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Cognitive decline and the Mediterranean Diet
The Mediterranean Diet is a well-studied pattern of eating, and as a result, there are a plethora of studies purporting its fantastic-ness for supporting health.
Reduced incidence of weight loss, type 2 diabetes, breast cancer recurrence, and cardiovascular disease have all being associated with eating ‘Mediterranean’.
And now, it seems it is rockin’ for your brain too!
The review
A systematic review was undertaken by a group of Swinburne University of Technology researchers, who collated 135 studies published between 2000 and 2015. Only 18 studies met strict criteria for the review, and upon analysis, it was found higher adherence to the Mediterranean diet reflected in improved cognition, reduced rates of cognitive decline and conversion to Alzheimer’s disease.1
Language and attention improved, with memory, executive function and visual constructs found to be a particular perk of eating Med-style. And benefits have been seen in both younger and older populations.
The Mediterranean diet of countries such as Italy, former Yugoslavia and Greece typify the food pattern analysed. Populations of these countries have seen lower risk of cardiovascular disease, cancer, other chronic condition, and have longer life expectancy.1
Its lack of refined sugar and trans-fats, and high consumption of veg and fruit are what may make it so brain friendly.
Another recently released study supports the notion. Following PET scans in in people aged 40-85 with memory or mild cognitive impairment (but not diagnosed with dementia), it was found that those with lower body mass index (BMI), who engaged in regular exercise and ate a Mediterranean-style diet had less beta-amyloid plaques and tau protein tangles in their brains associated with Alzheimer’s disease and cognitive decline.2
Feeding the brain
As the population ages, and we are living longer, it is important to support physical and mental health. And diet can have a huge role to play!
Key components of the Mediterranean style of diet attributed with health benefits may align more traditional parameters of the diet, rather than a more modern representation, which likely includes more heavily refined and processed meats, grains, sugars and oils.
The supposed beneficial qualities we should be looking to include in our meals are a heavy focus on vegetables and leafy greens, flavouring with herbs and spices, and enjoying legumes and healthy fats from olive oil, fish, and nuts.
By consuming mostly a variety of whole foods, we may change modifiable risk factors for cognitive decline, according to Hardman, including “…reducing inflammatory responses, increasing micronutrients, improving vitamin and mineral imbalances, changing lipid profiles by using olive oils as the main source of dietary fats, maintaining weight and potentially reducing obesity, improving polyphenols in the blood, improving cellular energy metabolism and maybe changing the gut microbiota, although this has not been examined to a larger extent yet.”
A great example of food as medicine!
An accessible way to eat
What is remarkable about the Swinburne University review is the researchers found the benefits from such a diet may be applicable to people around the globe.
“The most surprising result was that the positive effects were found in countries around the whole world. So regardless of being located outside of what is considered the Mediterranean region, the positive cognitive effects of a higher adherence to a MedDiet were similar in all evaluated papers,” said lead study author Roy Hardman.
Importantly, there may be some stick with the Mediterranean diet. The focus on real, whole fresh foods means we have a broad selection of fare to choose from. We can then eat by way of inclusion (think about the variety of fresh produce from the grocer, the butcher, and the whole food bulk bins combined – endless possibilities!), rather than strict exclusion.
Let us not forget the lifestyle factors, some attributed to the Med-diet, that could also influence health! Eating good, real food is improved yet again with daily exercise, getting a good night’s sleep, and enjoying time with others. And possibly a cheeky glass of wine.
By Angela Johnson (BHSc Nut. Med.)
References:
- Hardman, RJ, Kennedy, G, Macpherson, H, Scholey, AB, & Pipingas, A 2016, ‘Adherence to a Mediterranean-Style Diet and Effects on Cognition in Adults: A Qualitative Evaluation and Systematic Review of Longitudinal and Prospective Trials’, Frontiers in Nutrition, [Epub]
- Merrill, DA Siddarth, P Raji, CA Emerson, ND Rueda, F Ercoli, LM Miller, KJ Lavretsky, H Harris, LM Burggren, AC Bookheimer, SY Barrio, JR & Small, GW 2016, ‘Modifiable Risk Factors and Brain Positron Emission Tomography Measures of Amyloid and Tau in Nondemented Adults with Memory Complaints’, American Journal of Geriatric Psychiatry, [Epub ahead of print].
