Habitual intake of flavonoid subclasses and incident hypertension in adults

Associations between flavonoid-rich food and flavonoid intakes and incident unhealthy aging outcomes in older United States males and females

BACKGROUND

Our knowledge of the importance of flavonoid-rich foods in preventing unhealthy aging across its different domains is limited.

OBJECTIVES

This study aimed to examine prospective associations between flavonoid-rich food and flavonoid intakes and indicators of unhealthy aging, namely frailty, impaired physical function, and poor mental health.

METHODS

We followed up 62,743 females and 23,687 males, all aged ≥60 y, from the Nurses' Health Study (1990-2014) and Health Professionals Follow-up Study (2006-2018), respectively. Both time-updated and change in intakes of a flavodiet score (an aggregate of intakes of major flavonoid-rich foods and beverages) and individual flavonoid-rich foods and beverages and time-updated intakes of total flavonoids and flavonoid subclasses were calculated from food frequency questionnaires collected at baseline and every subsequent 4 y. Associations with incident frailty, impaired physical function, and poor mental health, assessed from self-reported questionnaire responses, were examined with multivariable-adjusted Cox proportional hazards models.

RESULTS

In the Nurses' Health Study, participants with the highest flavodiet scores, compared with the lowest, had a 15% lower risk of frailty (HRQ5vsQ1: 0.85; 95%CI: 0.80, 0.90), a 12% lower risk of impaired physical function (HRQ5vsQ1: 0.88; 95% CI: 0.84, 0.91), and a 12% lower risk of poor mental health (HRQ5vsQ1: 0.88; 95% CI: 0.82, 0.94). Increases in flavodiet scores and both higher intakes and increases in intakes of tea, red wine, apples, blueberries, and oranges tended to be associated with lower risks of all outcomes. Higher intakes of total flavonoids and all flavonoid subclasses tended to be associated with a lower risk of each outcome. Although fewer associations were observed among males in the Health Professionals Follow-up Study, those with the highest flavodiet scores had a lower risk of poor mental health.

CONCLUSIONS

High intakes of flavonoid-rich foods may support healthy aging. Further research is needed, including examining sex-specific associations, as incorporating flavonoid-rich foods in the diet may be a simple strategy to support healthy aging.

Dietary Factors and Cognitive Function: with a Focus on Subjective Cognitive Decline

PURPOSE OF THE REVIEW

Age-related cognitive decline is an important global challenge. Substantial evidence suggests that diet may prevent or delay cognitive aging. This narrative review examines recent literature on how dietary factors influence cognitive function, with a focus on subjective cognitive decline (SCD).

RECENT FINDINGS

Higher intakes of flavonoids, carotenoids, and plant-based protein were associated with lower odds of SCD. Berries, citrus fruits and juices, carotenoid-rich and green leafy vegetables, and beans/legumes were among the foods with the strongest inverse associations with SCD. Healthy dietary patterns, such as the Mediterranean and MIND diet, may be beneficial for maintaining subjective cognitive function. Healthy choice of diet may play a role in lowering the risk of late-life SCD.

A Review of the Effects of Flavonoids on NAD(P)H Quinone Oxidoreductase 1 Expression and Activity

Cancer is a significant cause of death worldwide. It has been suggested that the consumption of flavonoids decreases the risk for cancer by increasing phase II enzymes, such as Nicotinamide Adenine Dinucleotide Phosphate Hydrogen (NAD(P)H) quinone oxidoreductase 1 (NQO1), glutathione S-transferases, and Uridine 5'-diphospho- (UDP)-glucuronosyltransferases that assist in removing carcinogens from the human body. Flavonoids are bioactive compounds found in a variety of dietary sources, including fruits, vegetables, legumes, nuts, and teas. As such, it is important to investigate which flavonoids are involved in the metabolism of carcinogens to help reduce the risk of cancer. Therefore, the objective of this narrative review was to investigate the effects of commonly consumed flavonoids on NQO1 mRNA expression, protein, and activity in human cell and murine models. PubMed was used to search for peer-reviewed journal articles, which demonstrated that selected flavonoids (e.g., quercetin, apigenin, luteolin, genistein, and daidzein) increase NQO1, and therefore, increase the excretion of carcinogens. However, more research is needed regarding the mechanisms by which flavonoids induce NQO1. Furthermore, it is suggested that future efforts focus on providing precise flavonoid recommendations to decrease the risk factors for chronic diseases.

