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Background and aims Atherosclerosis is associated with a reduction in the bioavailability and/or bioactivity of endogenous nitric oxide (NO). Dietary nitrate has been proposed as an alternate source when endogenous NO production is reduced. Our previous study demonstrated a protective effect of dietary nitrate on the development of atherosclerosis in the apoE−/− mouse model. However most patients do not present clinically until well after the disease is established. The aims of this study were to determine whether chronic dietary nitrate supplementation can prevent or reverse the progression of atherosclerosis after disease is already established, as well as to explore the underlying mechanism of these cardiovascular protective effects. Methods 60 apoE−/− mice were given a high fat diet (HFD) for 12 weeks to allow for the development of atherosclerosis. The mice were then randomized to (i) control group (HFD + 1 mmol/kg/day NaCl), (ii) moderate-dose group (HFD +1 mmol/kg/day NaNO3), or (iii) high-dose group (HFD + 10 mmol/kg/day NaNO3) (20/group) for a further 12 weeks. A group of apoE−/− mice (n = 20) consumed a normal laboratory chow diet for 24 weeks and were included as a reference group. Results Long-term supplementation with high dose nitrate resulted in ~ 50% reduction in plaque lesion area. Collagen expression and smooth muscle accumulation were increased, and lipid deposition and macrophage accumulation were reduced within atherosclerotic plaques of mice supplemented with high dose nitrate. These changes were associated with an increase in nitrite reductase as well as activation of the endogenous eNOS-NO pathway. Conclusion Long-term high dose nitrate significantly attenuated the progression of established atherosclerosis in the apoE−/− mice fed a HFD. This appears to be mediated in part through a XOR-dependent reduction of nitrate to NO, as well as enhanced eNOS activation via increased Akt and eNOS phosphorylation.

Background/Objectives Few studies have investigated the association between dietary flavonoid intake, including all major subclasses, and the long-term risk of ischemic heart disease (IHD). We examined whether dietary flavonoid intake associated with IHD incidence, assessing the possible modifying role of sex and smoking, in participants from the Danish Diet, Cancer, and Health study. Subjects/Methods In a cohort study design, 54,496 adults (46.8% male), aged 50–64 years, without a history of IHD, were followed for up to 23 years. Habitual dietary flavonoid intake was estimated from food frequency questionnaires using Phenol-Explorer. Incident cases of IHD were identified within Danish nationwide health registries. Restricted cubic splines in Cox proportional hazards models were used to examine associations between flavonoid intake and IHD risk. Results During follow-up, 5560 IHD events were recorded. No overall association was seen between total flavonoid intake, nor any subclass, and IHD, following adjustment for demographics, lifestyle, and dietary confounders. Stratified by sex and smoking status, higher intakes of specific subclasses associated with lower IHD risk among ever-smokers [Q5 vs. Q1 flavonols HR (95% CI): 0.90 (0.82, 0.99); flavanol oligo+polymers: 0.88 (0.80, 0.97)], but not among never-smokers, nor either sex specifically. Conclusions While we did not find clear evidence that higher habitual dietary flavonoid intake was associated with lower IHD risk, these results do not exclude the possibility that certain subclasses may have a protective role in prevention of IHD among population sub-groups; this was evident among smokers, who are at a higher risk of atherosclerosis.

Flavonoids have shown anti-hypertensive and anti-atherosclerotic properties: the impact of habitual flavonoid intake on vascular function, central haemodynamics and arterial stiffness may be important. We investigated the relationship between habitual flavonoid consumption and measures of central blood pressure and arterial stiffness. We performed cross-sectional analysis of 381 non-smoking healthy older adults (mean age 66·0 (sd 4·1) years; BMI, 26·4 (sd 4·41) kg/m2; 41 % male) recruited as part of the Australian Research Council Longevity Intervention study. Flavonoid intake (i.e. flavonols, flavones, flavanones, anthocyanins, isoflavones, flavan-3-ol monomers, proanthocyanidins, theaflavins/thearubigins and total consumption) was estimated from FFQ using the US Department of Agriculture food composition databases. Measures of central haemodynamics and arterial stiffness included systolic blood pressure (cSBP), diastolic blood pressure (cDBP), mean arterial pressure (cMAP) and augmentation index (cAIx). After adjusting for demographic and lifestyle confounders, each sd/d higher intake of anthocyanins ((sd 44·3) mg/d) was associated with significantly lower cDBP (−1·56 mmHg, 95 % CI −2·65, −0·48) and cMAP (−1·62 mmHg, 95 % CI −2·82, −0·41). Similarly, each sd/d higher intake of flavanones ((sd 19·5) mg/d) was associated with ~1 % lower cAIx (−0·93 %, 95 % CI −1·77, −0·09). These associations remained significant after additional adjustment for (1) a dietary quality score and (2) other major nutrients that may affect blood pressure or arterial stiffness (i.e. Na, K, Ca, Mg, n-3, total protein and fibre). This study suggests a possible benefit of dietary anthocyanin and flavanone intake on central haemodynamics and arterial stiffness; these findings require corroboration in further research.

Introduction Higher flavonoid intakes are beneficially associated with pulmonary function parameters;however, their association with chronic obstructive pulmonary disease (COPD) is unknown. This studyaimed to examine associations between intakes of 1) total flavonoids, 2) flavonoid subclasses and 3) majorflavonoid compounds with incident COPD in participants from the Danish Diet, Cancer and Health study.Methods This prospective cohort included 55 413 men and women without COPD, aged 50–65 years atrecruitment. Habitual flavonoid intakes at baseline were estimated from a food frequency questionnaireusing Phenol-Explorer. Danish nationwide registers were used to identify incident cases of COPD.Associations were modelled using restricted cubic splines within Cox proportional hazards models.Results During 23 years of follow-up, 5557 participants were diagnosed with COPD. Of these, 4013 werecurrent smokers, 1062 were former smokers and 482 were never-smokers. After multivariable adjustments,participants with the highest total flavonoid intakes had a 20% lower risk of COPD than those with thelowest intakes (quintile 5 versus quintile 1: HR 0.80, 95% CI 0.74–0.87); a 6–22% lower risk wasobserved for each flavonoid subclass. The inverse association between total flavonoid intake and COPDwas present in both men and women but only in current smokers (HR 0.77, 95% CI 0.70–0.84) andformer smokers (HR 0.82, 95% CI 0.69–0.97), not never-smokers. Furthermore, higher flavonoid intakesappeared to lessen, but not negate, the higher risk of COPD associated with smoking intensity.Conclusion Dietary flavonoids may be important for partially mitigating the risk of smoking-relatedCOPD. However, smoking cessation should remain the highest priority Introduction Higher flavonoid intakes are beneficially associated with pulmonary function parameters; however, their association with chronic obstructive pulmonary disease (COPD) is unknown. This study aimed to examine associations between intakes of 1) total flavonoids, 2) flavonoid subclasses and 3) major flavonoid compounds with incident COPD in participants from the Danish Diet, Cancer and Health study.Methods This prospective cohort included 55 413 men and women without COPD, aged 50-65 years at recruitment. Habitual flavonoid intakes at baseline were estimated from a food frequency questionnaire using Phenol-Explorer. Danish nationwide registers were used to identify incident cases of COPD. Associations were modelled using restricted cubic splines within Cox proportional hazards models.Results During 23 years of follow-up, 5557 participants were diagnosed with COPD. Of these, 4013 were current smokers, 1062 were former smokers and 482 were never-smokers. After multivariable adjustments, participants with the highest total flavonoid intakes had a 20% lower risk of COPD than those with the lowest intakes (quintile 5 versus quintile 1: HR 0.80, 95% CI 0.74-0.87); a 6-22% lower risk was observed for each flavonoid subclass. The inverse association between total flavonoid intake and COPD was present in both men and women but only in current smokers (HR 0.77, 95% CI 0.70-0.84) and former smokers (HR 0.82, 95% CI 0.69-0.97), not never-smokers. Furthermore, higher flavonoid intakes appeared to lessen, but not negate, the higher risk of COPD associated with smoking intensity.Conclusion Dietary flavonoids may be important for partially mitigating the risk of smoking-related COPD. However, smoking cessation should remain the highest priority.

