The Mediterranean diet is not an exact meal plan but rather a collection of dietary habits. The Mediterranean way relies primarily on plant-based foods such as fruits, vegetables, grains, legumes, and nuts. Red meat is eaten rarely, opting instead for fish and poultry at least twice per week and healthy fats such as olive oil and canola oil instead of saturated fats. Over the past few years some of these individual dietary habits have been associated with a variety of health benefits such as improving heart health and decreasing risk of certain cancer or diabetes.
Researchers from Italy examined the benefits of the Mediterranean diet by the rate of adherence to the diet. The study, published in the American Journal of Clinical Nutrition, found that increased adherence to the diet was significantly associated with lower risks of death, cardiovascular disease, cancer, Parkinson's and Alzheimer's disease.
About the Study
The study was a systematic review that included 18 cohort studies with 2,190,627 participants. Adherence to the diet was measured on a scale of 0-9 with higher adherence earning higher numbers. A two-point increase in adherence was associated with:
- 8% decrease in all cause mortality (in analysis of 9 studies with 514,118 participants)
- 10% lower risk of cardiovascular disease or cardiovascular death (in analysis of 8 studies with 534,064 participants)
- 6% lower risk of cancer or cancer death (in analysis of 7 studies with 1,006,410 participants)
- 13% lower risk of Parkinson's disease and Alzheimer's disease (in analysis of 5 studies with 136,235 participants)
How Does This Affect You?
Systematic reviews can help clarify a research question by pooling several smaller studies together. A larger number of participants and occurrences generally increases the reliability of the results, but this systematic review was based on observational studies, which decreases the reliability of the outcomes. Observation studies cannot control for all the factors that may be different between groups. The results we see may actually be due to some unseen difference between the patients that adhered to the diet rather than the diet itself.
Even with the trial limitations, the results are similar to several other studies about Mediterranean diet. In addition, the individual habits of the diet, such as high amounts of fruits and vegetables and good fats, have individually been associated with many health benefits so it is likely that this diet has these health benefits. The good news is that the Mediterranean diet does not require severe restrictions or avoidance of particular foods. To develop a healthier diet start with small steps. Gradually increase your daily fruits and vegetables, try swapping out saturated fats with healthier options like olive or canola oil, and keep red meats to a minimum. Explore new recipes with Mediterranean influence to keep your diet fresh.
- Reviewer: Brian P. Randall, MD
- Review Date: 04/2011 -