Antonis Zampelas

Differences in postprandial lipaemic response between Northern and Southern Europeans

Postprandial lipaemic responses to two test meals were investigated in 30 Northern (15 British and 15 Irish), and 30 Southern (Greeks from Crete) healthy male Europeans. The meals were a saturated fatty acid (SFA) meal, which resembled the fatty acid composition of an average UK diet, and a monounsaturated fatty acid (MUFA) meal in which the fat consisted of olive oil. Habitual diets of the two groups differed, with higher total fat, (P < 0.03) and MUFA (P < 0.0001) and lower polyunsaturated fatty acid (PUFA) (P < 0.0001) intakes in Southern than Northern Europeans. Levels of total MUFA (P < 0.02) and oleic acid (P < 0.004) were also higher in adipose tissue of Southern in comparison to Northern Europeans. In both European groups there were no significant differences in postprandial triglyceride response between the two meal types, SFA or MUFA. However, Northern and Southern Europeans showed significant differences in their patterns of postprandial response in plasma triglycerides (P < 0.0001), apolipoprotein B-48 (P < 0.0001), NEFA (P < 0.0001), insulin (P < 0.0007), and factor VII activity (P-0.03). In the case of NEFA, areas under the response curve were higher following the SFA than the MUFA meal for both groups, (P < 0.003) and were greater in Southern than Northern Europeans (P < 0.002) and apo B-48 responses were lower (P < 0.005). Some of these differences may reflect differences in fasting levels since fasting apolipoprotein B-48 levels were lower (P < 0.01) and fasting NEFA (P < 0.02) and insulin (P < 0.005) were higher in the Southern than in the Northern Europeans. In addition, 9 h postprandial post-heparin lipoprotein lipase activity was lower in the Southern than in the Northern Europeans (P < 0.0006). This is the first report of differences in postprandial lipid, factor VII and insulin responses in Southern and Northern Europeans which may be of importance in explaining the different susceptibilities of these two populations to risk of coronary artery disease.

The effect of triacylglycerol fatty acid positional distribution on postprandial plasma metabolite and hormone responses in normal adult men

The present study has examined the possibility that the positional distribution of fatty acids on dietary triacyglycerol (TAG) influences the postprandial response to a liquid meal in adult subjects. Postprandial TAG, non-esterified fatty acids (NEFA), ketones, glucose, insulin and gastric inhibitory polypeptide (GIP) responses were monitored in sixteen normal adult male subjects over 6 h following consumption of test meals containing dietary TAG in which palmitic acid was predominantly on the sn-1 (Control) or sn-2 positions (Betapol). Plasma total TAG, chylomicron-rich TAG and chylomicron-poor TAG concentrations were identical in response to the two test meals. The peak increase (mean (SD)) in chylomicron TAG was 0.85 (0.46) mmol/l after the Control meal and 0.85 (0.42) mmol/l after the Betapol meal. Plasma glucose, insulin, GIP, NEFA and ketone concentrations were also very similar following the two meals. It is concluded that dietary TAG containing saturated fatty acids on the sn-2 position appear in plasma at a similar level and over a similar timescale to TAG in which saturated fatty acids are predominantly located on sn-1 or sn-3 positions. The results reported in the present study demonstrate that the positional distribution of fatty acids on dietary TAG is not an important determinant of postprandial lipaemia in adult male subjects, but do not exclude the possibility that different responses may occur when these dietary TAG are given long term.

The effect of test meal monounsaturated fatty acid: saturated fatty acid ratio on postprandial lipid metabolism

Epidemiological evidence shows that a diet high in monounsaturated fatty acids (MUFA) but low in saturated fatty acids (SFA) is associated with reduced risk of CHD. The hypocholesterolaemic effect of MUFA is known but there has been little research on the effect of test meal MUFA and SFA composition on postprandial lipid metabolism. The present study investigated the effect of meals containing different proportions of MUFA and SFA on postprandial triacylglycerol and non-esterified fatty acid (NEFA) metabolism. Thirty healthy male volunteers consumed three meals containing equal amounts of fat (40 g), but different proportions of MUFA (12, 17 and 24% energy) in random order. Postprandial plasma triacylglycerol, apolipoprotein B-48, cholesterol, HDL-cholesterol, glucose and insulin concentrations and lipoprotein lipase (EC 3.1.1.34) activity were not significantly different following the three meals which varied in their levels of SFA and MUFA. There was a significant difference in the postprandial NEFA response between meals. The incremental area under the curve of postprandial plasma NEFA concentrations was significantly (P = 0.03) lower following the high-MUFA meal. Regression analysis showed that the non-significant difference in fasting NEFA concentrations was the most important factor determining difference between meals, and that the test meal MUFA content had only a minor effect. In conclusion, varying the levels of MUFA and SFA in test meals has little or no effect on postprandial lipid metabolism.

