It is suggested that nutrient densities are less affected by measurement errors than absolute intake estimates of dietary exposure. We compared the validity of absolute intakes and densities of protein (kJ from protein/total energy (kJ)), potassium, and sodium (potassium or sodium (in mg)/total energy (kJ)) assessed by different dietary assessment methods. For 69 Dutch subjects, two duplicate portions (DPs), five to fifteen 24-h dietary recalls (24 hRs, telephone-based and web-based) and two food frequency questionnaires (FFQs) were collected and compared to duplicate urinary biomarkers and one or two doubly labelled water measurements.
View Article and Find Full Text PDFJ Nutr
December 2018
Background: Methylglyoxal (MGO) is the most potent precursor of advanced glycation end products (AGEs). MGO and AGEs have been associated with diabetes, its complications, and other age-related diseases. Experimental studies have shown that the flavonoids quercetin and epicatechin are able to scavenge MGO and lower AGE formation.
View Article and Find Full Text PDFPLoS One
July 2018
Cocoa consumption has beneficial cardiometabolic effects, but underlying mechanisms remain unclear. Epicatechin, the cocoa major monomeric flavan-3-ol, is considered to contribute to these cardio-protective effects. We investigated effects of pure epicatechin supplementation on gene expression profiles of immune cells in humans.
View Article and Find Full Text PDFScope: Cocoa, rich in flavan-3-ols, improves vascular function, but the contribution of specific flavan-3-ols is unknown. We compared the effects of pure epicatechin, a major cocoa flavan-3-ol, and chocolate.
Methods And Results: In a randomized crossover study, twenty healthy men (40-80 years) were supplemented with: (1) 70g dark chocolate (150 mg epicatechin) with placebo capsules; (2) pure epicatechin capsules (2 × 50 mg epicatechin) with 75g white chocolate; and (3) placebo capsules with 75 g white chocolate (0 mg epicatechin).
High Na and low K intakes have adverse effects on blood pressure, which increases the risk for CVD. The role of endothelial dysfunction and inflammation in this pathophysiological process is not yet clear. In a randomised placebo-controlled cross-over study in untreated (pre)hypertensives, we examined the effects of Na and K supplementation on endothelial function and inflammation.
View Article and Find Full Text PDFAs FFQ are subject to measurement error, associations between self-reported intake by FFQ and outcome measures should be adjusted by correction factors obtained from a validation study. Whether the correction is adequate depends on the characteristics of the reference method used in the validation study. Preferably, reference methods should (1) be unbiased and (2) have uncorrelated errors with those in the FFQ.
View Article and Find Full Text PDFHigh concentrations of plastic debris have been observed in the oceans. Much of the recent concern has focused on microplastics in the marine environment. Recent studies of the size distribution of the plastic debris suggested that continued fragmenting of microplastics into nanosized particles may occur.
View Article and Find Full Text PDFDietary flavonoid intake is associated with reduced risk of cardiovascular diseases, possibly by affecting metabolic health. The relative potency of different flavonoids in causing beneficial effects on energy and lipid metabolism has not been investigated. Effects of quercetin, hesperetin, epicatechin, apigenin and anthocyanins in mice fed a high-fat diet (HF) for 12 weeks were compared, relative to normal-fat diet.
View Article and Find Full Text PDFBackground: 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).
View Article and Find Full Text PDFGiven the positive results of quercetin in in vitro genotoxicity studies, the in vivo genotoxic properties of this important dietary flavonoid warrant testing, especially considering possible high intake via widely available food supplements. Here, this was done by transcriptome analyses of the most relevant tissues, liver and small intestine, of quercetin supplemented mice. Quercetin (0.
View Article and Find Full Text PDFBackground: Isoflavone supplements, consumed by women experiencing menopausal symptoms, are suggested to have positive effects on menopause-related adiposity and cardiovascular disease risk profile, but discussions about their safety are still ongoing.
Objective: The objective was to study the effects of an 8-wk consumption of 2 different isoflavone supplements compared with placebo on whole-genome gene expression in the adipose tissue of postmenopausal women.
Design: This double-blind, randomized, placebo-controlled crossover intervention consisted of 2 substudies, one with a low-genistein (LG) supplement (56% daidzein + daidzin, 16% genistein + genistin, and 28% glycitein + glycitin) and the other with a high-genistein (HG) supplement (49% daidzein + daidzin, 41% genistein + genistin, and 10% glycitein + glycitin).
Arch Biochem Biophys
October 2014
Plant metabolism creates complex mixtures of polyphenols in plant foods. Epidemiology and human trials reduced this complexity, by studying specific foods; subclasses of polyphenols; individual polyphenols, or total antioxidant capacity (TAC). This implies the following assumptions: (1) a limited number of potent polyphenols exists; (2) well-defined natural potent mixtures of polyphenols exist; (3) polyphenols share a common biological activity (e.
View Article and Find Full Text PDFElevated circulating lipid levels are known risk factors for cardiovascular diseases (CVD). In order to examine the effects of quercetin on lipid metabolism, mice received a mild-high-fat diet without (control) or with supplementation of 0.33% (w/w) quercetin for 12 weeks.
