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Background and objectives: A cross-sectional observation suggests that total antioxidant capacity (TAC) of the diet positively affects plasma concentrations of [beta]-carotene independent of [beta]-carotene intake. This study was carried out to investigate the effect of two dietary strategies, designed to be comparable in fruits, vegetables, fibre, alcohol and [beta]-carotene intake but substantially different in their TAC, on changes in antioxidant intake and antioxidant status, and in particular in circulating [beta]-carotene concentrations. Subjects: A randomized cross-over intervention trial involving 33 healthy participants and consisting of two 14-day dietary periods (high TAC diet, HT; low TAC diet, LT) with a 14-day washout in between was conducted. Results: Energy, macronutrient, dietary fibre, alcohol and [beta]-carotene intake was not significantly different between LT and HT, whereas intake of other carotenoids and dietary TAC was significantly higher in the HT than in the LT (P Conclusions: The increase in circulating [beta]-carotene along with the increase in dietary TAC suggests that plasma [beta]-carotene could be a marker of TAC intake rather than of [beta]-carotene intake itself. This may explain, in part, why [beta]-carotene supplementation alone has shown no benefit in chronic disease prevention and adds to a putative beneficial role of high dietary TAC diets, which merits further investigation. doi:10.1038/ejcn.2009.46; published online 17 June 2009 Keywords: diet; antioxidants; total antioxidant capacity; [beta]-carotene; intervention study, Introduction Epidemiological evidence supports the strategy of increasing plant food consumption by the general population as a tool for primary prevention against cardiovascular diseases (Gillman et al., 1995; Rimm et [...]

Background and Aims: The high number of negative opinions from the European Food Safety Authority (EFSA) to the requests for authorization of health claims is largely due to the design of human intervention studies, including the inappropriate choice of outcome variables (OVs) and of their methods of measurement (MMs). The present manuscript reports the results of an investigation aimed to collect, collate and critically analyse the information in relation to claimed effects, OVs and MMs, in the context of protection against oxidative damage and cardiovascular health compliant with Regulation 1924/2006.Methods and Results: Claimed effects, OVs and the related MMs were collected from EFSA Guidance documents and applications for authorization of health claims under Articles 13.5 and 14. The OVs and their MMs were evaluated only if the claimed effect was sufficiently defined and was considered beneficial by EFSA. The collection, collation and critical analysis of the relevant scientific literature consisted in the definition of the keywords, the PubMed search strategies and the creation of databases of references. The critical analysis of the OVs and their MMs was performed on the basis of the literature review and was aimed at defining the appropriateness of OVs and MMs in the context of the specific claimed effects.Conclusions: The information provided in this document could serve to EFSA for the development of further guidance on the scientific requirements for health claims, as well as to the stakeholders for the proper design of human intervention studies aimed to substantiate such health claims. [ABSTRACT FROM AUTHOR]

Abstract: Background and aims: Leukocyte telomere length (LTL) is a novel marker of cardiovascular (CV) risk. The aim of the study was to investigate the major determinants of LTL in a healthy young population at very low CV risk. Methods and results: LTL was determined in 82 healthy subjects (49M/33F; age37 ± 9yrs), normotensive and not taking any medication with different family history of cardiovascular disease (CVD) (24yes/58no). Fasting blood samples were drawn in all subjects for the determination of lipid profile, high sensitive C-reactive protein, uric acid, Plasminogen Activator Inhibitor-1 (PAI-1), LTL and Endothelial Progenitor Cell (EPC) number. LTL was assessed with a specific real-time PCR reaction in leukocyte DNA samples. LTL resulted inversely correlated with family history of CVD (t = 2.70; p = 0.009), age (r = −0.238; p = 0.032), waist circumference (r = −0.256; p = 0.02), triglycerides (r = −0.218; p = 0.049), PAI-1 (r = −0.288; p = 0.009) and directly correlated with HDL-cholesterol (r = 0.316; p = 0.004) and EPC number (r = 0.358; p = 0.002). At a multivariate analysis, family history of CVD (p = 0.013), EPC count (p = 0.003), and HDL-cholesterol (p = 0.017) were independently associated with LTL (r = 0.62). Conclusion: LTL is independently associated to CV risk factors also in healthy young adults. [Copyright &y& Elsevier]

