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Featured researches published by George Mamalakis.


International Journal of Obesity | 2000

Obesity indices in a cohort of primary school children in Crete: a six year prospective study.

George Mamalakis; A Kafatos; Yannis Manios; T Anagnostopoulou; I Apostolaki

OBJECTIVE: To report on the body mass index (BMI), waist-to-hip ratio (WHR) and sum of skinfolds in a cohort of Cretan children and identify the factors associated with these indices.DESIGN: The present study was a follow-up study. Children were measured prospectively at ages 6, 9 and 12.SUBJECTS: Pupils came from 40 schools randomly selected from the 541 primary schools in three different provinces of Crete. 1046 pupils were examined at age 6. At age 9, a representative sample from the original cohort (n=579) was randomly selected for re-evaluation. At the age of 12, a sample of 831 pupils was re-examined, following similar procedures.MEASUREMENTS: Both during baseline and each subsequent follow-up, data were obtained on pupils’ anthropometry, serum lipids, dietary intake, physical fitness and physical activity as well as their dietary and their health knowledge. Data on parents’ anthropometry, age, occupation, educational level, and issues relating to health habits, attitudes and knowledge were also collected.RESULTS: Half of the obese children at age 6 were also obese at age 12. Cretan children had higher mean BMI than similar American cohorts. Compared to their American counterparts, Cretans had higher proportions of overweight in both genders across all ages tested. The endurance run test (ERT), an index of physical fitness, was positively associated with obesity indices. Sum of skinfolds related positively to serum LDL-C. Children from urban areas had higher skinfold sums than children from rural areas. Parental health-related hedonism related positively to childrens BMI.CONCLUSION: It appears that these findings offer some support to the reported increasing prevalence of obesity among Greek children. Higher ERT, presumably reflecting higher physical activity, is associated with lower obesity. The relationship between degree of fatness and LDL-C appears to be evidenced at an early age in life. This relationship may relate to the reported VLDL and cholesteryl ester transfer protein elevations in obesity. The parental attitude of health-related hedonism appears to be linked with childrens adiposity.


European Journal of Clinical Nutrition | 2006

Depression and long chain n-3 fatty acids in adipose tissue in adults from Crete

George Mamalakis; Nick Kalogeropoulos; Nikolaos K. Andrikopoulos; Christos M. Hatzis; Daan Kromhout; Joanna Moschandreas; A Kafatos

Background:Only one study has investigated the relationship of essential fatty acids in the adipose tissue with depression in adults and suggested an inverse relationship between docosahexaenoic acid (22:6 n-3) (DHA) and depression.Objective:To examine the relation between adipose tissue polyunsaturated fatty acids especially n-3 and n-6 fatty acids, an index of long-term or habitual fatty acid intake, and depression in adults.Design:Cross-sectional study of healthy adults from the island of Crete.Setting:The Preventive Medicine and Nutrition Clinic, University of Crete, Greece.Subjects:A total of 130 healthy adults (59 males, 71 females) aged 22—58 years. The sample was a sub-sample of the Greek ApoEurope study group.Methods:Fatty acids were determined by gas chromatography in adipose tissue. Information about depression was obtained through the Zung Self-rating Depression Scale.Results:Adipose tissue DHA was inversely related with depression. Multiple linear regression analysis taking into account the possible confounding effect of age, gender, body mass index, smoking and educational level confirmed this association.Conclusions:The inverse relationship between adipose DHA and depression in adults, replicates findings of a previous study. This relationship indicates that a low long-term dietary intake of DHA is associated with an increased risk for depression in adults.Funding:The International Olive Oil Council and the DG XII of the European Union.


BMC Public Health | 2003

Effects of Greek orthodox christian church fasting on serum lipids and obesity

Katerina Sarri; Nikolaos Tzanakis; Manolis Linardakis; George Mamalakis; Anthony Kafatos

BackgroundNo study to date has focused on the impact of Greek Orthodox Christian fasting on serum lipoproteins and obesity yet.Methods120 Greek adults were followed longitudinally for one year. Sixty fasted regularly in all fasting periods (fasters) and 60 did not fast at all (controls). The three major fasting periods under study were: Christmas (40 days), Lent (48 days) and Assumption (August, 15 days). A total of 6 measurements were made during one year including pre- and end-fasting blood collection, serum lipoprotein analyses and anthropometric measurements.ResultsStatistically significant end-fasting total and LDL cholesterol differences were found in fasters. Fasters compared to controls presented 12.5% lower end-total cholesterol (p < 0.001), 15.9% lower end-LDL cholesterol (p < 0.001) and 1.5% lower end-BMI (p < 0.001). The end- LDL/HDL ratio was lower in fasters (6.5%, p < 0.05) while the change in end- HDL cholesterol in fasters (4.6% decline) was not significant. Similar results were found when the pre- and end-fasting values of fasters were compared. No change was found in control subjects.ConclusionsAdherence to Greek Orthodox fasting periods contributes to a reduction in the blood lipid profile including a non-significant reduction in HDL cholesterol and possible impact on obesity.


