After the discovery that trans fat increases the risk of coronary heart disease, trans fat content of foods have considerably changed. The aim of this study was to systematically review available ...data on intakes of trans fat and its dietary sources in general populations worldwide. Data from national dietary surveys and population studies published from 1995 onward were searched via Scopus and websites of national public health institutes. Relevant data from 29 countries were identified. The most up to date estimates of total trans fat intake ranged from 0.3 to 4.2 percent of total energy intake (En%) across countries. Seven countries had trans fat intakes higher than the World Health Organization recommendation of 1 En%. In 16 out of 21 countries with data on dietary sources, intakes of trans fat from animal sources were higher than that from industrial sources. Time trend data from 20 countries showed substantial declines in industrial trans fat intake since 1995. In conclusion, nowadays, in the majority of countries for which data are available, average trans fat intake is lower than the recommended maximum intake of 1 En%, with intakes from animal sources being higher than from industrial sources. In the past 20 years, substantial reductions in industrial trans fat have been achieved in many countries.
Background: Prospective cohort studies showed inverse associations between the intake of flavonoid-rich foods (cocoa and tea) and cardiovascular disease (CVD). Intervention studies showed protective ...effects on intermediate markers of CVD. This may be due to the protective effects of the flavonoids epicatechin (in cocoa and tea) and quercetin (in tea). Objective: We investigated the effects of supplementation of pure epicatechin and quercetin on vascular function and cardiometabolic health. Design: Thirty-seven apparently healthy men and women aged 40–80 y with a systolic blood pressure (BP) between 125 and 160 mm Hg at screening were enrolled in a randomized, double-blind, placebo-controlled, crossover trial. CVD risk factors were measured before and after 4 wk of daily flavonoid supplementation. Participants received (−)-epicatechin (100 mg/d), quercetin-3-glucoside (160 mg/d), or placebo capsules for 4 wk in random order. The primary outcome was the change in flow-mediated dilation from pre- to postintervention. Secondary outcomes included other markers of CVD risk and vascular function. Results: Epicatechin supplementation did not change flow-mediated dilation significantly (1.1% absolute; 95% CI: −0.1%, 2.3%; P = 0.07). Epicatechin supplementation improved fasting plasma insulin (Δ insulin: −1.46 mU/L; 95% CI: −2.74, −0.18 mU/L; P = 0.03) and insulin resistance (Δ homeostasis model assessment of insulin resistance: −0.38; 95% CI: −0.74, −0.01; P = 0.04) and had no effect on fasting plasma glucose. Epicatechin did not change BP (office BP and 24-h ambulatory BP), arterial stiffness, nitric oxide, endothelin 1, or blood lipid profile. Quercetin-3-glucoside supplementation had no effect on flow-mediated dilation, insulin resistance, or other CVD risk factors. Conclusions: Our results suggest that epicatechin may in part contribute to the cardioprotective effects of cocoa and tea by improving insulin resistance. It is unlikely that quercetin plays an important role in the cardioprotective effects of tea. This study was registered at clinicaltrials.gov as NCT01691404.
Endothelial dysfunction is involved in the development of atherosclerosis, which precedes asymptomatic structural vascular alterations as well as clinical manifestations of cardiovascular disease ...(CVD). Endothelial function can be assessed non-invasively using the flow-mediated dilation (FMD) technique. Flow-mediated dilation represents an endothelium-dependent, largely nitric oxide (NO)-mediated dilatation of conduit arteries in response to an imposed increase in blood flow and shear stress. Flow-mediated dilation is affected by cardiovascular (CV) risk factors, relates to coronary artery endothelial function, and independently predicts CVD outcome. Accordingly, FMD is a tool for examining the pathophysiology of CVD and possibly identifying subjects at increased risk for future CV events. Moreover, it has merit in examining the acute and long-term impact of physiological and pharmacological interventions in humans. Despite concerns about its reproducibility, the available evidence shows that highly reliable FMD measurements can be achieved when specialized laboratories follow standardized protocols. For this purpose, updated expert consensus guidelines for the performance of FMD are presented, which are based on critical appraisal of novel technical approaches, development of analysis software, and studies exploring the physiological principles underlying the technique. Uniformity in FMD performance will (i) improve comparability between studies, (ii) contribute to construction of reference values, and (iii) offer an easy accessible and early marker of atherosclerosis that could complement clinical symptoms of structural arterial disease and facilitate early diagnosis and prediction of CVD outcomes.
