Entry #: 12
Date: 20 September 2017
Section: Mediterranean diet
Type: Human volunteer trial
OliveNetTM Journal Club
Expert review of literature related to olives and olive oil
D. Elizabeth McCord, Nancy B. Ray and Tom C. Karagiannis
High adherence to the Mediterranean diet is associated with cardiovascular protection in higher but not in lower socioeconomic groups: prospective findings from the Moli-sani study
Bonaccio et al
International Journal of Epidemiology, 2017, 1-10; doi: 10.1093/ije/dyx145
Mediterranean diet, cardiovascular disease, socioeconomic status, micronutrients, antioxidants
Adherence to the Mediterranean diet has been with protection from cardiovascular diseases (1-3). This work represents a large community-based prospective study aimed at further stratifying the beneficial effects of the Mediterranean diet with respect to education levels and socioeconomic status. Overall, the findings indicated an association between adherence to the Mediterranean diet and decreased risk in cardiovascular events, which were much more significant in the educated and relatively high-income population group. As concluded by the authors the differences observed for the less educated, low-income group compared to the more highly educated, high-income group may be due to disparities in the intake micronutrients, including antioxidants and polyphenols. Indeed, better overall food selection behaviours according to established recommendations (for example, fish consumption instead of red meat, organic vegetables and whole grain bread), were observed in the higher socioeconomic group compared to the lower socioeconomic group.
Key points and implications
These are profound and new insights taking advantage of a large prospective cohort study. The Moli-sani (Southern Italy) study involves the initial random recruitment of 24,325 participants (1, 4) and the data presented in this study represents 18,991 individuals aged 35 years and above. The final cohort was carefully selected to reduce confounding variable particularly those associated with previous history of cardiovascular disease, diabetes and extreme daily energy intakes. The Mediterranean Diet Score was used to assess adherence to the Mediterranean diet (3), and antioxidant content (5), total antioxidant capacity (6), and polyphenol content (7) was measured using methodologies described previously. Education status and socioeconomic status was self-reported using questionnaires to assign participants into relevant groups. Like the indirect measurement of antioxidant and polyphenol content, self-reporting of diet and socioeconomic status does represent a significant limitation. Nevertheless, the findings are from a very large and well-selected cohort. They are the first to indicate the disparity in cardiovascular events in relatively more highly educated people with a higher socioeconomic status adhering to the Mediterranean diet, compared to people with relatively lower levels of education and income. If these findings hold, they have serious implications from a public health perspective.
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