Accentuated blood pressure (BP) fluctuation and low cerebral blood flow (CBF) response to CO2 increase the risk of transient ischemic attack (TIA) recurrence and stroke in TIA patients. Improving cardio- and cerebrovascular function may reduce stroke risk. We found dietary nitrate lowered dynamic blood pressure variability (BPV) in rats and improved cerebrovascular CO2 reactivity in healthy individuals. In 30 TIA patients, we examined the effects of a 7-day supplementation of dietary nitrate (0.1 mmol·kg-1·day-1) on cerebrovascular function using a randomized, single-blinded, placebo-controlled study design. We hypothesized that 7-day dietary nitrate supplementation would decrease variabilities in BP and CBF and improve CBF-CO2 slope and cerebral autoregulation (CA). We assessed beat-to-beat middle cerebral artery blood velocity (MCAv; index of CBF) and BP at rest and during CO2 breathing. Transfer function analysis was performed on beat-to-beat MCAv and BP to determine CA parameters (gain, phase, and coherence). Irrespective of treatment, high- and low-frequency BP-MCAv gain and MCAv-CO2 slope increased 7 days following TIA onset, while low-frequency BPV decreased (P 0.05). Concurrent with standard treatment, dietary nitrate supplementation reduces BP and CBF fluctuation and improves cerebral autoregulation in TIA patients, without affecting cerebrovascular CO2 reactivity.NEW & NOTEWORTHY We found dietary nitrate supplementation reduced blood pressure and brain blood flow fluctuations and improved the relationship between blood pressure and brain blood flow in transient ischemic attack patients. Meanwhile, dietary nitrate had no effects on the brain blood vessels' response to CO2. We attribute the improved brain blood flow stability to the improved myogenic control of blood pressure with dietary nitrate. Our findings indicate that dietary nitrate could be an effective strategy for stabilizing blood pressure and brain blood flow following transient ischemic attack.

Scope Nitrate and nitrite are approved food additives in some animal-based food products. However, nitrate and nitrite in foods are strictly regulated due to health concerns over methaemoglobinaemia and the potential formation of carcinogenic nitrosamines. In contrast, plants (like leafy vegetables) naturally accumulate nitrate ions; a growing body of research reveals beneficial metabolic effects of nitrate via its endogenous conversion to nitric oxide. To refine the association of dietary nitrate and nitrite intake with health outcomes, reliable measures of nitrate and nitrite intake from dietary food records are required. While a vegetable nitrate content database has been developed, there is a need for a comprehensive up-to-date nitrate and nitrite content database of animal-based foods. Methods and results A systematic literature search (1980 - September 2020) on the nitrate and nitrite content of animal-based foods was carried out. Nitrate and nitrite concentration data and other relevant information were extracted and compiled into a database. The database contains 1921 entries for nitrate and 2077 for nitrite, extracted from 193 publications. The highest median nitrate content was observed in chorizo (median [IQR]; 101.61 [60.05 - 105.93] mg/kg). Canned fish products had the highest median nitrite level (median [IQR]; 20.32 [6.16 - 30.16] mg/kg). By subgroup, the median nitrate value in industrial processed meat products (e.g., uncured burger, patties and sausages), whole milk powder and in particular red meat were higher than cured meat products. Processed meat products from high-income regions had lower median nitrate and nitrite content than those of middle-income regions. Conclusion This database can now be used to investigate the associations between nitrate and nitrite dietary intake and health outcomes in clinical trials and observational studies. This article is protected by copyright. All rights reserved.

An up-to-date nitrate food composition database of plant-based foods is lacking. Such a resource is imperative to obtain a robust assessment of dietary nitrate intakes and facilitate more empirical evaluation of health implications. We updated and expanded our 2017 vegetable nitrate database by including data published between 2016 and 2021, and data on fruits, cereals, herbs, spices, pulses and nuts (1980 - 2021). Of the collated nitrate contents for 264 plant-based foods from 64 countries, 120 were obtained from three or more references. Despite substantial variations, leaf vegetables were the top nitrate-containing foods, followed by stemshoot vegetables, herbs and spices, root vegetables, flower vegetables, tuber vegetables, nuts, fruit vegetables, legume/seed vegetables, fruits and cereals. Banana and strawberry contained far higher amounts of nitrate than previously recognised. In conjunction with the recent animal-based food nitratenitrite database, this database can now be used to evaluate dietary nitrate intake in clinical and epidemiological studies.

Background Flavonoid-rich foods may contribute to a lower risk of ischemic stroke through their anti-inflammatory, anti-atherogenic, and anti-thrombotic properties. We aimed to examine the relationship between flavonoid intake and ischemic stroke incidence in participants from the Danish Diet, Cancer, and Health study. Methods In this prospective cohort study, 55,169 Danish citizens without a prior ischemic stroke (median [IQR] age at enrolment of 56 [52 – 60] years), were followed for 21 [20 – 22] years. Baseline flavonoid intake was estimated from food frequency questionnaires using the Phenol-Explorer database. Incident cases of stroke were identified from Danish nation-wide public health registries. Associations between quintiles of flavonoid intake and incident ischemic stroke were assessed using Cox proportional hazard models adjusting for age, sex, BMI, smoking status, physical activity, alcohol intake, education, and income. Results During follow-up, 4,317 individuals experienced an ischemic stroke. Compared to participants in quintile one and after multivariable adjustments, those in quintile five for intake of total flavonoids, flavonols and oligo+polymers had a 12% [HR (95% CI): 0.88 (0.81, 0.96)], 10% [0.90 (0.82, 0.98)], and 18% [0.82 (0.75, 0.89)], lower risk of ischemic stroke incidence, respectively. Intake of flavan-3-ol monomers, anthocyanins, flavanones and flavones were not associated with incident ischemic stroke. Conclusions A moderate habitual intake of flavonoids, in particular the flavonol and flavan-3-ol oligo+polymer subclasses, is associated with a lower risk of ischemic stroke. Key messages Flavonoid rich foods appear protective against ischemic stroke.