Tea consumption is associated with a lower risk of cardiovascular disease including stroke. Direct effects of tea components on the vasculature, particularly the endothelium, may partly explain this ...association.
We performed a meta-analysis of controlled human intervention studies on the effect of tea on flow-mediated dilation (FMD) of the brachial artery, a measurement of endothelial function, which is suggested to be associated with cardiovascular risk.
Human intervention studies were identified by systematic search of the databases Medline, Embase, Chemical Abstracts and Biosis through March 2009 and by hand-searching related articles. Studies were selected based on predefined criteria: intervention with tea as the sole experimental variable, placebo-controlled design, and no missing data on FMD outcome or its variability. A random effects model was used to calculate the pooled overall effect on FMD due to the intake of tea. The impact of various subject and treatment characteristics was investigated in the presence of heterogeneity.
In total, 9 studies from different research groups were included with 15 relevant study arms. The overall absolute increase in FMD of tea vs. placebo was 2.6% of the arterial diameter (95% CI: 1.8-3.3%; P-value <0.001) for a median daily dose of 500 mL of tea (2-3 cups). This is a relative increase of approximately 40% compared to the average FMD of 6.3% measured under placebo or baseline conditions. There was significant heterogeneity between studies (P-value <0.001) that might partly be explained by the cuff position either distal or proximal to the area of FMD measurement. No indication for publication bias was found.
Moderate consumption of tea substantially enhances endothelial-dependent vasodilation. This may provide a mechanistic explanation for the reduced risk of cardiovascular events and stroke observed among tea drinkers.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract Background Flow-mediated dilation (FMD) is an accepted technique to quantify endothelial function and has shown to have prognostic value for future cardiovascular disease (CVD). The ...predictive strength of FMD in CVD patients compared to populations not diagnosed for CVD warrants further investigation. We systematically reviewed prospective studies that investigated the association between brachial FMD and future cardiovascular events, with particular focus on the role of underlying health status. Methods To obtain eligible studies, several literature databases were systematically searched through March 2011. Pooled overall risk estimates were calculated separately for continuous risk estimates for CVD (per 1% higher FMD) and for categorical risk estimates for CVD (having high vs. low FMD), based on random-effects models. Results A total of 23 studies including 14,753 subjects were eligible for inclusion in the meta-analysis. For studies reporting continuous risk estimates, the pooled overall CVD risk was 0.92 (95%CI: 0.88; 0.95) per 1% higher FMD. The observed association seemed stronger (P-value < 0.01) in diseased populations than in asymptomatic populations (0.87 (95%CI: 0.83; 0.92) and 0.96 (95%CI: 0.92; 1.00) per 1% higher FMD, respectively). For studies reporting categorical risk estimates, the pooled overall CVD risk for high vs. low FMD was similar in both types of populations, on average 0.49 (95%CI: 0.39; 0.62). Conclusions Our findings show that brachial FMD is inversely associated with future CVD events, with some indications for a stronger relation in diseased populations. Endothelial dysfunction may be considered relevant for classifying subjects in terms of CVD risk.
