Start with a curry, followed by chocolate with red wine and tea. Toss in some grilled vegetables with olive oil (Mediterranean diet) and a Nintendo DS, to be played with not eaten of course, and you will be practically dementia-proof. OK, maybe not, but the chances of you developing Alzheimer’s will be significantly reduced…won’t they?

‘Foodstuff prevents dementia’ seems to have become a genre of epidemiological study and a new one pops up with a press-release every few weeks. I’ve just noticed this one on the BBC Health website, ‘Vitamin D is mental health aid‘, so it may be time to head for the sun or failing that, gorge yourself on some fatty fish. You can take a look at the abstract here and - surprise, surprise - the usual flaws are present. Firstly, it’s a cross-sectional study, so they have found an association but causation doesn’t come into it. And were they looking at dementia? No, the survey included the Abbreviated Mental Test Score which is a 10 point screening, and not diagnostic, tool for cognitive impairment. To be fair to the researchers, they do point out these limitations (along with several others) in their paper but it always seems to get lost in translation. And just to make sure you don’t miss the dementia link, these articles never appear without a spokesperson from an Alzheimer’s charity calling for more research.

I do wonder where these epidemiologists get their research ideas from: trawling the local supermarket? Of course there is only one sure-fire way to avoid dementia, as The Who memorably sang…and no, it wasn’t ginkgo biloba.