Entry #: 3
Date: 3 July 2017
Section: Mediterranean Diet
Topic: Minoan Isolates (MANOLIS) dietary study
Type: Public Health
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The mountainous Cretan dietary patterns and their relationship with cardiovascular risk factors: The Hellenic Isolated Cohorts MANOLIS study
Farmaki A-E et. al.
Citation / Year
(1) / 2016
Hellenic isolated cohorts, Cretan dietary patterns, olive oil, cardiovascular disease, diabetes, obesity
The Seven Countries Study Cretan seven countries was the first major study to identify and document associated with the Mediterranean diet (2). In particular, the males from rural Cretan villages that were followed in the seminal study were recognized for their health and longevity. In this study, the target cohort comprised of adults from the Mylopotamos region (on Mount Idi) in Crete which includes the communities of Anogia, Zoniana and Livadia. In general, the inhabitants of this geographically isolated, high-altitude region are known for their health and longevity. They have retained their customs and traditions including a diet relatively high in animal fat. Overall, 1553 (55.8% female; mean age = 61.6 years [elderly population] participants were followed and divided into four dietary patterns which were classified as: 1) ‘local’ (homemade pies, legumes, red meat, full-fat cheese and refined cereals), 2) ‘high fat and sugar’ (chocolate, milky and starchy sweets, simple sugars, ready-made pies, cheese flavoured snacks/chips, 3) ‘Greek café/tavern’ (coffee, alcohol, olives and fries), and 4) ‘olive oil, fruits and vegetables’. Interestingly, a large proportion of the total population of the region (29.7%) participated in the study. Along with blood pressure, a range of well-established anthropometric (weight, height, body mass index, waist and hip circumferences, and waist:hip ratios), and biochemical (glucose, insulin, total cholesterol, HDL cholesterol, LDL cholesterol [calculated] and triglyceride), were measured. Overall, weak associations were made in this study; a higher waist:hip ratio, blood pressure and cholesterol was reported for the Greek café/tavern diet and higher blood pressure for those in the local dietary pattern cohort. The olive oil, fruits and vegetable diet pattern was associated with an improvement in systolic blood pressure however, was also associated with high body mass index and waist:hip ratio. In general, the findings are not as convincing as those previously reported for the health benefits of the Mediterranean diet, particularly, diets with an emphasis on olive oil (3, 4).
Key points and implications
As self-reported by the authors there are a number of limitations of some of the approaches used in this study. The most obvious is the classification of the four different dietary patterns. Although the authors did describe a detailed principal components analysis and linear regression analyses to aid, the classification was based on inductive reasoning (posteriori) and subjective. Nevertheless, this study is interesting given the large isolated Cretan cohort lending itself to detailed analyses. For example a subsequent study has used parts of this cohort to perform whole genome sequencing identifying novel low-frequency genetic variants associated with cardioprotective effects (5). The variant rs145556679* is receiving much recent attention and may be a unique variant associated with lower triglycerides in the Mylopotamos population.
- A. E. Farmaki et al., The mountainous Cretan dietary patterns and their relationship with cardiovascular risk factors: the Hellenic Isolated Cohorts MANOLIS study. Public Health Nutr 20, 1063-1074 (2017).
- A. Keys et al., The diet and 15-year death rate in the seven countries study. Am J Epidemiol 124, 903-915 (1986).
- T. Psaltopoulou et al., Olive oil, the Mediterranean diet, and arterial blood pressure: the Greek European Prospective Investigation into Cancer and Nutrition (EPIC) study. Am J Clin Nutr 80, 1012-1018 (2004).
- A. Alonso, V. Ruiz-Gutierrez, M. A. Martinez-Gonzalez, Monounsaturated fatty acids, olive oil and blood pressure: epidemiological, clinical and experimental evidence. Public Health Nutr 9, 251-257 (2006).
- L. Southam et al., Whole genome sequencing and imputation in isolated populations identify genetic associations with medically-relevant complex traits. Nat Commun 8, 15606 (2017).
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