Whether the vascular effects of inorganic nitrate, observed in clinical trials, translate to a reduction in cardiovascular disease (CVD) with habitual dietary nitrate intake in prospective studies warrants investigation. We aimed to determine if vegetable nitrate, the major dietary nitrate source, is associated with lower blood pressure (BP) and lower risk of incident CVD. Among 53,150 participants of the Danish Diet, Cancer, and Health Study, without CVD at baseline, vegetable nitrate intake was assessed using a comprehensive vegetable nitrate database. Hazard ratios (HRs) were calculated using restricted cubic splines based on multivariable-adjusted Cox proportional hazards models. During 23 years of follow-up, 14,088 cases of incident CVD were recorded. Participants in the highest vegetable nitrate intake quintile (median, 141 mg/day) had 2.58 mmHg lower baseline systolic BP (95%CI − 3.12, − 2.05) and 1.38 mmHg lower diastolic BP (95%CI − 1.66, − 1.10), compared with participants in the lowest quintile. Vegetable nitrate intake was inversely associated with CVD plateauing at moderate intakes (~ 60 mg/day); this appeared to be mediated by systolic BP (21.9%). Compared to participants in the lowest intake quintile (median, 23 mg/day), a moderate vegetable nitrate intake (median, 59 mg/day) was associated with 15% lower risk of CVD [HR (95% CI) 0.85 (0.82, 0.89)]. Moderate vegetable nitrate intake was associated with 12%, 15%, 17% and 26% lower risk of ischemic heart disease, heart failure, ischemic stroke and peripheral artery disease hospitalizations respectively. Consumption of at least ~ 60 mg/day of vegetable nitrate (~ 1 cup of green leafy vegetables) may mitigate risk of CVD. Supplementary Information The online version contains supplementary material available at 10.1007/s10654-021-00747-3.

Non-alcoholic fatty liver disease (NAFLD) is considered the hepatic representation of the metabolic disorders. Inorganic nitrate/nitrite can be converted to nitric oxide, regulate glucose metabolism, lower lipid levels, and reduce inflammation, thus raising the hypothesis that inorganic nitrate/nitrite could be beneficial for improving NAFLD. This study assessed the therapeutic effects of chronic dietary nitrate on NAFLD in a mouse model. 60 ApoE−/- mice were fed a high-fat diet (HFD) for 12 weeks to allow for the development of atherosclerosis with associated NAFLD. The mice were then randomly assigned to different groups (20/group) for a further 12 weeks: (i) HFD + NaCl (1 mmol/kg/day), (ii) HFD + NaNO3 (1 mmol/kg/day), and (iii) HFD + NaNO3 (10 mmol/kg/day). A fourth group of ApoE−/- mice consumed a normal chow diet for the duration of the study. At the end of the treatment, caecum contents, serum, and liver were collected. Consumption of the HFD resulted in significantly greater lipid accumulation in the liver compared to mice on the normal chow diet. Mice whose HFD was supplemented with dietary nitrate for the second half of the study, showed an attenuation in hepatic lipid accumulation. This was also associated with an increase in hepatic AMPK activity compared to mice on the HFD. In addition, a significant difference in bile acid profile was detected between mice on the HFD and those receiving the high dose nitrate supplemented HFD. In conclusion, dietary nitrate attenuates the progression of liver steatosis in ApoE−/- mice fed a HFD.

A higher intake of food rich in flavonoids such as quercetin can reduce the risk of CVD. Enzymatically modified isoquercitrin (EMIQ®) has a bioavailability 17-fold higher than quercetin aglycone and has shown potential CVD moderating effects in animal studies. The present study aimed to determine whether acute ingestion of EMIQ® improves endothelial function, blood pressure (BP) and cognitive function in human volunteers at risk of CVD. Twenty-five participants (twelve males and thirteen females) with at least one CVD risk factor completed this randomised, controlled, crossover study. In a random order, participants were given EMIQ® (2 mg aglycone equivalent)/kg body weight or placebo alongside a standard breakfast meal. Endothelial function, assessed by flow-mediated dilatation (FMD) of the brachial artery was measured before and 1·5 h after intervention. BP, arterial stiffness, cognitive function, BP during cognitive stress and measures of quercetin metabolites, oxidative stress and markers of nitric oxide (NO) production were assessed post-intervention. After adjustment for pre-treatment measurements and treatment order, EMIQ® treatment resulted in a significantly higher FMD response compared with the placebo (1·80 (95 % CI 0·23, 3·37) %; P = 0·025). Plasma concentrations of quercetin metabolites were significantly higher (P < 0·001) after EMIQ® treatment compared with the placebo. No changes in BP, arterial stiffness, cognitive function or biochemical parameters were observed. In this human intervention study, the acute administration of EMIQ® significantly increased circulating quercetin metabolites and improved endothelial function. Further clinical trials are required to assess whether health benefits are associated with long-term EMIQ® consumption.

The cause of perioperative myocardial infarction (PMI) is postulated to involve hemodynamic stress or coronary plaque destabilization. We aimed to evaluate perioperative factors in patients with peripheral artery disease (PAD) undergoing major vascular surgery to determine the likely mechanisms and predictors of PMI.This was a prospective cohort study of 133 patients undergoing major vascular surgery including open abdominal aortic aneurysm (AAA) repair (n = 40) and major suprainguinal or infrainguinal arterial bypasses (non-AAA; n = 93). Preoperative assessment with history, physical examination, and peripheral artery tonometry was performed in addition to plasma sampling of biomarkers associated with inflammation and coronary plaque instability. The primary outcome was occurrence of a 30-day cardiovascular event (CVE; composite of PMI [troponin I elevation99th percentile reference of ≥0.1 μg/L], stroke, or death).Of 133 patients, 36 patients (27%) developed a 30-day CVE after vascular surgery, and all were PMI. Patients with 30-day CVE were older (75 ± 8 years vs 69 ± 10 years, mean ± standard deviation; P = .001), had higher prevalence of hypertension (94% vs 79%; P = .01) and preoperative beta-blocker therapy (50% vs 29%; P = .02), and had longer duration of surgery (5.1 ± 1.8 hours vs 4.0 ± 1.1 hours; P .0001). Significant elevations in cystatin C, N-terminal pro-B-type natriuretic peptide (NT-proBNP), troponin I, high-sensitivity troponin T, matrix metalloproteinase 3, and osteoprotegerin occurred in those who developed 30-day CVE (all P .05). Multivariate binary logistic regression identified AAA surgery and log-transformed NT-proBNP to be independent preoperative predictors of 30-day CVE (area under the receiver operating characteristic curve = 0.81).In patients with peripheral artery disease undergoing major vascular surgery, the likely mechanism of PMI appears to be the hemodynamic stress related to the type and duration of surgery. NT-proBNP was a useful independent predictor of CVE and thus may serve as an important biomarker of cardiovascular fitness for surgery.