The Role of Inflammatory Markers in Linking Metabolic Syndrome to Cognitive Decline in Middle-Aged Women: A Focus on TNF-α and IL-6

Background: Metabolic syndrome (MetS) and related disorders, such as insulin resistance, pose significant health risks in middle-aged women, including cognitive decline. Chronic inflammation, characterized by elevated levels of interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-α), has been identified as a key mechanism linking metabolic disturbances to neurodegenerative processes. Methods: This study aimed to examine the associations between metabolic disorders, inflammatory markers, and cognitive function among middle-aged women. A cross-sectional study was conducted on 179 non-smoking perimenopausal and postmenopausal women aged 43-73 years. Anthropometric, metabolic, and cognitive parameters were assessed, including body mass index (BMI), waist-to-height ratio (WHtR), fasting glucose (GLU), triglycerides (TG), IL-6, TNF-α, and Mini-Mental State Examination (MMSE) scores. Logistic regression models were applied to evaluate the relationships between inflammation, MetS components, and cognitive impairments. Results: Women with insulin resistance showed significantly worse metabolic profiles and lower MMSE scores (23.98 vs. 24.91, p = 0.032). IL-6 levels were strongly associated with hypertriglyceridemia (OR = 1.096, 95% CI: 1.044-1.151, p < 0.001) and insulin resistance (OR = 1.068, 95% CI: 1.030-1.107, p < 0.001), while TNF-α correlated with abdominal obesity (WHtR OR = 1.429, 95% CI: 1.005-2.031, p = 0.047). Moreover, TNF-α was a significant predictor of cognitive impairments (OR = 1.362, 95% CI: 1.153-1.610, p < 0.001), whereas IL-6 showed no significant association. Conclusions: These findings highlight that TNF-α may be a key inflammatory marker associated with metabolic disturbances and cognitive decline in middle-aged women. IL-6 appears to be more specifically linked to lipid abnormalities and insulin resistance. Targeted interventions to reduce inflammation may moderate metabolic and cognitive risks in this population.

Phytochemicals, Organic Acid, and Vitamins in Red Rhapsody Strawberry-Content and Storage Stability

Strawberries are highly perishable fruits harvested at full ripeness, and their nutritional quality together with their phytochemical composition can be significantly affected by storage duration and temperature. This study investigated the changes in key bioactive compounds, including folate, vitamin C, anthocyanins, quercetin-3-glucoside, ellagic acid, and organic acids, in "Red Rhapsody" strawberries stored at two typical household temperatures (4 °C and 23 °C). While storage duration and temperature did not have a significant impact (p > 0.05) on folate content, significant changes in other phytochemicals were observed. The total anthocyanin content increased significantly (p < 0.05), from 30.0 mg/100 g fresh weight (FW) at Day 0 to 84.4 mg/100 g FW at Day 7 at 23 °C, a 2.8-fold increase. Conversely, the vitamin C content was significantly reduced (p < 0.05), from 54.1 mg/100 g FW at Day 0 to 28.4 mg/100 g FW at Day 7 at 23 °C, while it remained stable at 4 °C. Additionally, the concentrations of quercetin-3-glucoside, ellagic acid, and organic acids underwent significant changes during the storage period. The total folate content fluctuated between 73.2 and 81.6 μg/100 g FW at both temperatures. These results suggest that storage temperature and duration influence the individual phytochemicals and nutrients of strawberries differently, with potential implications for their nutritional value and bioactive compound content.

Effects of Vaccinium-derived antioxidants on human health: the past, present and future

Dietary intake of Vaccinium berries has demonstrated significant potential in preventing many risk factors associated with metabolic syndromes in the human population. In recent years, a multitude of research has shown the role of antioxidants derived from Vaccinium berries on chronic diseases such as cardiovascular disorders, diabetes, obesity, and cancer. Several studies have also investigated the effect of Vaccinium berry consumption on their ability to modulate the risk factors associated with oxidative stress, vascular function, inflammation, and lipid metabolism. Regarding cancer, studies showed that the consumption of berries reduces inflammation, inhibits angiogenesis, protects against DNA damage within the cell, and controls apoptosis and proliferation rates in malignant tumours. However, which components are responsible for the health benefits is still unclear. Reports show that whole berry consumption usually confers positive effects on human health, and the health-promoting potentials are likely due to the presence of polyphenols with antioxidant activities. Among these polyphenols, various Vaccinium berry species have been reported to contain anthocyanins and flavonoids. These two polyphenolic compounds are known to have higher antioxidant activity and are beneficial for human health. There are now several studies and human clinical trials documenting the beneficial effects of Vaccinium berries, and these findings suggest that they may be promising for preventing and treating neurodegenerative diseases. This review focuses primarily on dietary Vaccinium berries consumption effects on human health and their potential role as therapeutic agents.

