Michael Georgoulis

Mediterranean Diet and Diabetes: Prevention and Treatment

The aim of the present review is to examine current scientific knowledge on the association between the Mediterranean diet and diabetes mellitus (mostly type 2 diabetes). A definition of the Mediterranean diet and the tools widely used to evaluate adherence to this traditional diet (Mediterranean diet indices) are briefly presented. The review focuses on epidemiological data linking adherence to the Mediterranean diet with the risk of diabetes development, as well as evidence from interventional studies assessing the effect of the Mediterranean diet on diabetes control and the management of diabetes-related complications. The above mentioned data are explored on the basis of evaluating the Mediterranean diet as a whole dietary pattern, rather than focusing on the effect of its individual components. Possible protective mechanisms of the Mediterranean diet against diabetes are also briefly discussed.

Blood redox status is associated with the likelihood of nonalcoholic fatty liver disease irrespectively of diet's total antioxidant capacity

It is well established that oxidative stress is implicated in nonalcoholic fatty liver disease pathogenesis, whereas the dietary intake of antioxidants has been reported to be low in patients with the disease. We hypothesized that blood redox status measurements would be associated with nonalcoholic fatty liver disease presence and severity, and that diets total antioxidant capacity could moderate the aforementioned association. The study sample consisted of 73 patients with nonalcoholic fatty liver disease, of which 58 were matched by age, sex, and body mass index with 58 controls. Diets total antioxidant capacity was estimated through the ferric-reducing antioxidant power, the total radical-trapping antioxidant parameter, and the Trolox equivalent antioxidant capacity scores, whereas blood redox status was assessed by measuring thiobarbituric acid reactive substances levels, the enzymatic activity of glutathione peroxidase, and serum resistance to oxidation. Diets total antioxidant capacity scores and glutathione peroxidase activity were not significantly associated with the disease presence or severity. Both thiobarbituric acid reactive substances and serum resistance to oxidation were significantly associated with the likelihood of nonalcoholic fatty liver disease (odds ratios [ORs], 7.769 [P= .007] and 0.936 [P= .033], respectively), independently of abdominal fat level, degree of insulin resistance, blood lipid levels, markers of subclinical inflammation, and diets total antioxidant capacity, but not with the disease histologic severity or stage. Our results support the association between blood redox status and the likelihood of nonalcoholic fatty liver disease regardless of diets total antioxidant capacity.

Increased abdominal fat levels measured by bioelectrical impedance are associated with histological lesions of nonalcoholic steatohepatitis.

Background/aim Abdominal fat is considered to play an important role in nonalcoholic fatty liver disease (NAFLD), although it is not adequately studied because abdominal fat levels cannot be estimated easily. In this study, associations between abdominal obesity, as assessed by abdominal bioelectrical impedance analysis (BIA), and the characteristics of patients with NAFLD were explored. Patients and methods Seventy-four consecutive NAFLD patients who underwent measurement of abdominal fat levels by BIA were included. Levels of abdominal fat 12.5 or less and more than 12.5 were considered to be average and increased, respectively. Results The mean±SD BMI was 30±4 kg/m2 and the mean abdominal fat levels were 16±5, whereas 26% of patients had average abdominal fat levels. Patients with average compared with those with increased abdominal fat levels were more frequently women (50 vs. 12%, P=0.001), had lower BMI (27±3 vs. 31±4 kg/m2, P<0.001), lower Homeostasis Model Assessment index (2.6±1.4 vs. 3.9±2.7, P=0.045), and lower median liver stiffness on transient elastography (5.3 vs. 6.8 kPa, P=0.025). In patients with available liver biopsy, steatohepatitis was present more frequently in patients with increased compared with average abdominal fat levels (78 vs. 38%, P=0.030) and in patients with BMI 30 or more compared with less than 30 kg/m2 (87 vs. 48%, P=0.033), but similar in patients with increased or normal waist circumference (67 vs. 56%, P=0.693). Conclusion Average levels of abdominal fat, as assessed by abdominal BIA, are mainly present in female patients with NAFLD and are associated with a lower degree of insulin resistance. Increased abdominal fat as assessed by BIA and obesity seem to represent strong risk factors for histological steatohepatitis.

Association of Anthropometric and Lifestyle Parameters with Fitness Levels in Greek Schoolchildren: Results from the EYZHN Program

Objective The aim of the study was to evaluate physical fitness (PF) and identify its anthropometric and lifestyle determinants in a sample of Greek schoolchildren. Methods The study sample consisted of 335,810 schoolchildren (♂: 51.3%, 6–18 years old). Students’ anthropometric parameters and PF levels—assessed via the Eurofit test battery—were measured by trained physical education teachers and evaluated according to the available norms, while their lifestyle habits were assessed through a questionnaire. Results In all applied PF tests, students’ performance was negatively associated with the presence of obesity and central obesity, defined through international criteria for body mass index and waist to height ratio, respectively. According to multiple logistic regression analysis, the presence of overweight/obesity [odds ratio (OR): 4.43, 95% confidence interval (CI): 3.98–4.93], low adherence to the MD (KIDMED ≤ 3) (OR: 1.27, 95% CI: 1.09–1.48), and increased time spent in sedentary activities (>2 h per day) (OR: 1.16, 95% CI: 1.03–1.29) were positively associated with poor PF, after adjusting for age and sex. In contrast, for every 1 day increase in the weekly frequency of engagement in athletic activity, the probability of poor PF decreased by 26% (OR: 0.74, 95% CI: 0.72–0.77). In a similar model, the presence of central obesity emerged as an even stronger possible predictor of poor PF (OR: 5.20, 95% CI: 4.66–5.78), compared to the presence of general obesity. Conclusion Higher general or abdominal adiposity, as well as the adoption of a low-quality diet and a sedentary lifestyle, is strongly associated with low PF levels during childhood.