Objectives To investigate the association between long term intake of individual saturated fatty acids (SFAs) and the risk of coronary heart disease, in two large cohort studies. Design Prospective, ...longitudinal cohort study.Setting Health professionals in the United States.Participants 73 147 women in the Nurses’ Health Study (1984-2012) and 42 635 men in the Health Professionals Follow-up Study (1986-2010), who were free of major chronic diseases at baseline.Main outcome measure Incidence of coronary heart disease (n=7035) was self-reported, and related deaths were identified by searching National Death Index or through report of next of kin or postal authority. Cases were confirmed by medical records review.Results Mean intake of SFAs accounted for 9.0-11.3% energy intake over time, and was mainly composed of lauric acid (12:0), myristic acid (14:0), palmitic acid (16:0), and stearic acid (18:0; 8.8-10.7% energy). Intake of 12:0, 14:0, 16:0 and 18:0 were highly correlated, with Spearman correlation coefficients between 0.38 and 0.93 (all P<0.001). Comparing the highest to the lowest groups of individual SFA intakes, hazard ratios of coronary heart disease were 1.07 (95% confidence interval 0.99 to 1.15; Ptrend=0.05) for 12:0, 1.13 (1.05 to 1.22; Ptrend<0.001) for 14:0, 1.18 (1.09 to 1.27; Ptrend<0.001) for 16:0, 1.18 (1.09 to 1.28; Ptrend<0.001) for 18:0, and 1.18 (1.09 to 1.28; Ptrend<0.001) for all four SFAs combined (12:0-18:0), after multivariate adjustment of lifestyle factors and total energy intake. Hazard ratios of coronary heart disease for isocaloric replacement of 1% energy from 12:0-18:0 were 0.92 (95% confidence interval 0.89 to 0.96; P<0.001) for polyunsaturated fat, 0.95 (0.90 to 1.01; P=0.08) for monounsaturated fat, 0.94 (0.91 to 0.97; P<0.001) for whole grain carbohydrates, and 0.93 (0.89 to 0.97; P=0.001) for plant proteins. For individual SFAs, the lowest risk of coronary heart disease was observed when the most abundant SFA, 16:0, was replaced. Hazard ratios of coronary heart disease for replacing 1% energy from 16:0 were 0.88 (95% confidence interval 0.81 to 0.96; P=0.002) for polyunsaturated fat, 0.92 (0.83 to 1.02; P=0.10) for monounsaturated fat, 0.90 (0.83 to 0.97; P=0.01) for whole grain carbohydrates, and 0.89 (0.82 to 0.97; P=0.01) for plant proteins.Conclusions Higher dietary intakes of major SFAs are associated with an increased risk of coronary heart disease. Owing to similar associations and high correlations among individual SFAs, dietary recommendations for the prevention of coronary heart disease should continue to focus on replacing total saturated fat with more healthy sources of energy.
Background: The effects of dietary fats on the risk of coronary artery disease (CAD) have traditionally been estimated from their effects on LDL cholesterol. Fats, however, also affect HDL ...cholesterol, and the ratio of total to HDL cholesterol is a more specific marker of CAD than is LDL cholesterol. Objective: The objective was to evaluate the effects of individual fatty acids on the ratis of total to HDL cholesterol and on serum lipoproteins. Design: We performed a meta-analysis of 60 selected trials and calculated the effects of the amount and type of fat on total:HDL cholesterol and on other lipids. Results: The ratio did not change if carbohydrates replaced saturated fatty acids, but it decreased if cis unsaturated fatty acids replaced saturated fatty acids. The effect on total:HDL cholesterol of replacing trans fatty acids with a mix of carbohydrates and cis unsaturated fatty acids was almost twice as large as that of replacing saturated fatty acids. Lauric acid greatly increased total cholesterol, but much of its effect was on HDL cholesterol. Consequently, oils rich in lauric acid decreased the ratio of total to HDL cholesterol. Myristic and palmitic acids had little effect on the ratio, and stearic acid reduced the ratio slightly. Replacing fats with carbohydrates increased fasting triacylglycerol concentrations. Conclusions: The effects of dietary fats on total:HDL cholesterol may differ markedly from their effects on LDL. The effects of fats on these risk markers should not in themselves be considered to reflect changes in risk but should be confirmed by prospective observational studies or clinical trials. By that standard, risk is reduced most effectively when trans fatty acids and saturated fatty acids are replaced with cis unsaturated fatty acids. The effects of carbohydrates and of lauric acid-rich fats on CAD risk remain uncertain.
Monounsaturated fatty acids (MUFAs) improve blood lipid profiles in intervention studies, but prospective evidence with regard to MUFA intake and coronary heart disease (CHD) risk is limited and ...controversial.
We investigated the associations of cis MUFA intake from plant (MUFA-P) and animal (MUFA-A) sources with CHD risk separately among 63,442 women from the Nurses’ Health Study (1990–2012) and 29,942 men from the Health Professionals Follow-Up Study (1990–2012).
Intakes of MUFA-Ps and MUFA-As were calculated by using validated food-frequency questionnaires collected every 4 y. Incident nonfatal myocardial infarction and fatal CHD cases (n = 4419) were confirmed by medical record review.