Potential of Anthocyanin-rich Products to Prevent and Improve Endothelial Function and Senescence: Focus on Anthocyanins

Endothelial dysfunction is a pivotal early event in the development of major cardiovascular diseases including hypertension, atherosclerosis, diabetes, and aging. The alteration of the endothelial function is often triggered by an imbalance between the endothelial formation of vasoprotective factors, including nitric oxide (NO) and endothelium-dependent hyperpolarization (EDH), and vasocontracting factors, such as arachidonic acid-derived mediators generated by cyclooxygenases, and an increased level of oxidative stress. Recently, endothelial senescence was reported to be an early trigger of endothelial dysfunction. Preclinical studies indicate that polyphenol-rich food, including anthocyanin-rich products, can activate pathways promoting an increased formation of vasoprotective factors and can prevent the induction of endothelial dysfunction in endothelial cells and isolated blood vessels. Similarly, intake of anthocyanin-rich products has been associated with the prevention and/or the improvement of an endothelial dysfunction in several experimental models of cardiovascular diseases, including physiological aging. Moreover, clinical data indicate that polyphenol-rich and anthocyanin-rich products can improve endothelial function and vascular health in humans with cardiovascular diseases. The present review will discuss both experimental and clinical evidence indicating that several polyphenol-rich foods and natural products, and especially anthocyanin-rich products, can promote endothelial and vascular health, as well as the underlying mechanisms.

Optimization of Ultrasound Extraction of Total Anthocyanin From Berberis kaschgarica Rupr. by Response Surface Methodology and Its Antihypertensive Effect

Berberis kaschgarica Rupr. is a berry fruit shrub found in the north-western region of China, locally its fruit is consumed as a tea ingredient a part of the daily diet, for treatment of different diseases like eczema, and for cardiovascular care as a traditional remedy. In the current study, an optimized ultrasound-assisted extraction (UAE) method is developed using response surface methodology (RSM) to extract anthocyanins from the fruit. The influence of the extraction conditions on the yield of anthocyanins was evaluated and discussed. Additionally, the antihypertensive activity of the extract was evaluated in rats. The negative control group comprised Wistar-Kyoto rats, while five experimental groups included spontaneously hypertensive rats: model group; captopril group; and three treatment groups receiving purified extract. Blood pressure was regularly monitored every 2 weeks during the 12-week treatment period. Post-treatment left ventricular cardiac function in rats was assessed, and serum level of renin (REN), angiotensin-converting enzyme (ACE), angiotensin II (Ang-II), angiotensin-(1-7) (Ang-(1-7)), endothelin-1 (ET-1) and nitric oxide (NO) were evaluated. The optimal UAE extraction condition determined by RSM was 56.5% ethanol volume, 1:19.74 solid-to-liquid ratio, 55 min extraction time, and 0.71% of HCL volume. The purified B. kaschgarica anthocyanin extract exhibited antihypertensive effects and significantly improved left ventricular cardiac functions in treated rats. Furthermore, serum levels of REN, ACE, Ang-II, ET-1, Ang-(1-7), and NO showed statistically significant changes in the treated groups. This study highlights the efficacy of the developed optimized UAE method for high-yield anthocyanin extraction from B. kaschgarica fruit and its potential as a therapeutic agent for hypertension.

Pre- and post-polyphenol intake and ovarian cancer survival: evidence from a prospective cohort study

PURPOSE

Although (poly)phenols have shown potential in anti-cancer activities, their impact on improving ovarian cancer (OC) survival remains unknown. Therefore, we aim to first investigate the association between dietary polyphenol intake and OC survival, providing valuable insights into potential interventions.