Background Non-resolving inflammation associates with obesity and insulin resistance, and may be dependent on the balance of inflammatory substances and specialised pro-resolving mediators of inflammation (SPM) that act to halt the inflammatory response. This controlled trial examined the effect of weight loss on neutrophil synthesis of SPM in volunteers with the metabolic syndrome (MetS). Methods Volunteers with MetS (n = 42) were matched for age and gender and randomly assigned to a 12-wk weight loss program followed by 4-wk weight stabilization or a 16-wk weight maintenance program. At baseline and 16 weeks, isolated neutrophils were stimulated with calcium ionophore and the released SPM were measured by LC-MS/MS. Results At baseline the SPM resolvin (Rv) E1, 18R-RvE3, RvD2 and Maresin-1 (MaR-1) were detected from stimulated neutrophils. The concentration of released RvE1 was at least 6-fold that of other detected SPM. Weight loss of 4.7 ± 0.8 kg, led to a 2-fold increase in RvE1, P = 0.013, relative to the weight maintenance group. The increase in RvE1 after weight loss was related to, but independent of leukotriene B4. Conclusion Following weight loss, human neutrophils from individuals with the metabolic syndrome are capable of releasing larger amounts of RvE1 upon stimulation.

Insufficient nitric oxide (NO) bioavailability plays an important role in endothelial dysfunction, and increased NO has the potential to enhance cerebral blood flow (CBF). Dietary supplementation with sodium nitrate, a precursor of NO, could improve cerebrovascular function, but this has not been investigated. In 17 individuals, we examined the effects of a 7-day supplementation of dietary nitrate (0.1 mmol·kg−1·day −1) on cerebrovascular function using a randomized, single-blinded placebo-controlled crossover design. We hypothesized that 7-day dietary nitrate supplementation increases CBF response to CO2 (cerebrovascular CO2 reactivity) and cerebral autoregulation (CA). We assessed middle cerebral artery blood velocity (MCAv) and blood pressure (BP) at rest and during CO2 breathing. Transfer function analysis was performed on resting beat-to-beat MCAv and BP to determine CA, from which phase, gain, and coherence of the BP-MCAv data were derived. Dietary nitrate elevated plasma nitrate concentration by ~420% ( P < 0.001) and lowered gain ( d = 1.2, P = 0.025) and phase of the BP-MCAv signal compared with placebo treatment ( d = 0.7, P = 0.043), while coherence was unaffected ( P = 0.122). Dietary nitrate increased the MCAv-CO2 slope in a sex-specific manner (interaction: P = 0.016). Dietary nitrate increased the MCAv-CO2 slope in men ( d = 1.0, P = 0.014 vs. placebo), but had no effect in women ( P = 0.919). Our data demonstrate that dietary nitrate greatly increased cerebrovascular CO2 reactivity in healthy individuals, while its effect on CA remains unclear. The selective increase in the MCAv-CO2 slope observed in men indicates a clear sexual dimorphic role of NO in cerebrovascular function. NEW & NOTEWORTHY We found dietary nitrate supplementation improved the brain blood vessels’ response to CO2, cerebrovascular CO2 reactivity, without affecting blood pressure in a group of healthy individuals. Meanwhile, the effect of dietary nitrate on the relationship between blood pressure and brain blood flow, cerebral autoregulation, was inconclusive. The improvement in cerebrovascular CO2 reactivity was only observed in the male participants, alluding to a sex difference in the effect of dietary nitrate on brain blood flow control. Our findings indicate that dietary nitrate could be an effective strategy to enhance cerebrovascular CO2 reactivity.

A diet rich in polyphenolic compounds has recognized health benefits, and as such is routinely monitored as part of dietary intervention studies. A method for the simultaneous determination of 36 phenolic compounds, including phenolic acids and flavonoids, using liquid chromatography and tandem mass spectrometry is described here. The target analytes were quantified based on their specific mass spectral fragments using a selected reaction monitoring approach. A C18 column with embedded aromatic functionality ensured separation of all phenolic compounds studied which included several pairs of isomers. Sample preparation involved the use of β-glucuronidase to release the phenolic compounds from their conjugated forms. The intra-day and inter-day precision and accuracy was less than 7% for all phenolic compounds studied. Recoveries, where plasma was spiked with three different concentrations of the analytes, ranged from 95-115%. The limits of detection and quantification were 0.23-3.89 and 1.15-7.79 nM, respectively. The method was successfully applied to real samples and the range reported for each phenolic compound, with the exception of hydroferulic acid, nordihydroguaiaretic acid, methylgallate, and m-coumaric acid, was at least an order of magnitude higher than the limit of quantification for the method.

Flavonoids, plant-derived polyphenolic compounds, have been linked with health benefits. However, evidence from observational studies is incomplete; studies on cancer mortality are scarce and moderating effects of lifestyle risk factors for early mortality are unknown. In this prospective cohort study including 56,048 participants of the Danish Diet, Cancer, and Health cohort crosslinked with Danish nationwide registries and followed for 23 years, there are 14,083 deaths. A moderate habitual intake of flavonoids is inversely associated with all-cause, cardiovascular- and cancer-related mortality. This strong association plateaus at intakes of approximately 500 mg/day. Furthermore, the inverse associations between total flavonoid intake and mortality outcomes are stronger and more linear in smokers than in non-smokers, as well as in heavy (>20 g/d) vs. low-moderate (, The studies showing health benefits of flavonoids and their impact on cancer mortality are incomplete. Here, the authors perform a prospective cohort study in Danish participants and demonstrate an inverse association between regular flavonoid intake and both cardiovascular and cancer related mortality.

Oxidative stress has been identified as a process which is detrimental to brain health, and associated with age-related cognitive declines. Few studies to-date have examined the relationship between in vivo oxidative stress biomarkers and cognitive performance within healthy elderly populations. The current study investigated the relationship between reaction time and oxidative stress, as measured by blood plasma concentrations of F2-isoprostanes using a sample of 251 healthy, non-demented, elderly volunteers (Male; 111: Female 140) aged 60-75 years from the Australian Research Council Longevity Intervention (ARCLI) study cohort. A Jensen Box was used in conjunction with the Hick paradigm in order to differentiate simple from choice reaction time (two, four and eight-choice conditions) as well as movement (MT) and decision times (DT). MT, but not DT, was found to be significantly slower for participants in the high F2-isoprostane group compared to the low F2-isoprostane group, across all stimulus choices. F2-isoprostanes, age and Wechsler Abbreviated Scale of Intelligence (WASI) full scale intelligence quotient (IQ) were found to be significant predictors of average MT in the sample as a whole. These findings provide preliminary evidence to suggest that higher levels of oxidative stress may be associated with impaired psychomotor speed in the healthy elderly population.

