The Mediterranean Diet: Science Behind The Health Claims

BY CHLOE FRENCH, ANUTR

 
 
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Although you may associate Mediterranean food with pizza, ice cream and wine; the typical diet of populations surrounding the Mediterranean Sea actually consists of fruit, vegetables, legumes, nuts, whole grains, fish and extra virgin olive oil.

This dietary pattern has received attention over the last few years, as it seems to provide a range of health benefits and protection against certain types of disease. 

What is the evidence?

Many studies have found that following a Mediterranean diet has been associated with longevity and a lower prevalence of several chronic diseases including cardiovascular disease, Alzheimer’s, obesity and some types of cancer (1). The reduced risk of disease seems to come from the dietary pattern as a whole rather than the consumption of specific “super foods”.

This dietary pattern provides a balanced ratio of omega 6 to omega 3 fatty acids with olive oil, fish and nuts providing the main sources of fat (1). In addition, the high consumption of fruit, vegetables and legumes provides a source of fibre, antioxidants and vitamins that help to reduce inflammation and oxidative stress (2).

Several large observational studies have found that adherence to a Mediterranean diet is associated with a reduced risk of cognitive impairment and decline even after considering other lifestyle and genetic factors (3, 4). 

Randomised controlled trials (RCT) have also been conducted to understand the role of this eating pattern on health outcomes. A RCT randomly splits participants so that one group receives an intervention and the other group does not (control) in order to compare the difference in response between the groups. PREDIMED was a large RCT involving individuals with a high risk of heart disease. Individuals were placed on one of three diets but not asked to change their calorie intake or level of physical activity (5).

  • Group A: Mediterranean diet with added extra virgin olive oil

  • Group B: Mediterranean diet with added nuts

  • Group C: Low fat diet (Control group) 

After following the diets for 5 years many health outcomes were compared between the groups. The study found that a Mediterranean diet supplemented with extra virgin olive oil or nuts resulted in a 30% relative risk reduction of cardiovascular disease (5). In addition, both Mediterranean diets were more effective compared to the control group for weight loss and preventing type 2 diabetes.

This type of trial is considered the gold standard as it allows a direct comparison to be made to understand the specific effect of the Mediterranean diet on health outcomes.

PREDIMED demonstrates that a Mediterranean diet with a high consumption of olive oil, fruits, vegetables, nuts and legumes may be responsible for these important health benefits (6).

 
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How to eat in a more Mediterranean style

Eat more fruit and vegetables

Check out the Great British Veg Out for a list of simple and healthy recipes to help you achieve your 5 a day. 

Utilise extra virgin olive oil

This can be great in a salad dressing or drizzled over fish or vegetables before roasting.  It can also be a great alternative to butter with bread, potatoes or even in baking. 

Decrease meat consumption

Replace red or processed meat for fish, chickpeas, egg or tofu. 

Snack smartly

A handful of nuts, hummus and crudités or an apple with peanut butter are great balanced, filling and healthy snack options. 

Enjoy red wine with meals

Alcohol is not essential, but a glass of red wine with your meal is considered healthy as part of the Mediterranean diet. This may also help you enjoy and take your time over a meal so that you eat slower and therefore, appreciate the food and have a greater ability to recognise your fullness cues. 

Live the Mediterranean way

As well as adapting your diet to the Mediterranean way, there are certain aspects of the Mediterranean lifestyle that we could also benefit from such as; having an active lifestyle, getting out in nature, enjoying meals with family and friends. All of which can have a positive impact on our general wellbeing and mental health.

 
 

 

About the author:

Chloe French is a Registered Associate Nutritionist spreading her time between working as a freelance Nutritionist and researching the prevalence and severity of food allergies at the University of Manchester. Her aim is to make healthy eating both accessible and interesting. Chloe prioritzes making evidence-based research relevant to our every day life by educating, inspiring and providing tasty and nutritious recipes. This is important to improve our health, performance and energy levels (both mentally and physically). 

 


References

  1. Yannakoulia, M. Kontogianni, M and Scarmeas, N. Cognitive health and Mediterranean Diet: Just diet or lifestyle pattern? (2015) Ageing Research Reviews. 20:74-78. 

  2. Estruch, R. Anti-inflammatory effects of the Mediterranean diet: the experience of the PREDIMED study. (2010) Proc. Nutr. Soc. 69:333-340.

  3. Tangney, C.C., Kwasny, M.J., Li, H., et al., Adherence to a Mediterranean-type dietary pattern and cognitive decline in a community population. (2011) Am. J. Clin. Nutr. 93:601-607. 

  4. Feart, C., Samieri, C., Rondeau, V., Amieva, H. et al. Adherence to a Mediterranean diet, cognitive decline, and risk of dementia. (2009) J. Am. Med. Assoc. 203:638-648.

  5. Estruch, R., Ros, E., Salas-Salvadó, J. et al. Primary prevention of cardiovascular disease with a Mediterranean diet supplemented with extra-virgin olive oil or nuts. (2018) New England Journal of Medicine 368;14: 1279-1290

  6. Sofi, C., Macchi, R., Abbate, G.F. et al. Mediterranean diet and health. (2013) Biofactors 39:335-342.