METHODS

The prospective cohort recruited 560 patients with OC to assess the associations of polyphenol intake, not only pre- and post-diagnosis but also the change from pre- to post-diagnosis with OC survival. Dietary intakes of total (poly)phenols and their five classes (flavonoids, phenolic acids, lignans, stilbenes, and other polyphenols) were assessed using a validated 111-item food frequency questionnaire. Overall survival (OS) was tracked through active follow-up and medical records until February 16th, 2023. Cox proportional hazard regression models were applied to calculate the hazard ratios (HR) and 95% confidence intervals (CI).

RESULTS

During a median follow-up of 44.4 months, 211 all-cause deaths were identified. We observed significant associations between higher polyphenol intake with lower risk of mortality among patients with OC ((HR T3 vs. T1 = 0.55, 95%CI = 0.35-0.87 for pre-diagnosis; and HR T3 vs. T1 = 0.59, 95%CI = 0.39-0.90 for post-diagnosis). Consistently, an evident linear trend was observed for polyphenol and flavonoid intake with OC survival. Of note, compared to the stable group (change within 10%), the decreased intake (change of more than 10%) of total (poly)phenols and five polyphenol classes was significantly associated with worse OS.

CONCLUSION

Dietary (poly)phenols, as well as its five classes, have an inverse association with OC survival.

The association between dietary polyphenol intake and the odds of metabolic syndrome

Oxidative stress plays a role in the pathophysiology of metabolic syndrome (MetS), and one of the most important features of polyphenols is their antioxidant properties. However, there is no universal consensus on the effectiveness of polyphenols in treating Mets. Therefore, the present study aimed to investigate the association between polyphenols and MetS in an Iranian sample. This cross-sectional study was conducted on an adult population sample from Shiraz, in southern Iran. MetS was calculated using the criteria of the Adult Treatment Panel III (ATP III), which defines MetS as the presence of three or more of the specified risk factors. A validated food frequency questionnaire (FFQ) was used to measure the participant's food intake. The association between polyphenol intake and the odds on MetS and its components was assessed using logistic regression. In both univariate and multivariate models, the association between polyphenol intake and the risk of MetS was not significant. However, after adjusting for potential confounders in the multivariate model, each unit change in flavonol, flavanone and isoflavones intake was associated with a lower, higher, and higher odds of MetS, respectively (flavonols: odds ratio (OR) = 0.926, 95% confidence interval (CI) 0.891-0.963, P < 0.001-flavanones: OR = 1.007, 95% CI: 1.001-1.014, P = 0.034-isoflavones: OR = 4.920, 95% CI: 1.057-22.894, P = 0.042). Additionally, no significant association was found between polyphenol intake and the risk of MetS components. However, in the multivariate model, after adjusting for potential confounders, a significant association was observed between polyphenol intake and lower odds of high waist circumference (OR = 0.998, 95% CI: 0.996-0.999, P = 0.032). The present study did not reveal a significant association between overall polyphenol intake and the odds of MetS. However, certain subclasses of polyphenols appear to be associated with the likelihood of MetS and its components.

Strawberry (Fragaria x Ananassa) intake on human health and disease outcomes: a comprehensive literature review

Strawberries provide a number of potential health promoting phytonutrients to include phenolics, polyphenols, fiber, micronutrients and vitamins. The objective of this review is to provide a comprehensive summary of recent human studies pertaining to the intake of strawberry and strawberry phytonutrients on human health. A literature search conducted through PubMed and Cochrane databases consolidated studies focusing on the effects of strawberry intake on human health. Articles were reviewed considering pre-determined inclusion and exclusion criteria, including experimental or observational studies that focused on health outcomes, and utilized whole strawberries or freeze-dried strawberry powder (FDSP), published between 2000-2023. Of the 60 articles included in this review, 47 were clinical trials, while 13 were observational studies. A majority of these studies reported on the influence of strawberry intake on cardiometabolic outcomes. Study designs included those examining the influence of strawberry intake during the postprandial period, short-term trials randomized with a control, or a single arm intake period controlling with a low polyphenolic diet or no strawberry intake. A smaller proportion of studies included in this review examined the influence of strawberry intake on additional outcomes of aging including bone and brain health, and cancer risk. Data support that the inclusion of strawberries into the diet can have positive impacts during the postprandial period, with daily intake improving outcomes of lipid metabolism and inflammation in those at increased cardiovascular risk.

