As a nutritionist, perhaps I’m more acutely aware than most of the often overblown claims made for ‘brain boosting’ foods and supplements. Take oily fish: fantastic, tasty, super-healthy, it almost goes without saying. But browse online and you’ll find no end of articles claiming that eating salmon, mackerel and sardines helps ‘support brain function’ amid other claims.
Sounds great. Problem is, there’s no good evidence for it. In fact, last year a study of more than 8,000 adults revealed that the amount of oily fish consumed throughout a person’s lifetime made no difference to their chances of developing dementia.
Blueberries, dark chocolate and even coffee are also often cited without any real evidence. Don’t even get me started on goji berries.
The truth is, there’s no one magic nutritional bullet, or way to ‘eat to beat’ dementia. It’s just not that simple – and I only wish it were.
Popular in countries such as Greece, Spain and Italy, the Mediterranean diet includes small amounts of non-fatty meat, poultry and fish, along with wholegrains and unsaturated fats
Scientists are investigating whether Fitbits, phones and smart watches could soon be used to pick up subtle signs of dementia years before symptoms show.
It is currently diagnosed using memory tests and brain scans, but only once symptoms have appeared. Also, many trials of treatments fail because they are tested on people whose disease is too far advanced, after they have suffered significant damage to their brain. Experts hope by picking it up earlier, measures could be taken to prevent decline.
Researchers are now testing whether the gadgets could be used to analyse the owner’s behaviour, such as their sleep and speech patterns and walking gait, and that if certain things start to change in tiny ways the user could not possibly notice themselves it may be a sign they are at risk of developing dementia.
The landmark study, called Early Detection of Neurodegenerative Diseases (EDoN), will analyse these normally imperceptible changes – such as how quickly people type text messages and emails – among those who then go on to develop dementia.
Professor Carol Routledge, director of research at Alzheimer’s Research UK, who is spearheading the project, said: ‘The stage you want to detect these diseases is ten or even 20 years earlier than we do today, before it’s too late. If we could, with these new and emerging technologies, we could intervene with lifestyle advice, or therapeutic drugs.’
Last week, a major study suggested a blood test could be used to spot Alzheimer’s, the most common type of dementia, years before symptoms start. The test looks for traces of tell-tale proteins in the blood that might indicate a person is at risk.
That’s not to say, however, that diet doesn’t play an integral role in brain health. As we’ve learned, metabolic diseases – such as heart disease and diabetes – are responsible for the lion’s share of dementia cases in the UK. It’s hardly surprising, then, that diets proven in multiple scientific studies to reduce the risk of such conditions, also benefit the brain.
We’re talking about the Mediterranean diet – long recognised to halt the development of heart disease, diabetes, high blood pressure and, also, dementia.
Popular in countries such as Greece, Spain and Italy, it includes small amounts of non-fatty meat, poultry and fish, along with wholegrains like brown rice and wholemeal bread and unsaturated fats like nuts and olive oil, and plenty of fruit and veg.
Studies have found the rates of dementia in participants who ate this way are up to 40 per cent lower than those who do not.
Interestingly, eating this way seems to have more impact on brain health than a traditional weight-loss diet. A ground-breaking study from 2013 – the Predimed study – found that overweight individuals prescribed a Mediterranean diet that included olive oil and nuts every day for six years were less likely to develop dementia than those on low-fat plans.
And Swedish research involving more than 2,000 healthy over-60s found that sticking to this type of diet was linked to a slower rate of cognitive decline and thinking skills.
Some scientists believe the healthy fats abundant in the Mediterranean diet, found in nuts, fish, olive oil and some meat, may reduce the inflammatory molecules in the brain that affect our ability to process information.
But the simple fact is that eating lots of veg, fruit, wholegrains and lean protein fills you up, helping portion control and reducing the risk of obesity, which is one of the biggest risk factors for poor heart health, diabetes and, therefore, dementia.
High blood pressure is another leading trigger of dementia – it damages the tiny blood vessels that provide oxygen to the brain.
One in four Britons suffer from it and according to Government figures, 80 per cent of cases are caused by lifestyle habits, including diet.
Most Britons know the link between salt intake and high blood pressure, yet we still eat on average, half a teaspoon more than our recommended daily limit. Too much salt in the bloodstream can lead to a build-up of excess fluid, increasing strain on blood vessels which leads to rising blood pressure.
Some scientists believe the healthy fats abundant in the Mediterranean diet, found in nuts, fish, olive oil and some meat, may reduce the inflammatory molecules in the brain (file photo)
Omega-3 helps brain cells to communicate and protects them from damage
It's true that diets high in oily fish, such as tuna, salmon and mackerel, are associated with a reduced risk of a host of diseases, including heart disease, type 2 diabetes and – up to a point – dementia.
Indeed, the NHS recommends that we all eat at least one portion of oily fish a week.
But is it really ‘brain food’, as its vocal supporters claim?
A type of fat called omega-3, which is abundant in the cells of oily fish but which is also produced by our bodies, help our brain cells to communicate and protects them from damage.
Omega-3 has long been proven to be important for cognitive development and memory in adults. But the evidence showing that regularly eating oily fish prevents dementia remains weak.
Some research has shown that people who eat lots of oily fish are less likely to get dementia, but other studies show the opposite.
And research has not yet been able to show that eating more oily fish increases the amount of omega-3 in the brain enough to boost cognition.
Experts believe the association between diets that are high in oily fish and reduced dementia risk may instead be due to the fact