Pharmacology, Biochemistry and Behavior | 2006

Depression and serum adiponectin and adipose omega-3 and omega-6 fatty acids in adolescents

George Mamalakis; Michael Kiriakakis; George Tsibinos; Christos M. Hatzis; Sofia Flouri; Christos S. Mantzoros; Anthony Kafatos

The purpose of the present study was to investigate for a possible relationship between depression and serum adiponectin and adipose tissue omega-3 and omega-6 PUFA. The sample consisted of 90 healthy adolescent volunteers from the island of Crete. There were 54 girls and 36 boys, aged 13 to 18. The mean age was 15.2 years. Subjects were examined by the Preventive Medicine and Nutrition Clinic of the University of Crete. Depression was assessed through the use of the Beck Depression Inventory (BDI) and the Center for Epidemiologic Studies Depression Scale (CES-D). Fatty acids were determined by gas chromatography in adipose tissue. CES-D correlated with dihomo-gamma linolenic acid (DGLA). Multiple linear regression analyses showed that BDI was negatively associated with eicosapentaenoic acid (EPA), while CES-D was positively associated with DGLA in adipose tissue. Serum adiponectin was not significantly associated with depression. The negative relationship between adipose EPA and depression in adolescents, is in line with findings of previous studies involving adult and elderly subjects, demonstrating negative relations between depression and adipose omega-3 PUFA. This is the first literature report of a relationship between depression and an individual omega-3 fatty acid in adolescents. The inverse relationship between adipose EPA and depression indicates that a low long-term dietary intake of EPA is associated with an increased risk for depression in adolescents.


European Journal of Clinical Nutrition | 2006

Depression and adipose and serum cholesteryl ester polyunsaturated fatty acids in the survivors of the seven countries study population of Crete

George Mamalakis; Eugene Jansen; H Cremers; M Kiriakakis; G Tsibinos; Anthony Kafatos

Background:Studies have shown that depression relates to biomarkers of both short- and long-term polyunsaturated fatty acid (PUFA) intake. However, it is not known which of these two biomarkers has the closest relationship to depression.Objective:To examine the relationship of depression with both adipose tissue and serum cholesteryl ester PUFA and to assess the importance of each of these two biomarkers in relating to depression.Design:Cross-sectional study of healthy elderly men from the island of Crete.Setting:The Preventive Medicine and Nutrition Clinic, University of Crete, Greece.Subjects:A total of 150 males, aged 80–96 years. The subjects were survivors of the Greek Seven Countries Study group.Methods:Fatty acids were determined by gas chromatography in adipose tissue and serum cholesteryl esters. Information about depression was obtained through the use of the short form of the Geriatric Depression Scale (GDS-15).Results:Regression analysis showed that depression related positively to age and serum cholesteryl ester arachidonic/docosahexaenoic fatty acid ratio. The only significant unadjusted correlation between depression and serum cholesteryl ester and adipose fatty acids was with adipose alpha-linolenic acid (ALA) (r=−0.31, P<0.01). Depressed males (GDS-15>5) had lower adipose ALA and sum n-3 fatty acids than non-depressed ones. There were no significant differences between depressed and non-depressed males in serum cholesteryl ester fatty acids. When adipose tissue ALA was included as one of the independent measures in the regression model, the observed positive relation between GDS-15 depression and cholesteryl ester arachidonic/docosahexaenoic ratio failed to persist. Instead, there was a negative relationship between GDS-15 depression and adipose tissue ALA.Conclusions:It appears that the fatty acids of the adipose tissue are better predictors of depression than those of serum cholesteryl esters. This indicates that depression relates more strongly to long-term than to short-term fatty acid intake. The reason for this may be the reported slow rate of deposition of dietary PUFA to the brain.