Quercetin possesses various health beneficial functions, but its poor bioavailability limits these functions. Enzymatically modified isoquercitrin (EMIQ) is a quercetin glycoside with a greater bioavailability than quercetin. In this study, we investigated whether EMIQ regulates energy metabolism in mice and its underlying molecular mechanism. Male C57BL/6 mice were fed a normal diet with different doses of EMIQ or quercetin (0.02%, 0.1% and 0.5%) for two weeks. Supplementation with 0.1% EMIQ significantly decreased white adipose tissue (WAT) weight. Supplementation with 0.02% and 0.1% EMIQ promoted phosphorylation of adenosine monophosphate activated protein kinase (AMPK) in the WAT, liver, and muscle. In the WAT, 0.1% EMIQ downregulated peroxisome proliferator-activated receptor (PPAR)γ, CCAAT-enhancer-binding protein (C/EBP)α, C/EBPβ, and sterol regulatory element-binding protein 1 expression, as well as upregulated mitochondrial uncoupling protein (UCP) 2 and carnitine palmitoyltransferase-1 expression. Supplementation with 0.1% EMIQ also promoted the expression of thermogenesis-associated factors including PPARγ coactivator α (PGC-1α), UCP1, PR-domain containing protein 16, and sirtuin 1 in the WAT. In the liver, EMIQ promoted the phosphorylation of acetyl-CoA carboxylase, and increased the expression of PPARα, constitutive androstane-receptor, and farnesoid X receptor. Furthermore, supplementation with 0.02% or 0.1% EMIQ suppressed the plasma glucose level accompanied by the translocation of glucose transporter 4 to the plasma membrane of the muscle. Our results suggest that EMIQ is a potential food additive for the regulation of energy metabolism through AMPK phosphorylation.

OBJECTIVES: Our objective was to examine whether dietary intakes of vitamin K1 and vitamin K2 were associated with all-cause, cardiovascular disease (CVD)-related and cancer-related mortality and to identify subpopulations that may benefit the most from higher vitamin K intakes. METHODS: Participants from the Danish Diet, Cancer, and Health Study cohort, between 50–65 years of age at recruitment, completed a food-frequency questionnaire (FFQ) at baseline and were followed up for cancer-related, CVD-related, and all-cause mortality using nationwide registries. Intakes of vitamin K1 (phylloquinone) and vitamin K2 (menaquinones 4–10) were estimated from FFQs, and their relationship with mortality outcomes was determined using Cox proportional hazards models. RESULTS: In total, 56 048 Danish residents, with a median [interquartile range] age of 56 [52–60] years at entry, were followed up for 21 [20–22] years. During follow-up, 14 083 individuals died from any cause; 5015 deaths were CVD-related; and 6342 deaths were cancer-related. Intakes of vitamin K1, but not vitamin K2, were non-linearly inversely associated with both all-cause and cause-specific mortality, after adjusting for demographic and lifestyle confounders. Compared to individuals with the lowest vitamin K1 intakes, individuals with the highest intakes had a 24% [HR (95% CI): 0.76 (0.72, 0.79)] lower risk of all-cause mortality, a 28% [0.72 (0.66, 0.79)] lower risk of CVD-related mortality, and a 20% [0.80 (0.75, 0.86)] lower risk of cancer-related mortality. Furthermore, the association between vitamin K1 intake and cancer mortality appeared to be stronger in smokers than in non-smokers (p for interaction = 0.002). CONCLUSIONS: Moderate to high intakes of vitamin K1, but not K2, were associated with a lower risk of all-cause, CVD-related and cancer-related, mortality. Promoting adequate intakes of vitamin K1, particularly in smokers, may help to reduce all-cause, CVD-related and cancer-related mortality at the population level. FUNDING SOURCES: The Danish Diet, Cancer, and Health Study was funded by the Danish Cancer Society, Denmark. This study was supported by the Raine Medical Research Foundation and the Healy Medical Research Foundation.

Reported associations between vitamin K1 and both all-cause and cause-specific mortality are conflicting. The 56,048 participants from the Danish Diet, Cancer, and Health prospective cohort study, with a median [IQR] age of 56 [52–60] years at entry and of whom 47.6% male, were followed for 23 years, with 14,083 reported deaths. Of these, 5015 deaths were CVD-related, and 6342 deaths were cancer-related. Intake of vitamin K1 (phylloquinone) was estimated from a food-frequency questionnaire (FFQ), and its relationship with mortality outcomes was investigated using Cox proportional hazards models. A moderate to high (87–192 µg/d) intake of vitamin K1 was associated with a lower risk of all-cause [HR (95%CI) for quintile 5 vs quintile 1: 0.76 (0.72, 0.79)], cardiovascular disease (CVD)-related [quintile 5 vs quintile 1: 0.72 (0.66, 0.79)], and cancer-related mortality [quintile 5 vs quintile 1: 0.80 (0.75, 0.86)], after adjusting for demographic and lifestyle confounders. The association between vitamin K1 intake and cardiovascular disease-related mortality was present in all subpopulations (categorised according to sex, smoking status, diabetes status, and hypertension status), while the association with cancer-related mortality was only present in current/former smokers (p for interaction = 0.002). These findings suggest that promoting adequate intakes of foods rich in vitamin K1 may help to reduce all-cause, CVD-related, and cancer-related mortality at the population level. Supplementary Information The online version contains supplementary material available at 10.1007/s10654-021-00806-9.

Endothelial dysfunction, with impaired bioavailability and/or bioactivity of the vasoprotective molecule, nitric oxide, appears to be a vital step in the initiation of atherosclerosis. Several studies have shown that dietary nitrate/nitrite can have significant benefits on human cardiovascular homeostasis. Although serum nitrite concentrations can reach micromolar levels, the physiological significance of nitrate/nitrite in normal tissues has not been fully elucidated. We investigated in vitro the chronic effects of nitrate/nitrite on endothelial nitric oxide synthase (eNOS) to determine the potential vasoprotective effects of nitrate/nitrite and the underlying molecular mechanisms. Our results demonstrate the expression of phosphorylated eNOS at Ser1177 and phosphorylated adenosine monophosphate activated protein kinase (AMPK) at Thr172 in human aortic endothelial cells were increased after nitrite treatment. We suggest that nitrite stimulation may enhance eNOS activation, which is due, in part, to AMPK activation. The AMPK–eNOS activation by nitrite may be a possible molecular mechanism underlying the vascular protective effects of dietary nitrate.