Protective effects of flavonoids against intracerebral and subarachnoid hemorrhage (Review)

Intracerebral hemorrhage (ICH), known as non-traumatic cerebrovascular rupture and hemorrhage, often occurs in the deep basal brain segment. It is known for its high morbidity and mortality rates. Subarachnoid hemorrhage (SAH) is a clinical syndrome caused by the rupture of blood vessels at the base or surface of the brain that allows blood to flow directly into the subarachnoid space. It progresses quickly and typically manifests at younger ages compared with ICH. ICH and SAH are both devastating events in the category of hemorrhagic strokes and are attracting increasing attention from researchers. Flavonoids, being important natural molecules, have remarkable anti-inflammatory and antioxidant effects. Flavonoids have extensive biological activities in inflammation and oxidative stress (OS), and have protective effects in vascular function associated with cerebrovascular diseases. They have an impact on the onset of ICH and SAH by targeting various pathways, including the suppression of inflammation and OS. Recently, the role of flavonoid compounds in ICH and SAH has also received increasing interest. Thus, to serve as a resource for the prevention and treatment of ICH and SAH, the present review provided an overview of the research on flavonoid compounds in the prevention of brain damage after these two conditions have occurred.

Microbial synthesis of anthocyanins and pyranoanthocyanins: current bottlenecks and potential solutions

Anthocyanins (ACNs) are secondary metabolites found in plants. Due to their impressive biological activities, ACNs have gained significant popularity and extensive application within the food, pharmaceutical, and nutraceutical industries. A derivative of ACNs: pyranoanthocyanins (PACNs) possesses more stable properties and interesting biological activities. However, conventional methods for the production of ACNs, including chemical synthesis and plant extraction, involve organic solvents. Microbial synthesis of ACNs from renewable biomass, such as amino acids or flavonoids, is considered a sustainable and environmentally friendly method for large-scale production of ACNs. Recently, the construction of microbial cell factories (MCFs) for the efficient biosynthesis of ACNs and PACNs has attracted much attention. In this review, we summarize the cases of microbial synthesis of ACNs, and analyze the bottlenecks in reconstructing the metabolic pathways for synthesizing PACNs in microorganisms. Consequently, there is an urgent need to investigate the mechanisms behind the development of MCFs for PACNs synthesis. Such research also holds significant promise for advancing the production of food pigments. Meanwhile, we propose potential solutions to the bottleneck problem based on metabolic engineering and enzyme engineering. Finally, the development prospects of natural food and biotechnology are discussed.

Nailfold Capillaroscopy: A Comprehensive Review on Its Usefulness in Both Clinical Diagnosis and Improving Unhealthy Dietary Lifestyles

Since the 1970s, the utility of nailfold capillaroscopy (NFC) in diagnosing rheumatological disorders such as systemic sclerosis has been well established. Further studies have also shown that NFC can detect non-rheumatic diseases such as diabetes, glaucoma, dermatitis, and Alzheimer disease. In the past decade, nailfold capillary morphological changes have also been reported as symptoms of unhealthy lifestyle habits such as poor diet, smoking, sleep deprivation, and even psychological stress, all of which contribute to slow blood flow. Therefore, studying the relationships between the morphology of nailfold capillaries and lifestyle habits has a high potential to indicate unhealthy states or even pre-disease conditions. Simple, inexpensive, and non-invasive methods such as NFC are important and useful for routine medical examinations. The present study began with a systematic literature search of the PubMed database followed by a summary of studies reporting the assessment of morphological changes detected by NFC, and a comprehensive review of NFC's utility in clinical diagnosis and improving unhealthy dietary lifestyles. It culminates in a summary of dietary and lifestyle health promotion strategy, assessed based on NFC and other related measurements that indicate healthy microvascular blood flow and endothelial function.