Abstract: Background and aims: The study explores the degree of control of hyperglycaemia and cardiovascular (CV) disease risk factors in men and women with type 2 diabetes and the impact thereon of obesity, central adiposity, age and use of medications. Methods and results: A cross-sectional survey was conducted at 10 hospital-based outpatients diabetes clinics. 1297 men and 1168 women with no previous CV events were studied. Women were slightly (only one year) older and more obese than men: average BMI was respectively 30.7 ± 5.7 vs 28.6 ± 4.1 kg/m2 (p < 0.001), and prevalence of abdominal obesity was 86% vs 44% (p < 0.001). Women smoked less, but had higher HbA1c, LDL cholesterol, non-HDL cholesterol, systolic blood pressure and serum fibrinogen than men. Accordingly optimal targets for HbA1c (<7%), LDL cholesterol (<100 mg/dL), HDL cholesterol (>40 for men, >50 for women, mg/dL), and systolic blood pressure (<130 mmHg) were less frequently achieved by women than men (respectively 33.8% vs 40.2%; 14.6% vs 19.2%; 34.1% vs 44.5%; 68.8% vs 72%; p < 0.05 for all). Findings were confirmed after stratification for waist circumference (< or ≥ 88 cm for women; < or ≥ 102 cm for men), BMI (< or ≥ 25 kg/m2) or age (< or ≥ 65 years). As for treatment, women were more likely than men to take insulin, alone or in combination with oral hypoglycaemic drugs, to be under anti-hypertensive treatment, whereas the use of lipid lowering drugs was similar in men and women. Conclusions: Control of hyperglycaemia and major CVD risk factors is less satisfactory in women than men. The gender disparities are not fully explained by the higher prevalence of total and central obesity in women; or by a less intensive medical management in women. [Copyright &y& Elsevier]

Abstract: Macrophages, a heterogeneous and ubiquitous cell population representing up to 15% of the cellular content of different types of tissue, are the principal cell mediators in response to pathogens, inflammation process, tissue homeostasis and repair and play a pivotal role in atherosclerosis and insulin resistance because of their capacity to be the major source of inflammatory cytokines, which can function through paracrine and endocrine mechanisms. Recently, differently activated macrophage populations have been described, depending on a large variety of microenvironmental signals, and it is now recognized that their activation plays a crucial role in the development and progression of atherosclerosis. There is good evidence of the ability of conjugated linoleic acids and polyphenolic compounds to modulate inflammation in experimental models involving macrophages. This observation leaves room to the intriguing hypothesis that macrophage polarization could represent one of the unifying mechanisms through which specific food components can exert anti-inflammatory effects in humans, contributing to the prevention of chronic diseases strongly linked to inflammation, such as atherosclerosis. Future studies should be addressed to substantiate this hypothesis, investigating whether or not physiological concentrations of food-derived metabolites can perturb macrophage activation in vitro. On the in vivo side, the evaluation of macrophage populations in tissues, however complex, should be included among the analyses performed in observational and intervention studies, in order to understand if macrophage activation is involved in the anti-inflammatory activity of a specific dietary regimen. [Copyright &y& Elsevier]

Abstract: Background and aims: Oxidative stress has been advocated as a major cause for cardiovascular disease (CVD), and low plasma antioxidant concentrations are associated with endothelial dysfunction, the first step towards atherosclerosis. However, although the antioxidant content in fruits and vegetables may explain at least in part their protective effect against CVD, supplementation with antioxidant vitamins fails to improve endothelial function and reduce CVD risk. The aim of this study was to investigate the impact of a diet rich in antioxidants on endothelial function measured by flow-mediated dilatation (FMD) in volunteers at low cardiovascular risk. Methods and results: In a crossover trial, 24 subjects (13 women, mean age 61 ± 3 years), received, in a randomised order, a 14-day high (HT) and a 14-day low (LT) antioxidant diets, with a 2-week wash-out (WO) in between. Both diets were comparable in daily portions of fruits and vegetables, and in alcohol, fibre and macronutrient intake, but differed in their total antioxidant capacity. Before and after each diet, anthropometrics, blood pressure, fasting plasma glucose, lipid profile, hepatic enzymes, circulating antioxidant concentrations, high sensitivity C-reactive protein (hs-CRP) and FMD were assessed. FMD increased significantly during the HT diet compared to the LT (p < 0.000). FMD values were 2.3% higher after HT compared with LT (p < 0.001) after adjustment for age, gender and diet order. α-tocopherol increased significantly (p < 0.05) and hs-CRP and of γ-glutamyltranspeptidase decreased significantly (p < 0.05 and p < 0.01, respectively) during the HT diet, compared with the LT diet. Conclusions: A short-term HT diet improves endothelial function in volunteers at low cardiovascular risk, which may further reduce their risk of CVD. [Copyright &y& Elsevier]