Objectives: Cardiovascular and neurocognitive responses to chewing gum have been reported, but the mechanisms are not well understood. Chewing gum after a nitrate-rich meal may upregulate the reduction of oral nitrate to nitrite and increase nitric oxide (NO), a molecule important to cardiovascular and neurocognitive health. We aimed to explore effects of chewing gum after a nitrate-rich meal on nitrate metabolism (through the enterosalivary nitrate-nitrite-NO pathway), endothelial function, blood pressure (BP), neurocognitive performance, mood and anxiety.\ud \ud Methods: Twenty healthy men (n=6) and women (n=14) with a mean age of 48 years (range: 23-69) were recruited to a randomized controlled cross-over trial. After consumption of a nitrate-rich meal (180 mg of nitrate), we assessed the acute effects of chewing gum, compared to no gum chewing, on (i) salivary nitrate, nitrite and the nitrate reductase ratio (100 x [nitrite] / ([nitrate] + [nitrite]); (ii) plasma nitrite, S-nitrosothiols and other nitroso species (RXNO); (iii) endothelial function (measured by flow mediated dilatation); (iv) BP; (v) neurocognitive performance; (vi) mood; and (vii) anxiety.\ud \ud Results: Consumption of the nitrate-rich meal resulted in a significant increase in markers of nitrate metabolism. A significantly higher peak flow mediated dilatation was observed with chewing compared to no chewing (baseline adjusted mean difference: 1.10%, 95% CI: 0.06, 2.14; p=0.038) after the nitrate-rich meal. A significant small increase in systolic BP, diastolic BP and heart rate were observed with chewing compared to no chewing after the nitrate-rich meal. The study did not observe increased oral reduction of nitrate to nitrite and NO, or improvements in neurocognitive performance, mood or anxiety with chewing compared to no chewing.\ud \ud Conclusion: Chewing gum after a nitrate-rich meal resulted in an acute improvement in endothelial function and a small increase in BP but did not result in acute effects on neurocognitive function, mood or anxiety.

Background: The role of nutrition in the primary prevention of peripheral artery disease (PAD), the third leading cause of atherosclerotic cardiovascular disease, is undetermined. Flavonoids may attenuate atherosclerosis and therefore persons who consume flavonoid-rich foods may have a lower risk of developing PAD.Objectives: We aimed to examine the association between flavonoid intake and PAD hospitalizations and investigate if the association differs according to established risk factors for PAD.Methods: Baseline data from 55,647 participants of the Danish Diet, Cancer, and Health Study without PAD, recruited from 1993 to 1997, were cross-linked with Danish nationwide registries. Flavonoid intake was calculated from FFQs using the PhenolExplorer database. Associations were examined using multivariableadjusted restricted cubic splines based on Cox proportional hazards models.Results: After a median [IQR] follow-up time of 21 [20-22] y, 2131 participants had been hospitalized for any PAD. The association between total flavonoid intake and total PAD hospitalizations was nonlinear, reaching a plateau at similar to 750-1000 mg/d. Compared with the median flavonoid intake in quintile 1 (174 mg/d), an intake of 1000 mg/d was associated with a 32% lower risk of any PAD hospitalization (HR: 0.68; 95% CI: 0.60, 0.77), a 26% lower risk of atherosclerosis (HR: 0.74; 95% CI: 0.62, 0.88), a 28% lower risk of an aneurysm (HR: 0.72; 95% CI: 0.59, 0.88), and a 47% lower risk of a hospitalization for other peripheral vascular disease (HR: 0.53; 95% CI: 0.42, 0.67). A higher total flavonoid intake was also significantly associated with a lower incidence of revascularization or endovascular surgery and lower extremity amputation. The association between total flavonoid intake and PAD hospitalizations differed according to baseline smoking status, alcohol intake, BMI, and diabetes status.Conclusions: Ensuring the adequate consumption of flavonoid-rich foods, particularly in subpopulations prone to the development of atherosclerosis, may be a key strategy to lower the risk of PAD.

Background Dietary vitamin K (K 1 and K 2 ) may reduce atherosclerotic cardiovascular disease (ASCVD) risk via several mechanisms. However, studies linking vitamin K intake with incident ASCVD are limited. We aimed to determine the relationship between dietary vitamin K intake and ASCVD hospitalizations. Methods and Results In this prospective cohort study, participants from the Danish Diet, Cancer, and Health Study, with no prior ASCVD, completed a food‐frequency questionnaire at baseline and were followed up for hospital admissions of ASCVD; ischemic heart disease, ischemic stroke, or peripheral artery disease. Intakes of vitamin K 1 and vitamin K 2 were estimated from the food‐frequency questionnaire, and their relationship with ASCVD hospitalizations was determined using Cox proportional hazards models. Among 53 372 Danish citizens with a median (interquartile range) age of 56 (52–60) years, 8726 individuals were hospitalized for any ASCVD during 21 (17–22) years of follow‐up. Compared with participants with the lowest vitamin K 1 intakes, participants with the highest intakes had a 21% lower risk of an ASCVD‐related hospitalization (hazard ratio, 0.79; 95% CI: 0.74–0.84), after multivariable adjustments for relevant demographic covariates. Likewise for vitamin K 2 , the risk of an ASCVD‐related hospitalization for participants with the highest intakes was 14% lower than participants with the lowest vitamin K 2 intake (hazard ratio, 0.86; 95% CI, 0.81–0.91). Conclusions Risk of ASCVD was inversely associated with diets high in vitamin K 1 or K 2 . The similar inverse associations with both vitamin K 1 and K 2 , despite very different dietary sources, highlight the potential importance of vitamin K for ASCVD prevention.

Introduction: Prospective studies investigating flavonoid intake and dementia risk are scarce. The aims of this study were to examine associations between flavonoid intake and the risk of incident dementia and to investigate whether this association differs in the presence of lifestyle risk factors for dementia.Methods: We examined associations in 55,985 participants of the Danish Diet, Cancer, and Health Study followed for 23 years. The Phenol-Explorer database was used to estimate flavonoid intakes. Information on incident dementia and dementia subtypes was obtained using Danish patient and prescription registries. Hazard ratios (HRs) were calculated using restricted cubic splines in multivariable-adjusted Cox proportional hazards models.Results: For incident dementia, moderate compared to low intakes of flavonols (HR: 0.90 [0.82, 0.99]), flavanol oligo+polymers (HR: 0.87 [0.79, 0.96]), anthocyanins (HR: 0.84 [0.76, 0.93]), flavanones (HR: 0.89 [0.80, 0.99]), and flavones (HR: 0.85 [0.77, 0.95]) were associated with a lower risk. For vascular dementia, moderate intakes of flavonols (HR: 0.69 [0.53, 0.89]) and flavanol oligo + polymers (HR: 0.65 [0.51, 0.83]) were associated with lower risk. Flavonoid intakes were not significantly associated with Alzheimer's disease or unspecified dementia. The inverse association between total flavonoid intake and incident dementia was stronger in "ever" smokers than in "never" smokers and in those without hypercholesterolemia versus those with hypercholesteremia. Furthermore, the inverse association of vascular dementia with a moderate total flavonoid intake was stronger in "ever" smokers and those who were "normal" to "overweight" versus "never" smokers or those who were "obese," respectively.Conclusion: A moderate intake of flavonoid-rich foods may help to reduce dementia risk.

