Researchers recently published work that was widely publicised as showing the MIND diet to be protective against dementia. Its a version of the Mediterranean diet, but with some extra restrictions - less variety of fruits included and with an emphasis on reducing salt intake. The Mediterranean diet often gets good coverage as it should - without giving my own advice a diet label, it is exactly they style of eating I recommend in all my books.
The Nordic diet and the Okinawan originate in countries far from the Mediterranean, where olives, olive oil and the variety of vegetables on offer in countries surrounding the Mediterranean Sea are not on hand. Yet, they rightly claim similar body and brain benefits.
So who is right? Eat lots of cold water fish and few grains as in the Nordic, or splash the olive oil over a platter of seasonal veggies as in the MIND and Mediterranean?
The answer is that both, or all, are.
All these high profile diets have something in common - food is predominantly seasonal, locally sourced and fresh (or at least minimally processed - pretty much only for preservation), and they all contain foods offering good oils - from olives, nuts, seeds and/or oily fish. That is exactly what the science I cover in Better Brain Food suggests helps your brain.
The problem with research in nutrition is that its virtually impossible to 'blind' people to what is being investigated.
Let me explain that - the gold standard in scientific research methodology is using a 'double blinded, randomised controlled study' - stay with me, I promise it will become clearer! In these studies participants are randomly divided into separate groups - some are given the 'intervention' (that's the thing being tested) and some are given no intervention (called the control group), but neither the researchers or the participant, knows whether they are in the intervention or the control group (double blinded). That sort of trial is fairly easy if you are looking at the effect of a medication or individual nutrient because tablets can be made that look exactly the same but contain completely different contents. So, its impossible to tell, when taking the tablets, if they contain the substance being tested or not.
Its important to be able to 'blind' people to which group they are in because we are human, and when people know what they are taking they can behave in a way that they believe is associated with whatever is being tested. And the control is essential because it helps remove the chance that things are happening due to something completely unrelated to what is being tested.
But this is not really possible when testing nutritional interventions because we know if we are eating meat, or oranges, or lentils or pizza........double blinding and controlling is virtually impossible.
So researchers rely on observational studies mostly - often getting people to record what they eat and seeing what happens or has happened, over time. Now that introduces another dilemma - its been proven time and again that people tend to under-report eating foods they think of as 'bad' and conversely increase their reporting of the 'good' things. It can be hard to know exactly whats been eaten.
Also, people who eat more 'healthily' are more likely to be the ones who are not smoking, who exercise regularly, stay engaged in society and learn new things and who get check ups to help prevent later illness - so is it their diet, or the exercise or something else that leaves them with better brain health or helps them live longer?? Its very difficult to know, maybe impossible.
So.....I'm not saying for a moment that these diets are bad at all - they are great! Its just that none offer the whole answer.
My books, Eat To Cheat Ageing, Eat To Cheat Dementia and Better Brain Food all offer sensible, practical advice for the everyday person, based in these diets and much more.
Eat local, seasonal, fresh food as much as possible with plenty of variety of vegetables and fruits. Support your gut health with fibrous and fermented foods and get good oils from nuts, seeds and oily fish