Abstract: Background and aims: The number of Endothelial Progenitor Cells (EPCs) is considered a novel marker of cardiovascular (CV) disease. It is not clear which are the main determinants of EPC number in apparently healthy subjects in the absence of overt clinical CV or metabolic abnormalities. We evaluated the main clinical determinants of EPC levels in a population of healthy subjects with normal glucose tolerance. Methods and results: EPC number was determined in 122 healthy subjects (73M/49F;36.6 ± 8yrs). Blood samples were collected to test biochemical variables. OGTT was performed and insulin resistance/compensatory hyperinsulinemia was defined according to fasting plasma insulin (FPI) levels. EPCs were identified as cells co-expressing CD133/CD34/KDR antigens by flow-cytometry. CD133+/KDR+ count inversely correlated with BMI (rho=−0.18;p < 0.05), waist circumference (−0.2;<0.05), diastolic (−0.23;<0.01) and systolic blood pressure (−0.21;<0.05), uric acid (−0.24;<0.005), PAI-1 (−0.197; <0.05) and FPI (−0.2;<0.05) and directly correlated with HDL cholesterol (0.182;<0.05). CD34+/CD133+/KDR+ count inversely correlated with uric acid (−0.28;<0.005) and FPI (−0.2;<0.05). EPC number was lower in males (p < 0.05) and gender was the only independent predictor of EPC count (p < 0.05). By dividing the population in four subgroups based on gender and insulin resistance, CD133+/KDR+ levels were lower in insulin resistant compared to insulin sensitive males (p < 0.05) with no differences in females. Conclusion: The male gender is an independent predictor of low EPC levels in healthy subjects. This might contribute to explaining the higher CV risk in males compared to pre-menopausal age-matched females. In this study a reduced EPC number seems to be associated with insulin resistance in male subjects. [Copyright &y& Elsevier]

Abstract: Background and aims: It has been suggested that lignan intake may decrease the risk for cardiovascular disease (CVD) by modifying traditional risk factors as well as aortic stiffness. However, the role of dietary lignans on the vascular system is largely unknown. The objective was to investigate whether dietary intake of plant lignans in a free-living population was associated with markers of vascular inflammation and function. Methods and Results: We performed a cross-sectional study in 242 (151 males) men and post-menopausal women. Anthropometric characteristics and lignan intake were evaluated. Soluble intercellular adhesion molecule-1 (sICAM-1), insulin, high-sensitive C-reactive protein, glucose, total cholesterol, HDL-cholesterol and triacylglycerols were measured in fasting blood samples. Brachial flow-mediated dilation (FMD) measurements were available for 101 subjects (56 males). Median (interquartile range) daily intake of matairesinol (MAT), secoisolariciresinol (SECO), pinoresinol (PINO), lariciresinol (LARI), and total lignans was 20.9 μg (17.4), 335.3 μg (289.1), 96.7 μg (91.1), 175.7 μg (135.8), and 665.5 μg (413.7), respectively, as assessed by 3-day weighed food record. Plasma concentrations of sICAM-1 (whole sample) significantly decreased (mean (95%CI) = 358 μg/L (320–401), 276 μg/L (252–303), 298 μg/L (271–326), and 269 μg/L (239–303), P per trend 0.013) and FMD values (FMD sub-group) significantly increased (4.1% (2.2–6.0), 5.7% (4.3–7.2), 6.4% (4.9–7.8), and 8.1% (6.3–10.0), P per trend 0.016) across quartiles of energy-adjusted MAT intake, even after adjustment for relevant clinical and dietary variables. Intake of SECO was also inversely related to plasma sICAM-1 (P per trend 0.018), but not to FMD values. No relationship between intake of PINO, LARI or total lignans and either sICAM-1 or FMD values was observed. Conclusions: Higher MAT intakes in the context of a typical Northern Italian diet are associated to lower vascular inflammation and endothelial dysfunction, which could have some implications in CVD prevention. [Copyright &y& Elsevier]