Reported associations between vitamin K1 and both all-cause and cause-specific mortality are conflicting. The 56,048 participants from the Danish Diet, Cancer, and Health prospective cohort study, with a median [IQR] age of 56 [52–60] years at entry and of whom 47.6% male, were followed for 23 years, with 14,083 reported deaths. Of these, 5015 deaths were CVD-related, and 6342 deaths were cancer-related. Intake of vitamin K1 (phylloquinone) was estimated from a food-frequency questionnaire (FFQ), and its relationship with mortality outcomes was investigated using Cox proportional hazards models. A moderate to high (87–192 µg/d) intake of vitamin K1 was associated with a lower risk of all-cause [HR (95%CI) for quintile 5 vs quintile 1: 0.76 (0.72, 0.79)], cardiovascular disease (CVD)-related [quintile 5 vs quintile 1: 0.72 (0.66, 0.79)], and cancer-related mortality [quintile 5 vs quintile 1: 0.80 (0.75, 0.86)], after adjusting for demographic and lifestyle confounders. The association between vitamin K1 intake and cardiovascular disease-related mortality was present in all subpopulations (categorised according to sex, smoking status, diabetes status, and hypertension status), while the association with cancer-related mortality was only present in current/former smokers (p for interaction = 0.002). These findings suggest that promoting adequate intakes of foods rich in vitamin K1 may help to reduce all-cause, CVD-related, and cancer-related mortality at the population level.

Background & Aims: Primary prevention of atrial fibrillation (AF) through behavioural and dietary modification is a critically important and unmet need. Flavonoids are bioactive dietary compounds with promising cardiovascular health benefits. Our aim was to investigate the association between flavonoid intake and clinically apparent AF. Methods: Baseline data from 55 613 participants of the Danish Diet, Cancer and Health Study, without AF, recruited between 1993 and 1997, were cross-linked with Danish nationwide registries. Total flavonoid and flavonoid subclass intakes were calculated from validated food frequency questionnaires using the Phenol-Explorer database. Associations between flavonoid intake and incident AF (first-time hospitalization or outpatient visit) were examined using restricted cubic splines based on Cox proportional hazards models. Results: During a median [IQR] follow-up of 21 [18 – 22] years, 7291 participants were diagnosed with AF. Total flavonoid intake was not statistically significantly associated with risk of incident AF in the whole cohort. However, compared to the lowest quintile, a total flavonoid intake of 1000 mg/day was associated with a lower risk of AF in smokers [0.86 (0.77, 0.96)] but not in non-smokers [0.96 (0.88, 1.06)], and a lower risk of AF in high alcohol consumers [>20 g/d: 0.84 (0.75, 0.95)] but not in low-to-moderate alcohol consumers [

Introduction: Apples, an important contributor to total dietary phenolic intake, are associated with cardiovascular health benefits. Determining the phenolic composition of apples, their individual variation across varieties, and the phenolic compounds present in plasma after apple consumption is integral to understanding the effects of apple phenolics on cardiovascular health. Methods: Using liquid chromatography we quantified five important polyphenols and one phenolic acid with potential health benefits: quercetin glycosides, (−)-epicatechin, procyanidin B2, phloridzin, anthocyanins, and chlorogenic acid, in the skin and flesh of 19 apple varieties and 72 breeding selections from the Australian National Apple Breeding program. Furthermore, we measured the phenolic compounds in the plasma of 30 individuals post-consumption of an identified phenolic-rich apple, Cripp's Pink. Results: Considerable variation in concentration of phenolic compounds was found between genotypes: quercetin (mean ± SD: 16.1 ± 5.9, range: 5.8–30.1 mg per 100 g); (−)-epicatechin (mean ± SD: 8.6 ± 5.8, range: 0.2–19.8 mg per 100 g); procyanidin B2 (mean ± SD: 11.5 ± 6.6, range: 0.5–26.5 mg per 100 g); phloridzin (mean ± SD: 1.1 ± 0.6, range: 0.3–4.3 mg per 100 g); anthocyanins (mean ± SD: 1.8 ± 4.4, range: 0–40.8 mg per 100 g); and chlorogenic acid (mean ± SD: 11.3 ± 9.9, range: 0.4–56.0 mg per 100 g). All phenolic compounds except chlorogenic acid were more concentrated in the skin compared with flesh. We observed a significant increase, with wide variation, in 14 phenolic compounds in plasma post-consumption of a phenolic-rich apple. Conclusion: This information makes an important contribution to understanding the potential health benefits of apples.

There is an accumulating body of literature reporting on dietary flavonoid intake and the risk of cardiovascular disease (CVD) in prospective cohort studies. This makes apparent the need for an overview and update on the current state of the science. To date, at least 27 prospective cohorts (in 44 publications) have evaluated the association between estimated habitual flavonoid intake and CVD risk. At this time, the totality of evidence suggests long-term consumption of flavonoid-rich foods may be associated with a lower risk of fatal and non-fatal ischemic heart disease (IHD), cerebrovascular disease, and total CVD; disease outcomes which are principally, though not exclusively, composed of cases of atherosclerotic CVD (ASCVD). To date, few studies have investigated outcome specific ASCVD, such as peripheral artery disease (PAD) or ischemic stroke. Of the flavonoid subclasses investigated, evidence more often implicates diets rich in anthocyanins, flavan-3-ols, and flavonols in lowering the risk of CVD. Although inferences are restricted by confounding and other inherent limitations of observational studies, causality appears possible based on biological plausibility, temporality, and the relative consistency of the reported associations. However, whether the associations observed represent a benefit of the isolated bioactives per se, or are a signal of the bioactives acting in concert with the co-occurring nutrient matrix within flavonoid-bearing foods, are issues of consideration. Thus, the simple interpretation, and the one most relevant for dietary advice, is that consumption of flavonoid-rich foods or diets higher in flavonoids, appear nutritionally beneficial in the prevention of CVD.

Background High vegetable intake is associated with beneficial effects on bone. However, the mechanisms remain uncertain. Green leafy vegetables are a rich source of vitamin K1, which is known to have large effects on osteoblasts and osteocalcin (OC) metabolism. Objective To examine the effects of consumption of two to three extra serves of green leafy vegetables daily on bone metabolism. Methods Thirty individuals (mean age 61.8 ± 9.9 years, 67% male) completed three experimental phases in a randomised controlled crossover design, each lasting four weeks, with a washout period of four weeks between phases (clinical trial registration: ACTRN12615000194561). The three experimental phases were: (i) increased dietary vitamin K1 by consuming green leafy vegetables (H-K; ~200 g/d containing 164.3 [99.5–384.7] μg/d of vitamin K1); (ii) low vitamin K1 by consuming vitamin K1-poor vegetables (L-K; ~200 g/d containing 9.4 [7.7–11.6] μg/d of vitamin K1); and (iii) control (CON) where participants consumed an energy-matched non-vegetable control. OC forms, total OC (tOC), carboxylated OC (cOC) and undercarboxylated OC (ucOC), were measured in serum pre- and post-intervention for each experimental phase using a sandwich-electrochemiluminescence immunoassay. Results Pre-intervention tOC, ucOC and ucOC:tOC levels were similar between phases (P > .05). Following H-K, but not L-K, tOC, ucOC and ucOC:tOC levels were significantly lower compared to pre-intervention levels (P ≤ .001) and compared to CON (~14%, 31% and 19%, respectively, all P, Highlights • Habitual dietary vitamin K1 from green leafy vegetables reduces serum tOC and ucOC. • Vitamin K recommendations

