulating people’s moods. Also, dark chocolate in particular has a higher concentration of flavonoids, antioxidant polyphenols that have been shown to improve inflammation and play a role in the onset of depression.
Another strength of the study is that daily chocolate consumption was derived from two 24‐hour dietary recalls and not from much more dubious food frequency questionnaires that are so common.
And the bad!
Although the study included a large overall sample, there were less than 200 individuals that reported dark chocolate consumption. There could also be other confounding factors not taken into account.
There is some caution expressed by the scientists themselves claiming that further research is required to clarify causation. It could be the case that depression causes people to lose their interest in eating chocolate, or there could be other factors that make people both less likely to eat dark chocolate and to be depressed.
What about red wine and health?
Scientists at King’s College, London have reported that red wine consumption could be linked to better gut health. The study included a group of 916 female twins and tested the effects of consuming beer, cider, red wine, white wine and spirits on the gut microbiome, the micro-organisms found in the digestive tract.
And compared to other alcoholic drinks they found that the gut microbiome of red wine drinkers was more diverse – a sign of better gut health. The researchers speculated that the positive effect of red wine could be due to its higher amount of chemicals called polyphenols that act as antioxidants.
So what to say!
Well, this could be a big thing.
We know that our gut microbiota can affect multiple aspects of our general health and play a role in many illnesses. As a matter of fact, gut microbes are responsible for producing thousands of chemical metabolites affecting our overall metabolism, our immune system and our brain.
We have long known of the unexplained benefits of red wine on heart health. The study findings that moderate red wine consumption is associated with greater diversity and a healthier gut microbiome could at least partly explain its beneficial effects on heart health.
And there is more
As a check on possible genetic or family biases, the scientists found that the twin who drank red wine more often than the related twin had a more diverse gut flora. White wine drinkers who should be socially and culturally similar, had no significant differences in diversity.
Also, in further support of the findings they were shown to be consistent with results from two other studies of similar size in the US (the American Gut project) and Belgium (Flemish Gut Project) basing the conclusions on a total of about 3000 twins.
And in a previous experimental Spanish study from 2012, admittedly involving only ten healthy middle-aged males, the volunteers were given one of three different beverages to drink each day in each of three 20-day periods: normal strength red wine, low alcoholic red wine and gin. Drinking any type of red wine resulted in a larger percent of certain beneficial gut bacteria, but consuming gin had no effect on the gut flora.
So all good?
Not so fast.
Note that again the main study was observational and not experimental and the previous experimental study was very small. The study subjects in the observational study self-reported their food and drink intake with the usual associated bias. The scientists then prospectively tried to statistically link the reported alcoholic drink consumption with test results from the gut microbial analysis. Using twins strengthens the findings but doesn’t conclusively show causality.
There are the usual professional warning that the positives should still be weighed up against the negative impacts of alcohol. Any potential benefits of red wine polyphenols should be considered alongside alcohol’s links to over 200 health conditions, including heart disease and cancers.
But the beneficial effects were achieved by a very moderate glass of red wine a week or even a fortnight.
The moral of the story
If you’re going to eat chocolate pick the dark variety and you will not only have an enjoyable time but you might also be happier.
And the same goes for alcohol consumption. Drink in moderation and pick red wine and the resulting happiness might also be associated with improved health.
Also remember that the beneficial polyphenols found in dark chocolate and red wine can also be found in a range of other foods.