BACKGROUND: It is unknown whether diets with a high dietary total antioxidant capacity (TAC) can modify oxidative stress, low-grade inflammation, or liver dysfunction, all of which are risk factors for type 2 diabetes and cardiovascular disease. OBJECTIVE: We studied the effect of high- and low-TAC (HT and LT, respectively) diets on markers of antioxidant status, systemic inflammation, and liver dysfunction. DESIGN: In a crossover intervention, 33 healthy adults (19 men, 14 women) received the HT and LT diets for 2 wk each. Dietary habits were checked with a 3-d food record during both diet periods and the washout period. RESULTS: Fruit and vegetable, macronutrient, dietary fiber, and alcohol intakes did not differ significantly between the 2 diets, whereas dietary TAC, alpha-tocopherol, and ascorbic acid were significantly (P < 0.001) higher during the HT diet. Plasma alpha-tocopherol rose during the HT and decreased during the LT diet (P < 0.02 for difference) without changes in markers of oxidative stress except plasma malondialdehyde, which decreased unexpectedly during the LT diet (P < 0.05). Plasma high-sensitivity C-reactive protein, alanine aminotransferase, gamma-glutamyltranspeptidase, and alkaline phosphatase concentrations decreased during the HT compared with the LT diet (mean +/- SEM for pre-post changes: -0.72 +/- 0.37 compared with 1.05 +/- 0.60 mg/L, P < 0.01; -1.73 +/- 1.02 compared with 2.33 +/- 2.58 U/L, P < 0.01; -2.12 +/- 1.45 compared with 5.15 +/- 2.98 U/L, P < 0.05; and 1.36 +/- 1.34 compared with 5.06 +/- 2.00 U/L, P < 0.01, respectively). CONCLUSION: Selecting foods according to their TAC markedly affects antioxidant intake and modulates hepatic contribution to systemic inflammation without affecting traditional markers of antioxidant status. Copyright © 2008 American Society for Nutrition [ABSTRACT FROM AUTHOR]

BACKGROUND: Insulin resistance (IR) and liver steatosis (LS) are interlinked metabolic derangements whose prevalence is rapidly increasing, but the effect of dietary carbohydrate quality on LS is unknown. OBJECTIVE: The objective was to describe the relation of IR and LS to total carbohydrate, total dietary fiber, and the glycemic index (GI) and glycemic load of the diet. DESIGN: The study was a cross-sectional evaluation of 247 apparently healthy subjects who had no evidence of viral, toxic, or autoimmune hepatitis and who were unselected for alcohol intake. The homeostasis model assessment index was used as a surrogate measure of IR, and a liver echography was used as a proxy for LS grading. Dietary data were collected by using 3-d food records. Total carbohydrate intake, total dietary fiber, GI, and glycemic load were calculated by using a semiquantitative food-frequency questionnaire concerning the dietary sources of carbohydrates. RESULTS: The prevalence of high-grade LS (HG-LS) increased significantly across quartiles of dietary GI (P for trend < 0.034): HG-LS in the 4th quartile (high GI) was twice that in the first 3 quartiles (low to medium GIs), whereas no relation was observed with total carbohydrates, total dietary fiber, or glycemic load. In insulin-sensitive subjects (first 3 quartiles of homeostasis model assessment index of IR), the prevalence of HG-LS did not differ significantly between GI groups, but, in insulin-resistant subjects (4th quartile of homeostasis model assessment index of IR), it was twice as high in those with high GI as in those with low to medium GIs (P = 0.005). CONCLUSIONS: High-GI dietary habits are associated with HG-LS, particularly in insulin-resistant subjects. Dietary advice on the quality of carbohydrate sources therefore may be a complementary tool for preventing or treating LS of metabolic origin. Copyright © 2006 American Society for Nutrition [ABSTRACT FROM AUTHOR]

Describes a study of the relation of serum insulin levels to plasma lipid levels and blood pressure in two groups of healthy subjects with normal glucose tolerance. Methods of study; Results; Conclusions.