Supporting Cognitive Health by Eating a Mediterranean-Style Diet

Mediterranean Diet You’ve probably heard by now that there are various heart-health benefits associated with a Mediterranean-style diet, but did you know that eating this way could also be good for your brain? Think smart and drop the low-fat diet for a healthy, antioxidant-rich Mediterranean diet full of fresh fruits, vegetables, nuts, seeds, and a range of healthy fats that keep your grey matter happy.

What is a Mediterranean Diet?

Diets described as Mediterranean tend to include olive oil as the main source of fat and have a high proportion of plant-based foods including fruits and nuts, vegetables, legumes, and whole grains. Some seafood and fish are usually included, with lower consumption of dairy and meat. Moderate alcohol consumption is also often a feature of a Mediterranean-style diet, generally in the form of red wine with meals. This provides a source of the antioxidant resveratrol.

This type of diet is thought to help keep inflammation low, protect cells from free radical and oxidative damage, encourage healthy immune system function, and encourage healthy blood pressure and circulation.

Choose Healthy (Unsaturated) Fats

The Mediterranean diet focuses on healthy fats from nuts, seeds, olive oil, and fish. Around 35–40% of daily calories come from these healthy monounsaturated and polyunsaturated fats in a Mediterranean diet. These fats, which include essential fatty acids omega-3 and omega-6, have been associated with a myriad of benefits for cardiovascular and cognitive health.

In contrast, saturated fats are limited in a Mediterranean diet. This means reducing or eliminating consumption of butter, palm oil, and fats from animal products such as meat and dairy.

Some simple ways to switch saturated fats for unsaturated include:

  • Dipping bread in olive oil and herbs instead of using butter
  • Switching meat-based dishes at lunchtime to dishes featuring olives, nuts, seeds, and avocado
  • Choosing a fortified almond or other non-dairy milk in place of full-fat cow’s milk
  • Making homemade Brazil nut parmesan (grind nuts, nutritional yeast, and a dash of salt in a food processor) and use this in place of dairy cheese
  • Choosing hummus, tapenade, and other plant-based dips instead of mayonnaise and other dairy-based dips

Could maintaining a healthy, happy brain be simply a matter of eating delicious Mediterranean-style food?

What the Research Says

Several studies now suggest brain benefits from a Mediterranean-style diet. A 2016 review of 32 studies, including 5 randomized controlled trials and 27 observational studies, found that the majority of the studies showed this type of diet is associated with “improved cognitive function, a decreased risk of cognitive impairment or decreased risk of dementia”.[1]

One key early study involved 522 volunteers who were at high risk of vascular disease (which is indicated in around 40% of cases of dementia). Half of the participants were men and the average age was just under 75. During this study, participants ate either a low-fat diet as a control or a diet supplemented with either extra virgin olive oil or mixed nuts. After 6.5 years of the dietary interventions, researchers assessed the cognitive function of the volunteers by administering a Mini-Mental State Examination (MMSE) and a Clock Drawing Test (CDT).

The results showed that those eating a diet that included extra virgin olive oil or mixed nuts had higher MMSE and CDT scores compared to those eating a low-fat diet. For the olive oil diet, participants scored 62% higher for MMSE and 51% higher for CDT compared to controls. The mixed nuts group had scores 57% and 33% higher for MMSE and CDT, respectively, compared to controls.[2]

To make sure that other factors weren’t clouding the results, researchers took into account a whole range of things that can affect cognitive performance and cognitive decline, including:

  • Sex
  • Age
  • Education
  • Apolipoprotein E genotype
  • Family history of cognitive impairment/dementia
  • Smoking
  • Physical activity
  • Body mass index
  • Hypertension
  • Dyslipidaemia
  • Diabetes
  • Alcohol
  • Total energy intake

Based on these studies, it’s evident that eating a Mediterranean-style diet is just one of the ways in which you can support good brain health throughout life. Quitting smoking, staying physically active, avoiding a sedentary lifestyle, and keeping blood glucose under control are also important. In addition, it helps to minimize alcohol intake, maintain a healthy body weight, and learn to manage stress effectively in healthy ways.

Diet and Alzheimer’s Disease

Public health officials estimate that a staggering 65.7 million people worldwide will suffer from dementia by 2030. Given that there’s no known cure for Alzheimer’s disease, the race is on to find cost-effective ways to prevent this form of dementia, as well as vascular dementia.

Several nutrients look like good candidates for inclusion in a brain-boosting diet. Essential fatty acids are one such nutrient, with considerable research supporting the benefits of omega-3 from flaxseeds, walnuts, and fish. Evidence is also starting to support benefits from nutrients such as B vitamins that help keep levels of homocysteine in check, a substance associated with poor cardiovascular and cognitive health.

Studying diet and cognitive decline in humans is a particularly tricky process given that we tend to change how we eat over the course of our lifetime. It’s also really hard to point to a single dietary change and claim that it alone is responsible for a specific change in health. Researchers have instead begun to focus more on overall dietary patterns, such as a diet including healthy fats like the Mediterranean-style diet compared to a low-fat diet.

Whether you’re interested in the potential brain benefits of a Mediterranean-style diet, or are just looking for a delicious dinner idea, here’s a recipe inspired by the Mediterranean!

Sicilian Broccoli Affogati

Serves 4

  • 4 tbsp olive oil
  • 1 onion, sliced
  • 3 cups broccoli, florets
  • 2 red bell peppers in inch-square chunks
  • 1 cup cooked chickpeas
  • 1/3 cup black olives, sliced (optional)
  • 1/4 cup partially crushed walnuts
  • 1 cup water
  • 1 cup red wine
  • 1 tsp salt

Heat the olive oil over medium heat in a large sautée pan and add in the sliced onion. Cook until translucent then add the chickpeas and pepper. Stir for a couple of minutes before adding the broccoli. At a moderate-high temperature, add the water and salt and cook until the water evaporates. Add in the walnuts, olives (if using) and wine and simmer for 10 minutes or so, until the broccoli is al dente.

Serve over pasta or with fresh wholegrain bread and drizzle with olive oil.

References:

[1] Petersson SD, Philippou E. Mediterranean diet, cognitive function, and dementia: a systematic review of the evidence. Adv Nutr. 2016 Sep 15; 7(5):889-904.

[2] Martínez-Lapiscina EH, Clavero P, Toledo E, et al. Mediterranean diet improves cognition: The PREDIMED-NAVARRA randomised trial. J Neurol Neurosurg Psychiatry. 2013; 84(12):1318-1325.