Journal of The American College of Nutrition | 1998

Anxiety and adipose essential fatty acid precursors for prostaglandin E1 and E2

George Mamalakis; Anthony Kafatos; Michalis Tornaritis; Basil Alevizos

OBJECTIVE The purpose of the present study was to investigate the relation state and trait anxiety and adipose tissue essential fatty acid precursors for prostaglandins E1 and E2. METHODS The sample consisted of 144 male and female Cretan adults, 23 to 69 years of age. Anthropometric and arterial blood pressure measurements were taken, and adipose tissue samples as well as data concerning general health habits were collected. Dietary data were collected using the weekly food frequency questionnaire and the 24-hour dietary recall method, while state and trait anxiety was assessed through the use of the Spielberger State-Trait Anxiety Inventory (STAI) and the Zung anxiety scale. RESULTS State anxiety (STAI) related positively with sex (p < 0.0003) and negatively with adipose fat myristic acid (C14:0) (p < 0.004). Similarly, Zung trait anxiety related positively with sex (p < 0.0001) and negatively with adipose tissue myristic acid (C14:0) (p < 0.04). Spielberger trait anxiety related positively with adipose (LA + ALA)/(AA + EPA) ratio (p < 0.0002) and negatively with (C14:0) (p < 0.02) and dietary monounsaturated fat (p < 0.03). CONCLUSION It appears that the positive relation between trait anxiety and adipose (LA + ALA)/(AA + EPA) ratio may stem from the inhibiting role of catecholamines on delta 6 and delta 5 desaturases.


Pharmacology, Biochemistry and Behavior | 2008

Lack of an association of depression with n-3 polyunsaturated fatty acids in adipose tissue and serum phospholipids in healthy adults

George Mamalakis; Michael Kiriakakis; George Tsibinos; Eugene Jansen; Hans Cremers; Carlo Strien; Christos M. Hatzis; Joanna Moschandreas; Manolis Linardakis; Daan Kromhout; Anthony Kafatos

Studies have shown that depression relates to biomarkers of both short-term and long-term polyunsaturated fatty acid intake. However, it is not known which of these two biomarkers is more closely related to depression. The aim of this study was to examine the relationship of depression with both adipose tissue and serum phospholipid polyunsaturated fatty acids and to assess the importance of each of these two biomarkers in relating to depression. This is a cross-sectional study of healthy adults from the island of Crete. Subjects were examined by the Preventive Medicine and Nutrition Clinic of the University of Crete. Subjects were 394 healthy adults (175 males, 219 females) aged 18-60. The sample consisted of farmers from a number of rural communities of Crete. Fatty acids were determined by gas chromatography in adipose tissue and serum phospholipids. Information about depression was obtained through the Beck Depression Inventory (BDI) and Zung Self-rating Depression Scale (ZSRDS). Adipose tissue alpha-linolenic acid (ALA) (C18:3n-3) was inversely correlated to BDI (r=-0.17, p<0.02). Multiple linear regression analysis taking into account the possible confounding effect of age, gender, body mass index (BMI), smoking and educational level did not confirm this association. The other polyunsaturated fatty acids in adipose tissue were not related to depression. Serum phospholipid polyunsaturated fatty acids did not correlate with depression. This study did not show that the polyunsaturated fatty acids in the adipose tissue are better predictors of depression than those in serum phospholipids.


European Journal of Clinical Nutrition | 2002

Abdominal vs buttock adipose fat: relationships with children's serum lipid levels.

George Mamalakis; A Kafatos; Yannis Manios; Nick Kalogeropoulos; Nikolaos K. Andrikopoulos

