The University of Glasgow research suggests low to moderate alcohol intake improves the performance of the female brain while protecting against cognitive decline.The fact that spirits, beer and wine all show the same effect argues that it's the ethanol in them, rather than any other substance, that's the active ingredient.
Almost 6,000 people aged 70 to 82 took part in the study, carried out in Ireland, Scotland and the Netherlands.
Little difference was found between male drinkers and non-drinkers, but women who consumed between one and seven units a week scored significantly better than teetotal females.
“Differences were seen across all cognitive domains, including global cognition, speed of information processing and verbal memory,” said David Stott, author of the study and professor of geriatric medicine at the university.
Researchers found women who drank at least three units of alcohol per week scored consistently better than non-drinkers.
In addition to improving mental performance, Stott found alcohol consumption appeared to protect women from the age-associated cognitive decline that can lead to dementia — benefits that were not seen in the men studied.
One reason may be that men drink more than recommended in the guidelines, negating any positive effects. While previous studies have said wine in particular has protective qualities, Stott said spirits and beer also improve mental performance.
Or is it? Correlation doesn't imply causation - maybe there's another factor, something that leads women with greater cognitive ability to consume moderate amounts of alcohol.
And why the sex difference? Perhaps the men are "irresponsible" and exceed the recommended amounts. Perhaps. But maybe that's just sexism, it sounds very much like the mirror-image of some of the calumnies spread about women in days gone past.
And if there's one thing I've learnt about biology, it's just how fuzzy these bimodal distributions are. Even if 99% are either in category A or category B, there's always some in both A and B, and some in neither. I'd be interested to see if there was any overlap, and how large the differences were.
But let's assume everything is as it appears. That alcohol affects the brains of men and women differently, all other things being equal. Ok then.... why? How?
It won't surprise long-time readers of this blog that male and female brains differ in a number of respects. From gross differences like brain weight, medium ones such as number of cells in particular structures, right down to differences in response to neurotransmitters and hormones at the cellular level, there are objectively measurable differences that we know have gross effects. For example, the propensity of women to be more subject to depression than men.
I don't have the knowledge to even guess why the effects are different, whether it's an effect of communications between cells and structures, or an effect at the cellular level. I suspect that neither do the researchers, "more work needed".
It would be interesting though if the samples included comparable numbers of transsexuals, both male and female. We know that "male transsexuals have male brains" over-simplifies matters. In some very important, even crucial, ways they definitely do. But other structures may not be so clear-cut male. And vice-versa for the women too. It would be great to include some intersexed people as well, of both sexes, with each of a variety of common intersex conditions. We - people like me - could be useful tools to help prize out some of Nature's more intractable secrets.
Of course I'm talking like a Scientist and a Geek. I'm sure that many who would make wonderful experimental subjects wouldn't feel happy at being "Laboratory Animals". To me though, being my own experimental animal is wonderful, I feel I'm making a real contribution to Human Knowledge. No ethical issues about informed consent either, I know exactly what I'm getting into.
I don't expect others to share my views though. And though I speak with the tongues of Men and Angels, I may not be able to share my constant wonder at this bizarre, baroque, and ultimately beautiful Universe that we live in.
Science, although it strives for objectivity, is ultimately a very Human pursuit. It speaks to our inner children, curious and unafraid. And able to find wonder in the search for the Higgs Boson, or Measuring the Marigolds, or even figuring out why drink appears to make women think better.
On that note, I might just have a small glass of Green Ginger Wine tonight.