During follow-up, MUFA-Ps and MUFA-As contributed 5.8–7.9% and 4.2–5.4% of energy on average, respectively. When MUFA-Ps were modeled to isocalorically replace other macronutrients, HRs (95% CIs) of CHD were 0.83 (0.68, 1.00) for saturated fatty acids (SFAs; 5% of energy), 0.86 (0.76, 0.97) for refined carbohydrates (5% of energy), and 0.80 (0.70, 0.91) for trans fats (2% of energy) (P = 0.05, 0.01, and 0.001, respectively). For MUFA-As, corresponding HRs (95% CIs) for the same isocaloric substitutions were 1.04 (0.79, 1.38) for SFAs, 1.11 (0.91, 1.35) for refined carbohydrates, and 0.88 (0.77, 1.01) for trans fats (P = 0.76, 0.31, and 0.08, respectively). Given the common food sources of SFAs and MUFA-As (Spearman correlation coefficients of 0.81–0.83 between these groups of fatty acids), we further estimated CHD risk when the sum of MUFA-As and SFAs (5% of energy) was replaced by MUFA-Ps, and found that the HR was 0.81 (95% CI: 0.73, 0.90; P < 0.001) for this replacement.
The largely different associations of MUFA-Ps and MUFA-As with CHD risk suggest that plant-based foods are the preferable sources of MUFAs for CHD prevention. These findings are observational and warrant confirmation in intervention settings. This study was registered at clinicaltrials.gov as NCT00005152 and NCT00005182.
Epidemiological evidence has linked consumption of black tea, produced from Camellia sinensis, with a reduced risk of cardiovascular diseases. However, intervention studies on the effects of tea ...consumption on blood pressure (BP) have reported inconsistent results. Our objective was to conduct a systematic literature review with meta-analysis of controlled human intervention studies examining the effect of tea consumption on BP.
We systematically searched Medline, Biosis, Chemical Abstracts and EMBASE databases through July 2013. For inclusion, studies had to meet the following pre-defined criteria: 1) placebo controlled design in human adults, 2) minimum of 1 week black tea consumption as the sole intervention, 3) reported effects on systolic BP (SBP) or diastolic BP (DBP) or both. A random effects model was used to calculate the pooled overall effect of black tea on BP.
Eleven studies (12 intervention arms, 378 subjects, dose of 4-5 cups of tea) met our inclusion criteria. The pooled mean effect of regular tea ingestion was -1.8 mmHg (95% CI: -2.8, -0.7; P = 0.0013) for SBP and -1.3 mmHg (95% CI: -1.8, -0.8; P<0.0001) for DBP. In covariate analyses, we found that the method of tea preparation (tea extract powders versus leaf tea), baseline SBP and DBP, and the quality score of the study affected the effect size of the tea intervention (all P<0.05). No evidence of publication bias could be detected.
Our meta-analysis indicates that regular consumption of black tea can reduce BP. Although the effect is small, such effects could be important for cardiovascular health at population level.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The development of food‐based dietary guidelines for prevention of cardiovascular diseases requires knowledge of the contribution of common foods to SFA and PUFA intake. We systematically reviewed ...available data from European countries on population intakes and dietary sources of total fat, SFA, and PUFA. Data from national dietary surveys or population studies published >1995 were searched through Medline, Web of Science, and websites of national public health institutes. Mean population intakes were compared with FAO/WHO dietary recommendations, and contributions of major food groups to overall intakes of fat and fatty acids were calculated. Fatty acid intake data from 24 European countries were included. Reported mean intakes ranged from 28.5 to 46.2% of total energy (%E) for total fat, from 8.9 to 15.5%E for SFA, from 3.9 to 11.3%E for PUFA. The mean intakes met the recommendation for total fat (20–35%E) in 15 countries, and for SFA (<10%E) in two countries, and for PUFA (6–11%E) in 15 of the 24 countries. The main three dietary sources of total fat and SFA were dairy, added fats and oils, and meat and meat products. The majority of PUFA in the diet was provided by added fats and oils, followed by cereals and cereal products, and meat and meat products. Practical applications: While many European countries meet the recommended intake levels for total fat and PUFA, a large majority of European population exceeds the widely recommended maximum 10%E for SFA. In particular animal based products, such as dairy, animal fats, and fatty meat contribute to SFA intake. Adhering to food‐based dietary guidelines for prevention of CHD and other chronic diseases in Europe, including eating less fatty meats, low‐fat instead of full‐fat dairy, and more vegetable fats and oils will help to reduce SFA intake and at the same time increase PUFA intake. In European countries, SFA intakes are generally higher than the recommended <10%E and PUFA intakes lower than the recommended 6–11%E. Adhering to food‐based dietary guidelines for prevention of CHD and other chronic diseases including eating leaner variants of meat and dairy, and more vegetable fats and oils will help to decrease SFA intake and increase PUFA intake.
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