View Article and Find Full Text PDFWe report the results of a 28-day oral exposure study in rats, exposed to <20 nm noncoated, or <15 nm PVP-coated silver nanoparticles ([Ag] = 90 mg/kg body weight (bw)), or AgNO(3) ([Ag] = 9 mg/kg bw), or carrier solution only. Dissection was performed at day 29, and after a wash-out period of 1 or 8 weeks. Silver was present in all examined organs with the highest levels in the liver and spleen for all silver treatments.
View Article and Find Full Text PDFCriteria for assessing the purported protection by flavanol-rich foods against vascular dysfunction and oxidative damage to biomolecules was the subject of the 27th Hohenheim Consensus Conference held on July 11, 2011. State-of-the-art evidence was put into perspective, focusing on several questions that were followed by a consensus answer. Among the topics addressed were the major sources of flavanols in the human diet, the bioavailability of flavanols, biomarkers for "health benefit," and the biological function of flavanols.
View Article and Find Full Text PDFFlavonoids are bioactive food compounds with potential lipid-lowering effects. Commercially available enzymatic assays are widely used to determine free fatty acid (FFA) and triglyceride (TG) levels both in vivo in plasma or serum and in vitro in cell culture medium or cell lysate. However, we have observed that various flavonoids interfere with peroxidases used in these enzymatic assays, resulting in incorrect lower FFA and TG levels than actually present.
View Article and Find Full Text PDFHuman studies provide evidence for beneficial effects of polyphenol-rich foods on cardiovascular health. The antioxidant activity of polyphenols potentially explains these effects, but is the antioxidant activity a reliable predictor for these effects? An International Life Sciences Institute Europe working group addressed this question and explored the potential of antioxidant claims for polyphenols in relation to cardiovascular health by using the so-called Process for the Assessment of Scientific Support for Claims on Foods project criteria. In this process, analytical aspects of polyphenols, their occurrence in foods, dietary intake, and bioavailability were reviewed.
View Article and Find Full Text PDFMolecular mechanisms triggered by high dietary beta-carotene (BC) intake in lung are largely unknown. We performed microarray gene expression analysis on lung tissue of BC supplemented beta-carotene 15,15'-monooxygenase 1 knockout (Bcmo1 (-/-)) mice, which are-like humans-able to accumulate BC. Our main observation was that the genes were regulated in an opposite direction in male and female Bcmo1 (-/-) mice by BC.
View Article and Find Full Text PDFFlavonols are strong antioxidants in plant foods and tea is a major dietary source. There is evidence from prospective cohort studies that tea and flavonols are inversely related to stroke incidence. We conducted a metaanalysis of prospective cohort studies to assess quantitatively the strength of the association between flavonol intake and stroke incidence.
View Article and Find Full Text PDFThe vasorelaxing properties of chocolate and wine might relate to the presence of phenolic compounds. One of the potential mechanisms involved is stimulation of endothelial nitric oxide (NO) production, as NO is a major regulator of vasodilatation. This study aimed to develop an in vitro assay using the hybrid human endothelial cell line EA.
View Article and Find Full Text PDFPeanut skins, a byproduct of the peanut butter industry, are a rich source of proanthocyanidins, which might be used in food supplements. Data on the molecular diversity of proanthocyanidins in peanut skins is limited and conflicting with respect to the ratio of double- (A-type) versus single-linked (B-type) flavan-3-ol units. NP- and RP-HPLC-MS were used as tools to analyze the molecular diversity of proanthocyanidins in a 20% (v/v) methanol extract of peanut skins.
View Article and Find Full Text PDFIntervention studies with procyanidin (PC)-rich extracts and products such as cocoa and wine suggest protective effects of PC against cardiovascular diseases. However, there is no consensus on the absorption and metabolism of PC dimers. Interestingly, nothing is known about the absorption of A-type PC.
View Article and Find Full Text PDFProcyanidins (PCs) are highly abundant phenolic compounds in the human diet and might be responsible for the health effects of chocolate and wine. Due to low absorption of intact PCs, microbial metabolism might play an important role. So far, only a few studies, with crude extracts rich in PCs but also containing a multitude of other phenolic compounds, have been performed to reveal human microbial PC metabolites.
View Article and Find Full Text PDFPlant lignans present in foods such as whole grains, seeds and nuts, fruits and vegetables, and beverages. Plant lignans are converted by intestinal bacteria into the enterolignans enterodiol and enterolactone. Up to now, epidemiological evidence for a protective role of enterolignans on cardiovascular diseases is limited and inconsistent.
View Article and Find Full Text PDFAlthough the flavonol quercetin is intensively investigated, our knowledge about its bioavailability and possible target organs is far from being complete. The aim of this study was to check the potential of quercetin to accumulate in various tissues after long-term dietary treatment compared with a single treatment with flavonol. Pigs ingested either a single dose of quercetin aglycone (25 mg/kg body weight; Expt.
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