High sodium intake of children through ‘hidden’ food sources and its association with the Mediterranean diet: the GRECO study

Objectives Sodium is the mineral that has been, mainly, linked to hypertension and cardiovascular disease. It is found naturally in many foods, but is also used in the food industry and manufacturing. Identification of total sodium intake, as well as ‘hidden’ sodium intake from food sources early in life is necessary. Methods Four thousand, five hundred and eighty children aged 10–12 years were enrolled, in a cross-sectional, population-based survey. Among other measurements, dietary data were obtained by a semi-quantitative food frequency questionnaire, and sodium intake was calculated. High sodium consumption was considered an intake over 2200 mg/day. Adherence to the Mediterranean dietary pattern was evaluated using the Mediterranean Diet Quality Index for children and adolescent score (KIDMED score). Results Twenty-three percent of Greek children had sodium intake which exceeded the 2200 mg/day recommendation, excluding salt added at table and during cooking. Sodium intake was found elevated in children with moderate and high adherence to the Mediterranean Diet. Additionally, 1 unit increase in KIDMED score (i.e. higher adherence) was associated with 10% [odds ratio (OR) 1.10, 95% confidence interval (CI) 1.07–1.13] increased likelihood of consuming sodium above the median intake (i.e. >1500 mg/day). Thirty-four percent of sodium intake from ‘hidden’ sources came from bread, processed cereals and white cheese. Conclusions Greek children have an elevated sodium intake from ‘hidden’ sources and main contributors are foods which are recommended to be consumed on a daily basis according to the Mediterranean Diet Pyramid. These findings should induce manufacturers to reduce the amount of sodium added during processing of ‘healthy’ foods, especially bread and cheese.

The relationship between dietary habits, blood glucose and insulin levels among people without cardiovascular disease and type 2 diabetes; the ATTICA study.

BACKGROUND Diet has long been associated with a risk of insulin resistance and poor glycemic control. We sought to investigate the association between food groups and indices of glycemic control in adults without type 2 diabetes and cardiovascular disease. METHODS During 2001 - 2002 we randomly enrolled 1514 men (18-87 years old) and 1528 women (18-89 years old) without evidence of cardiovascular disease from the Attica area of Greece. Of them, 118 men and 92 women were excluded from the present analysis due to a history of diabetes mellitus (type 2). Fasting blood glucose and insulin levels were measured, while dietary habits were evaluated through a semi-quantitative food frequency questionnaire. RESULTS Red meat consumption was positively associated with hyperglycemia (p = 0.04), hyperinsulinemia (p = 0.04), and HOMA levels (p = 0.03), even after adjusting for BMI and various other potential confounders. The intake of fruits, vegetables, legumes, yogurt and other dairy products was not associated with levels of glycemic control indices. CONCLUSIONS A higher consumption of red meat and its products may aggravate hyperinsulinemia and insulin resistance in non-diabetic people.

Exaggerated postprandial lipaemia and lower post-heparin lipoprotein lipase activity in middle-aged men.

An exaggerated postprandial lipaemic response is thought to play a central role in the development of an atherogenic lipoprotein phenotype, a recognized lipid risk factor for coronary heart disease. A small number of limited studies have compared postprandial lipaemia in subjects of varying age, but have not investigated mechanisms underlying age-associated changes in postprandial lipaemia. In order to test the hypothesis that impaired lipaemia in older subjects is associated with loss of insulin sensitivity, the present study compared the postprandial lipaemic and hormone responses for 9 h following a standard mixed meal in normolipidaemic healthy young and middle-aged men. Lipoprotein lipase (LPL) and hepatic lipase (HL) activities were determined in post-heparin plasma 9 h postprandially and on another occasion under fasting conditions. Postprandial plasma glucose (P<0.02), retinyl ester (indirect marker for chylomicron particles; P<0.005) and triacylglycerol (TAG)-rich lipoprotein (density<1.006 g/ml fraction of plasma) TAG (P<0.05) and retinyl ester (P<0.005) responses were higher in middle-aged men, whereas plasma insulin responses were lower in this group (P<0.001). Fasting and 9 h postprandial LPL and HL activities were also significantly lower in the middle-aged men compared with the young men (P<0.006). In conclusion, the higher incremental postprandial TAG response in middle-aged men than young men was attributed to the accumulation of dietary-derived TAG-rich lipoproteins (density<1.006 g/ml fraction of plasma) and occurred in the absence of marked differences in fasting TAG levels between the two groups. Fasting and postprandial LPL and HL activities were markedly lower in middle-aged men, but lack of statistical associations between measures of insulin response and post-heparin lipase activities, as well as between insulin and measures of postprandial lipaemia, suggest that this lower activity cannot be attributed to lack of sensitivity of lipases to activation by insulin. Alternatively, post-heparin lipase activities may not be good markers for the insulin-sensitive component of lipase that is activated postprandially.

Development of a diet index for older adults and its relation to cardiovascular disease risk factors: the Elderly Dietary Index.