The state of the science on the health benefits of blueberries: a perspective

Mounting evidence indicates that blueberry consumption is associated with a variety of health benefits. It has been suggested that regular consumption of blueberries can support and/or protect against cardiovascular disease and function, pre-diabetes and type 2 diabetes, and brain and cognitive function in individuals with health conditions and age-related decline. Further, mechanistic investigations highlight the role of blueberry anthocyanins in mediating these health benefits, in part through interactions with gut microbiota. Also, nutritional interventions with blueberries have demonstrated the ability to improve recovery following exercise-induced muscle damage, attributable to anti-inflammatory effects. Despite these advancements in blueberry health research, research gaps persist which affects the generalizability of findings from clinical trials. To evaluate the current state of knowledge and research gaps, a blueberry health roundtable with scientific experts convened in Washington, DC (December 6-7, 2022). Discussions centered around five research domains: cardiovascular health, pre-diabetes and diabetes, brain health and cognitive function, gut health, and exercise recovery. This article synthesizes the outcomes of a blueberry research roundtable discussion among researchers in these domains, offering insights into the health benefits of blueberries and delineating research gaps and future research directions.

Associations of Flavonoid Intakes with Mortality among Populations with Hypertension: A Prospective Cohort Study

BACKGROUND

The effect of flavonoid consumption on all-cause and special-cause mortality remains unclear among populations with hypertension.

METHODS

A total of 6110 people with hypertension from three NHANES survey cycles (2007-2008, 2009-2010, and 2017-2018) were enrolled in this study. Cox proportional hazard models were conducted to estimate the association between the intake of total flavonoids and flavonoid subclasses and all-cause, cancer-related, and cardiovascular disease (CVD)-related mortality. Nonlinear relationships were identified using restricted cubic splines (RCS).

RESULTS

During 43,977 person-years of follow-up, 1155 participants died from any cause, 282 participants died from CVD, and 265 participants died from cancer. After adjusting for relevant confounders, including demographic, lifestyle, and dietary intake, a higher intake of total flavonoids was significantly associated with lower all-cause mortality but not CVD-related and cancer-related mortality among the population with hypertension. Compared with extreme quartiles, the hazard ratio (HR) and 95% confidence interval (CI) were 0.74 (0.56-0.97) for all-cause mortality, 0.77 (0.40-1.46) for CVD-related mortality, and 0.62 (0.35-1.08) for cancer-related mortality. In terms of all-cause mortality, this inverse association was optimized at total flavonoid consumption of approximately 375 mg/day. In addition, the negative association between total flavonoid consumption and all-cause mortality was more pronounced in non-obese (BMI < 30 kg/m2) compared to obese (BMI ≥ 30 kg/m2) populations. Higher intakes of anthocyanidin, flavan-3-ol, flavonol, and isoflavone were significantly associated with lower all-cause mortality (HR (95%CI): 0.70 (0.55-0.89); 0.76 (0.59-0.96); 0.66 (0.46-0.94); 0.79 (0.67-0.93), respectively). Higher intakes of anthocyanidin, flavan-3-ol, and flavonol were significantly associated with lower cancer-related mortality (HR (95%CI): 0.55 (0.32-0.93); 0.51 (0.31-0.82); 0.52 (0.28-0.96), respectively).

CONCLUSION

This study suggests that a heightened consumption of total flavonoids and some flavonoid subclasses was linked to lower mortality, which supports the proposal of increasing flavonoid intake as part of healthy diets in patients with hypertension.

Therapeutic potential of berries in age-related neurological disorders

Aging significantly impacts several age-related neurological problems, such as stroke, brain tumors, oxidative stress, neurodegenerative diseases (Alzheimer's, Parkinson's, and dementia), neuroinflammation, and neurotoxicity. Current treatments for these conditions often come with side effects like hallucinations, dyskinesia, nausea, diarrhea, and gastrointestinal distress. Given the widespread availability and cultural acceptance of natural remedies, research is exploring the potential effectiveness of plants in common medicines. The ancient medical system used many botanical drugs and medicinal plants to treat a wide range of diseases, including age-related neurological problems. According to current clinical investigations, berries improve motor and cognitive functions and protect against age-related neurodegenerative diseases. Additionally, berries may influence signaling pathways critical to neurotransmission, cell survival, inflammation regulation, and neuroplasticity. The abundance of phytochemicals in berries is believed to contribute to these potentially neuroprotective effects. This review aimed to explore the potential benefits of berries as a source of natural neuroprotective agents for age-related neurological disorders.

