Are you eating your five a day – and olive oil, nuts and fish? Now there’s more reason to eat Mediterranean.
We’ve known for a while now that eating a Mediterranean diet is good for our health. A new study now adds some extra weight to it brain-boosting reputation.
The study researchers, from the University of Navarra in Spain studied 522 men and women aged between 55 and 80 years old. All were at high vascular risk (high risk of problems related to their blood vessels) because of underlying diseases or conditions.
These included type 2 diabetes or three out of these elements – high blood pressure, an unfavourable blood fat profile (eg high levels of LDL (‘bad’) cholesterol), being overweight, a family history of early cardiovascular disease (eg a heart attack), and being a smoker. None actually had cardiovascular disease at the beginning of the study.
The volunteers were randomly given either a) a Mediterranean diet with added extra virgin olive oil or b) with added mixed nuts, or c) were placed in the control group who received advice to follow a low-fat diet, generally recommended to prevent heart attack or stroke.
Virgin olive oil is a staple part of a Mediterranean diet, which also includes a high proportion of fruits, nuts, vegetables and pulses. Fish and seafood make up a moderate to high proportion of the diet, with low levels of dairy products and red meat. A moderate amount of red wine is also a typical element of this approach to diet.
The volunteers followed their assigned diets for an average of six and a half years. Over this time they had regular check-ups with their family doctor, and had checks every three months to see how well they were keeping to their diet.
At the end of the study they were tested for signs of cognitive decline. The tests involved a Mini Mental State Exam and a clock drawing test. These assess what are known as higher brain functions, such as orientation, memory, language visuo-spatial and visuo-construction abilities. They also assess what are known as executive functions – working memory, attention span and abstract thinking.
Sixty of the people taking part were found to have developed mild cognitive impairment. 18 of these were on the added olive oil diet, 19 were on the added nut diet and 23 were in the control group, following the low-fat diet. Another 35 people were found to have developed dementia. Of these 12 were on the added olive oil diet, six on the added nut diet and 17 were in the control group.
The results of both tests showed that those taking part who were following either of the Mediterranean diets – with additional olive oil or nuts – had significantly higher score than those on the low fat diet.
The scientist behind the study point out that the study is relatively small. And because it looked at people with high vascular risk, the results may not apply to the population as a whole. However, this study does add more weight to the increasing amount of evidence that suggests that a good quality diet seems to protect our cognitive function as we grow older.
A dietitian and spokesperson for the British Dietetic Association (BDA), agrees. “We’ve had all sorts of evidence that the Mediterranean diets is protective for heart disease, is an anti-inflammatory and helps to reduce cholesterol levels.”
“All these are related to cognitive function – you don’t get the build-up of plaques in your arteries or brain – so it all makes sense. If you were to ask me which is the best all-round diet for health, I would say the Mediterranean diet.”
“I know that in the dietetic community we are wondering whether it might be more important to talk about having the right kind of fats rather than cutting fats generally, though there’s no consensus yet. Maybe we should swap fats so that we have fewer saturated fats (for instance, those found in butter, biscuits, cheese, cream and sausages) and more mono-unsaturated fats, like olive oil.”