Objective: To explore the extent to which the reported unfavorable fatty acid content of abdominal depots in adults is also true for children. In addition, the present study aims to assess the relative importance of abdominal vs buttock adipose tissue fat in the prediction of serum lipid levels in children.Design: A cross-sectional study of children from the island of Crete.Setting: The study was conducted between October 1999 and January 2000 in the Municipality of St Nikolas, Crete.Subjects: A total of 475 children (aged 11–18) participated in the study. Data were obtained on childrens anthropometry, serum lipids, physical activity and abdominal and buttock adipose tissue fatty acids. In total 138 children (aged 11–16) had complete data in all of the variables studied.Results: Abdominal depots have elevated proportions of saturated fatty acids (P<0.001) and trans fatty acids (P<0.001), and reduced proportions of monounsaturated (P<0.001) and polyunsaturated fatty acids (P<0.001) in comparison to buttock depots. Buttock adipose tissue monounsaturated fat correlated negatively to serum LDL-C (P<0.05). Abdominal adipose tissue polyunsaturated fat had negative correlations with serum total cholesterol (P<0.05) and LDL-C (P<0.05). Regression analyses indicated that childrens serum total cholesterol (P<0.05) and LDL-C (P<0.05) were inversely related to abdominal adipose tissue polyunsaturated fat. Body mass index was positively related to serum triglycerides (P<0.01) and LDL-C (P<0.01), and negatively to serum HDL-C (P<0.05). Age was negatively related to serum HDL-C (P<0.05).Conclusions: It appears that, similar to adults, childrens fatty acid composition of abdominal adipose tissue is less favorable than that of the buttock. Abdominal depots have elevated proportions of saturated fatty acids and reduced proportions of monounsaturated and polyunsaturated fat in comparison to buttock depots. Moreover, childrens abdominal depots appear to have higher trans fatty acid contents than buttock depots. Childrens adipose polyunsaturated fat, a biomarker of long-term polyunsaturated fatty acid intake, is inversely related to serum total cholesterol and LDL-C. It appears that abdominal adipose tissue fatty acids are more strongly related to serum lipids than buttock adipose tissue fatty acids. This may be attributed to the reported higher lipolysis rates in abdominal as opposed to buttock depots.Sponsorship: Funding was provided by the Municipality of St Nikolas, Crete, Greece.


Journal of The American College of Nutrition | 1993

Nutrition status of the elderly in Anogia, Crete, Greece

Anthony Kafatos; A Diacatou; D Labadarios; D Kounali; J Apostolaki; J Vlachonikolis; George Mamalakis; S Megremis

General health and nutritional status of 167 free-living elderly Greek (aged 65-91 years) were assessed. The most prevalent diseases/symptoms encountered were related to respiratory, gastrointestinal, musculoskeletal and vascular systems (hypertension). Most subjects were socially active. Body mass index was < 20 and > 25 Kg/m2 in 7 and 57% of the subjects, respectively. Systolic blood pressure was significantly higher in women than in men, and as a group, 18 and 42%, respectively, had diastolic blood pressures > 90 and systolic blood pressures > 160 mmHg. Anemia and hypoalbuminemia were detected in < 5% of the population. Total fat intake was 40-45% of total energy intake and most of it came from monounsaturated fat. Hypercholesterolemia (> 6 mmol/L) was present in 32% of subjects. The percentages of men who smoked (66%) or drank (68%) were significantly higher than those of women (2 and 1%, respectively). Dietary intake data were compared with US recommended dietary allowances (RDA) for elderly. Daily energy and protein intakes were lower than the US RDA levels; calcium intake was > 50% of the US RDA, while magnesium and vitamin B6 levels were < 50% of the US RDA. Vitamin C intake was much higher than that of the US RDA. Mean thiamin, vitamin A, riboflavin and iron intakes were below the US RDA, while fiber intake was < 50% of the corresponding US estimate. Phosphorus was higher than the US RDA in men, while lower for women. Sodium intakes exceeded those recommended, while potassium levels were higher than those recommended in males, and lower in females.(ABSTRACT TRUNCATED AT 250 WORDS)


Annals of Nutrition and Metabolism | 2009

Adipose tissue fatty acids in breast cancer patients versus healthy control women from Crete.

George Mamalakis; Christos M. Hatzis; E. de Bree; Elias Sanidas; Dimitris D. Tsiftsis; J. Askoxylakis; Markos Daskalakis; George Tsibinos; A Kafatos

Background: Few studies have implemented biomarkers of fatty acid intake in relation to breast cancer. Aims: To examine possible differences in adipose tissue fatty acid composition between breast cancer patients and healthy control women. The relationship between tumor promotion and adipose tissue fatty acid synthesis was also investigated. Methods: The study was conducted at the University of Crete. Subjects included 94 women with clinically diagnosed cancer of the breast and 131 healthy control women. Histological tumor grading and breast cancer staging were assessed. Fatty acids were determined by gas chromatography in gluteal adipose tissue. Results: Conditional logistic regression analysis controlling for potential confounders indicated that elevated adipose monounsaturated fatty acids and oleic acid are associated with reduced odds of breast cancer [OR (T2 vs. T1) 0.15; 95% CI 0.03–0.64, and OR (T2 vs. T1) 0.18; 95% CI 0.04–0.71, respectively]. Adipose myristic acid was associated with an increase in breast cancer risk [OR (T3 vs. T1) 5.66; 95% CI 1.3–23.9]. Conclusions: Adipose oleic acid is inversely related, whereas adipose myristic acid is positively related to breast cancer risk. These relations could be mediated by Her-2/neu and FAS oncogenes.

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