Following a Mediterranean diet rich in fish can add five years to a person’s life, according to research carried out at Columbia University, New York. The study found that older people who followed a diet consisting of fish, vegetables, fruit, cereals, nuts and oils had a larger brain volume than those who simply ate what they wanted.
Study author Dr Yian Gu said: “These results are exciting as they raise the possibility that people may potentially prevent brain shrinking and the effects of ageing on the brain simply by following a healthy diet. When you consider that eating at least five of the recommended diet components has an association comparable to five years of ageing – that is substantial.”
It has long been known that the long chain polyunsaturated oils present in fish, particularly pelagic species such as herring, mackerel etc, help to prevent, even cure, a whole host of potentially deadly diseases, particularly cardiovascular disease. Now research is pointing up other health benefits derived from eating fish.
The research at Columbia University involved 674 people with an average age of 80 who were not suffering from dementia. They completed a survey about their dietary habits during the past year and had brain scans an average of seven months after the questionnaire was completed.
The participants who more closely followed the Mediterranean diet had a total brain volume of both grey and white matter that was greater than those who did not.
Switching from meat to fish may well play a part in preventing brain shrinkage. Experts said that eating at least three to five ounces (85-142 grams) of fish each week and no more than 3.5 oz (99 grams) of meat a day may play a part in providing “considerable protection against loss of brain cells”. It comes as evidence shows that oxidative stress, the body’s inability to detoxify itself, plays a major role in diminishing mental powers.
The results of the study have been welcomed by UK experts who said adopting a healthy lifestyle could help stave off devastating conditions such as dementia.
Hilda Hayo, chief executive officer of the charity Dementia UK, said: “We welcome this research. A balanced diet and healthy lifestyle is vital for brain health and could help lower the risk of dementia.
Dr James Pickett, head of research at the Alzheimer’s Society charity, said: “There is an increasing amount of evidence that eating a healthy diet rich in fish, vegetables, legumes and nuts is good for your brain. However, he added: “It does not prove a Mediterranean style diet can stop your brain from shrinking as you age.”
The study was published in the scientific journal Neurology.
Four studies into the effects of a Mediterranean diet on older people were also carried out in Sweden. The “H70 study” compared 70-year-olds on a Mediterranean diet with ¬others of the same age who had eaten more meat and animal products throughout their lives.
The study involved people aged 70 in the Gothenburg region during more than 40 years. Analysis of the results showed that those on a Mediterranean diet had a 20 per cent higher chance of living longer.
“This means that older people who eat a Mediterranean diet live an estimated two to three years longer than those who don’t”, said lead scientist Gianluca Tognon. Dr Tognon, of the Sahlgrenska Academy at the University of Gothenburg, said the H70 findings were supported by three further as yet unpublished studies into the subject.
One was carried out on people in Denmark, a second on people in northern Sweden, and the third on children. “The conclusion we can draw from these studies is that there is no doubt that a Mediterranean diet is linked to better health, not only for the elderly but also for youngsters”, he added.
UK nutritionist Angela Dowden commented: “This adds yet more to the growing evidence base that the Mediterranean diet really is one of the healthiest in the world. Our climate and culture doesn’t lend itself so well to this type of eating, but we can all emulate some of the good points by eating more oily fish, fruit, vegetables and pulses, and snacking on nuts.”
The overall conclusion from this research is that the sooner people adopt a Mediterranean diet the better.