Cardiovascular disease is the leading cause of death and disability worldwide. Recent work suggests a link between vitamin K insufficiency and deficiency with vascular calcification, a marker of advanced atherosclerosis. Vitamin K refers to a group of fat-soluble vitamins important for blood coagulation, reducing inflammation, regulating blood calcium metabolism, as well as bone metabolism, all of which may play a role in promoting cardiovascular health. Presently, there is a lack of a comprehensive vitamin K database on individual foods, which are required to accurately calculate vitamin K1 and K2 intake for examination in epidemiological studies. This has likely contributed to ambiguity regarding the recommended daily intake of vitamin K, including whether vitamin K1 and K2 may have separate, partly overlapping functions. This review will discuss the presence of: (i) vitamin K1 and K2 in the diet; (ii) the methods of quantitating vitamin K compounds in foods; and (iii) provide an overview of the evidence for the cardiovascular health benefits of vitamin K in observational and clinical trials.

Short-term trials indicate inorganic nitrate and nitrate-rich vegetables may have vascular health benefits. However, few observational studies have explored the relationship between nitrate intake and long-term cardiovascular disease (CVD) outcomes. The primary aim of this study was to investigate the association of nitrate intake from vegetables with CVD mortality in a sample of older Australians. A subgroup of participants without diabetes or major CVD at baseline (1992–1994) were included from the Blue Mountains Eye Study, a population-based cohort study of men and women aged ≥ 49 years. Diets were evaluated using a validated food frequency questionnaire at baseline, 5 years and 10 years of follow-up. Vegetable nitrate intake was estimated using a comprehensive vegetable nitrate database. Cox proportional hazard regression was used to explore the association between vegetable nitrate intake and CVD mortality. During 14 years of follow-up, 188/2229 (8.4%) participants died from CVD. In multivariable-adjusted analysis, participants in quartile 2 [69.5–99.6 mg/day; HR 0.53 (95% CI 0.35, 0.82)], quartile 3 [99.7–137.8 mg/day; HR 0.51 (95% CI 0.32, 0.80)], and quartile 4 [> 137.8 mg/day; HR 0.63 (95% CI 0.41, 0.95)] of vegetable nitrate intake had lower hazards for CVD mortality compared to participants in quartile 1 (

Dietary fibre positively influences gut microbiome composition, enhancing the metabolism of dietary flavonoids to produce bioactive metabolites. These synergistic activities facilitate the beneficial effects of dietary flavonoids on cardiometabolic health parameters. The aims of this study were to investigate whether isoquercetin (a major dietary flavonoid) and inulin (soluble fibre), either alone or in combination could improve features of the metabolic syndrome. Following a 1 week acclimatization, male C57BL6 mice (6–8 weeks) were randomly assigned to; (i) normal chow diet (n = 10), (ii) high fat (HF) diet (n = 10), (iii) HF diet + 0.05% isoquercetin (n = 10), (iv) HF diet + 5% inulin, or (v) HF diet + 0.05% isoquercetin + 5% inulin (n = 10). Body weight and food intake were measured weekly. At 12 weeks, glucose and insulin tolerance tests were performed, and blood, faecal samples, liver, skeletal muscle and adipose tissue were collected. At 12 weeks, mice on the HF diet had significantly elevated body weights as well as impaired glucose tolerance and insulin sensitivity compared to the normal chow mice. Supplementation with either isoquercetin or inulin had no effect, however mice receiving the combination had attenuated weight gain, improved glucose tolerance and insulin sensitivity, reduced hepatic lipid accumulation, adipocyte hypertrophy, circulating leptin and adipose FGF21 levels, compared to mice receiving the HF diet. Additionally, mice on the combination diet had improvements in the composition and functionality of their gut microbiome as well as production of short chain fatty acids. In conclusion, long-term supplementation with the dietary flavonoid isoquercetin and the soluble fibre inulin can attenuate development of the metabolic syndrome in mice fed a high fat diet. This protective effect appears to be mediated, in part, through beneficial changes to the microbiome.

Background Emerging evidence suggests that increasing intakes of nitrate-rich vegetables may be an effective approach to reduce blood pressure. Objective Our primary aim was to determine whether daily consumption of nitrate-rich vegetables over 4 wk would result in lower blood pressure. Design Thirty participants with prehypertension or untreated grade 1 hypertension were recruited to a randomized controlled crossover trial with 4-wk treatment periods separated by 4-wk washout periods. Participants completed 3 treatments in random order: 1) increased intake (∼200 g/d) of nitrate-rich vegetables [high-nitrate (HN); ∼150 mg nitrate/d], 2) increased intake (∼200 g/d) of nitrate-poor vegetables [low-nitrate (LN); ∼22 mg nitrate/d], and 3) no increase in vegetables (control; ∼6 mg nitrate/d). Compliance was assessed with the use of food diaries and by measuring plasma nitrate and carotenoids. Nitrate metabolism was assessed with the use of plasma, salivary, and urinary nitrate and nitrite concentrations. The primary outcome was blood pressure assessed by using 24-h ambulatory, home, and clinic measurements. Secondary outcomes included measures of arterial stiffness. Results Plasma nitrate and nitrite concentrations increased with the HN treatment in comparison to the LN and control treatments (P 0.05) after adjustment for pretreatment values, treatment period, and treatment order. Similarly, no differences were observed between treatments for arterial stiffness measures (P > 0.05). Conclusion Increased intake of nitrate-rich vegetables did not lower blood pressure in prehypertensive or untreated grade 1 hypertensive individuals when compared with increased intake of nitrate-poor vegetables and no increase in vegetables. This trial was registered at www.anzctr.org.au as ACTRN12615000194561.

Age-associated cognitive decline amongst otherwise healthy older individuals is a multifaceted characteristic of ageing. The role of oxidative stress biomarkers has been increasingly examined in the context of pathological aging conditions that affect cognition. Plasma F2-Isoprostane levels are a reliable index of systemic oxidative stress (specifically lipid peroxidation) and are elevated in dementia patients. Less is known about their role in healthy cognitive ageing. This study evaluated the relationship between F2-Isoprostanes and cognitive functioning in a cohort of 211 healthy elderly adults (60–75 years: Male; 88, Female; 123). Cognitive assessment included the Cognitive Drug Research (CDR) computerised assessment battery, which produces five validated factor scores (corresponding to ‘Quality of Episodic Memory’, ‘Speed of Memory’, Quality of Working Memory’, Power of Attention’ and ‘Continuity of Attention’). Participants with higher F2-Isoprostane levels had significantly lower Quality of Episodic Memory scores (suggesting inferior abilities in retaining and retrieving verbal information in episodic memory). This is, to our knowledge, the first report of compromised verbal episodic memory in healthy ageing humans being linked to increased levels of F2-Isoprostanes. These results have relevance for interventions aimed at improving cognitive performance in the healthy elderly.