Think Mediterranean and you’re sailing in blue skies and blue seas, dipping bread into olive oil and sipping red wine. Think Mediterranean diet and remember this acronym – PREDIMED.
The PREDIMED diet study is a rare long-term study undertaken by 16 research groups in 7 communities in Spain over 2003-2011. The acronym PREDIMED stands for PREvención con DIeta MEDiterránea (Prevention with Mediterranean Diet). PREDIMED’s objective was to determine whether a long term Mediterranean diet supplemented with additional extra-virgin olive oil or tree nuts, compared to a reduced-fat diet, can prevent cardiovascular diseases (CVD) (cardiovascular death, myocardial infarction and stroke). Researchers also looked for links to incidence of heart failure, diabetes mellitus, cancer and dementia; using blood pressure, fasting blood glucose, lipid profile, inflammatory and other CVD markers. [1,2]
Nearly 7300 older adults at high risk of CVD, but with no symptoms at the start, were followed for around 5 years on average. The age ranges were 55-80yrs for men and 60-80yrs for women. These older people were randomised to three groups: a reduced-fat control diet group which used ordinary olive oil, a Mediterranean diet supplemented with extra-virgin olive oil (EVO) (1L per week) and a Mediterranean diet supplemented with nuts (30g mixed nuts per day, made up of 15g walnuts, 7.5g almonds and 7.5g hazelnuts). [1,2]
After eight years and over 60 published research papers this study has uncovered many interesting facts about the Mediterranean Diet. Most important however is that the study was ceased ahead of schedule as the results were so surprising the researchers could not ethically allow the control group to continue and not reap the benefits of eating nuts and using extra virgin olive oil.
In relation to nuts specifically however:
- Those following the Medit+Nuts diet had a:
- 39% lower risk of obesity,
- 32% lower risk of abdominal obesity,
- 26% lower risk of Metabolic Syndrome and a
- 13% lower risk of diabetes compared to the reduced fat group. 
- After five years there were fewer incidences of cardiovascular deaths, heart attacks and strokes in those following the Medit+EVO and Medit+Nuts diet groups compared to the reduced fat group. Those following the Medit+Nuts diet had a:
- 28% lower risk of any cardiovascular end point and especially a
- 46% reduced risk of stroke. 
PREDIMED studies also found the potential mechanisms to help explain these results. Eating a Medit+Nuts diet helps to:
- Reduce lousy LDL cholesterol and triglycerides while preserving healthy HDL cholesterol – risk factors for heart disease 
- Reduce blood glucose levels needed for diabetes control 
- Manage weight by affecting Body Mass Index and waist circumference which decreased by 0.78kg/m2 and 2.1cm respectively, for each additional serving of nuts eaten. 
- Increase antioxidants and anti-inflammatory compounds such as resveratrol to help reduce inflammation. 
In a nut shell …..the PREDIMED diet shows that although nuts are high in fat and energy we should all be including a 30g handful of mixed nuts each day as part of a healthy Mediterranean diet. This diet should also include: extra virgin olive oil, fruit, vegetables, legumes, wholegrains, fish, lean meat and reduced fat dairy. Together they help reduce the risk of heart disease and diabetes and most surprising of all play a role in weight management. Eating small regular amounts of plant foods rich in healthy fats is not “fattening”. It’s time to bust the myth and move beyond the low fat diet to a healthy fat diet for weight management.
 PREDIMED Study Group. https://predimed.onmedic.net/
 Protocol, PREDIMED Research. Available at https://predimed.onmedic.net/
 Ibarrola-Jurado N et al Cross-Sectional Assessment of Nut Consumption and Obesity, Metabolic Syndrome and Other Cardiometabolic Risk Factors: The PREDIMED Study. PLoS One. 2013;8(2):e57367.
 Estruch R et al Primary Prevention of Cardiovascular Disease with a Mediterranean Diet. N Engl J Med.2013;368(14):1279-1290.
 Casas-Agustench P, et al. Cross-sectional association of nut intake with adiposity in a Mediterranean population. Nutr Metab Cardiovasc Dis. 2011;21(7):518-25.
 Zamora-Ros R, et al. High urinary levels of resveratrol metabolites are associated with a redcution in he prevalence of cardiovascular risk facors in high risk patients. Pharmacol Res. 2012;65(6):615-20.