OBJECTIVE To develop an index that assesses the degree of adherence to nutritional recommendations for older adults (Elderly Dietary Index [EDI]) and investigate its association with risk factors related to cardiovascular disease (CVD). METHODS The EDI was constructed using 10 components (ie, questions about the consumption frequency of meat, fish, fruits, vegetables, grains, legumes, olive oil, and alcohol as well as the type of bread and dairy products) according to the Modified MyPyramid for Older Adults and select features of the traditional Mediterranean diet. Scores from 1 to 4 were assigned to all components of the index. The EDI total score had a range between 10 and 40. As a validation procedure, a sample of 668 elderly individuals without known CVD (the MEDIS Study) was used to evaluate the associations between the proposed index and various health outcomes. RESULTS The overall mean EDI score was 29.2+/-3.5. This score implies that study participants were 73% (ie, 29.2/40) adherent to the nutritional recommendations that the EDI evaluates. Regarding the conventional CVD risk factors, it was found that a 1 unit increase in the EDI score is associated with almost 10% lower odds of being obese or hypertensive or having at least one of the investigated CVD risk factors (P<0.001) after controlling for potential confounders. CONCLUSIONS The suggested EDI may be a useful tool for public health policymakers and other health care professionals to assess diet quality and health status (especially concerning the risk for developing CVD) in older adults.

Dietary and lifestyle patterns in relation to high blood pressure in children: the GRECO study.

Objective: The objective of the present study was to investigate possible associations of dietary patterns with high blood pressure (BP) in a nationwide cross-sectional sample of 10–12 years old Greek schoolchildren. Methods: Anthropometric measurements and information on dietary (by a semi-quantitative food frequency questionnaire) and physical activity habits were obtained from the children. BPs was measured in a single occasion using a standard protocol. Data from 2024 normal energy reporting children were included in the analysis. Principal component analysis was applied to identify dietary patterns. Results: Seven dietary components (patterns) were extracted explaining 55% of the total variation in intake. Multiple logistic regression analysis revealed that predictors of high BP (75th percentile of SBP and/or DBP) were a pattern mainly characterized by the high consumption of cheese and red processed meat [odds ratio (OR) 1.15; 95% confidence intervals (CI) 1.03–1.30], being overweight (OR 2.10; 95% CI 1.61–2.73) or obese (OR 3.84; 95% CI 2.44–6.06) and breakfast frequency (OR 0.95; 95% CI 0.90–0.99). After controlling for sodium intake levels, the dietary pattern did not remain a significant predictor of high BP, indicating the potential mediating effect of sodium in the association. Conclusion: A dietary pattern that is characterized by high cheese and red processed meat consumption increases the likelihood of having high BP in children, probably through increasing dietary sodium intake. These findings could guide future interventions or public health initiatives to prevent the increasing rates of childhood elevated BP levels.

M.611 Epidemiology of overweight and obesity in a Greek adult population; The Attica study

OBJECTIVE To evaluate the status of overweight and obesity in a Greek random sample. RESEARCH METHODS AND PROCEDURES From 2001 to 2002, 1514 men (20 to 87 years old) and 1528 women (20 to 89 years old) were enrolled into the study. Among several sociodemographic, lifestyle, and bioclinical factors, anthropometric characteristics were also recorded. Overweight and obesity were defined according to the World Health Organization classification. RESULTS The prevalences of overweight and obesity were 53% and 20% in men and 31% and 15% in women (p for gender differences < 0.05). The age-adjusted peak prevalence of obesity was observed in men older than 40 years old and women between 50 and 59 years old (Bonferonni alpha < 0.001). Central obesity prevailed in 36% of men and 43% of women (p for gender differences < 0.001). Obesity varied from 10% in rural to 25% in urban areas, but this difference was explained mainly by differences in occupational status (p = 0.9). Moreover, obese and overweight participants were older, less educated, more frequently sedentary, consumed higher quantities of alcoholic beverages, and were devoted to an unhealthier diet as compared with those of normal weight (all p < 0.05). A positive association was also observed between BMI and diastolic and systolic blood pressures, total cholesterol, triglycerides, and glucose levels (all p < 0.001). DISCUSSION Overweight and obesity seem to be a great health problem in the Greek population, especially in middle-aged and older adults. Unfavorable lifestyle habits, low education, and the classical cardiovascular risk factors were associated with the prevalence of these health conditions.

Mediterranean Diet and the Metabolic Syndrome: The Role of Protein

The traditional Mediterranean diet is suggested to be associated with the lowest prevalence of metabolic syndrome, coronary heart disease, and type 2 diabetes and is suggested to be the optimal diet for the general public. This diet is considered to be a moderate protein diet. It has been suggested that the Mediterranean diets protein content is partly responsible for the beneficial effects on health, but the level of protein intake to induce a cardioprotective effect is not yet well known. Nevertheless, there are current studies that support the hypothesis that high protein intake, particularly of plant origin, may have beneficial health effects, which provides some insight on the role of protein in modulating cardiovascular disease risk factors. Therefore, in this work current information about the role of the adoption of the traditional Mediterranean diet on the prevalence of Metabolic Syndrome as a risk factor for coronary heart disease is reviewed. Also special attention is given on the influence of protein intake in relation to the incidence of this syndrome.