The association between flavonoids intake and hypertension in U.S. adults: A cross-sectional study from The National Health and Nutrition Examination Survey

Although in vitro experiments have demonstrated the potential of flavonoid compounds in regulating blood pressure, there is still a lack of evidence from large population studies. We conducted a cross-sectional study using the National Health and Nutrition Examination Survey to investigate the relationship between flavonoid intake levels (natural log transformation) and hypertension events. A total of 15 752 participants aged over 20 years were included, and a weighted multivariable logistic regression analysis was performed to explore the relationship between total flavonoids, five sub types intake, and hypertension events. Smooth curve fitting was used to explore potential nonlinear relationships. Higher total flavonoids intake was associated with a lower risk of hypertension than the lowest group. The adjusted odds ratios (95% CIs) were 0.79 (0.70-0.88) for total flavonoids intake. Elevated total flavonoids intake levels were significantly and linearly associated with a lower risk of hypertension. For each unit increase in the total flavonoids intake level, the adjusted ORs for risk of hypertension decrease by 5% (OR 0.95; 95% CI, 0.92-0.98). In addition, in restricted cubic spline regression, we found that flavan-3-ols, anthocyanidins, and flavonols intake were linearly and negatively related to prevalence of hypertension. Flavones intake showed nonlinear associations with prevalence of hypertension with inflection points of -1.90. Within a certain range, a negative correlation exists between flavonoids intake and hypertension events. This finding provides insights into dietary modifications in the prevention of hypertension.

Association between dietary flavonoid intake and hypertension among U.S. adults

Background

Hypertension is one of the major risk factors for cardiovascular disease. Dietary flavonoids have been reported to reduce inflammation, protect against oxidative stress, protect the vascular endothelium, and improve vascular health. However, the relationship between dietary flavonoid intake and the prevalence of hypertension remains controversial.

Methods

This study included 8010 adults from the 2007-2010 and 2017-2018 National Health and Nutrition Examination Surveys (NHANES). The relationship between dietary flavonoid intake and the prevalence of hypertension was explored by weighted logistic regression and weighted restricted cubic spline.

Results

We found an inverse relationship between total anthocyanin intake and the prevalence of hypertension in the fourth quartile compared with the first quartile [0.81(0.66,0.99), p = 0.04]. Moreover, the prevalence of hypertension tended to decrease with increasing total anthocyanin intake in participants over 60 years of age. In addition, we found a U-shaped relationship between the prevalence of hypertension and total flavan-3-ol intake. Total flavan-3-ol intake was inversely associated with hypertension prevalence in the third quartile compared with the first quartile [0.79 (0.63,0.99), p = 0.04]. Moreover, there was a significant negative association between the prevalence of hypertension and total flavan-3-ol intake when total flavan-3-ol intake was below 48.26 mg/day.

Conclusion

Our study found a negative association between the prevalence of hypertension and moderate total anthocyanins intake and total flavan-3-ols intake. Our study provides evidence from a population-based study for a negative association between dietary flavonoid intake and the prevalence of hypertension.

Association between dietary flavonol intake and mortality risk in the U.S. adults from NHANES database

Using updated National Health and Nutrition Examination Survey (NHANES) follow-up data, and a large nationwide representative sample of adult U.S. citizens, the aim of this study was to explore the relationship between dietary flavonol intake, all-cause and cause-specific mortality risks. In this prospective cohort study based on NHANES (2007-2008, 2009-2010, and 2017-2018), a total of 11,679 participants aged 20 years and above were evaluated. The amount and type of food taken during a 24-h dietary recall were used to estimate dietary flavonol intake, which includes total flavonol, isorhamnetin, kaempferol, myricetin, and quercetin. Each analysis of the weighted data was dealt with in accordance with the NHANES reporting requirements' intricate stratification design. The Cox proportional risk regression model or Fine and Gray competing risks regression model were applied to evaluate all-cause and cause-specific mortality risks, respectively. The follow-up period was calculated using the time interval between the baseline and the death date or December 31, 2019 (whichever occurs first). Each data analysis was performed between October 1, 2023, and October 22, 2023. Dietary flavonol intake included total flavonol, isorhamnetin, kaempferol, myricetin, and quercetin. Up to December 31, 2019, National Death Index (NDI) mortality data were used to calculate mortality from all causes as well as cause-specific causes. A total of 11,679 individuals, which represents 44,189,487 U.S. non-hospitalized citizens, were included in the study; of these participants, 49.78% were male (n = 5816), 50.22% were female (n = 5, 863); 47.56% were Non-Hispanic White (n = 5554), 18.91% were Non-Hispanic Black (n = 2209), 16.23% were Mexican American (n = 1895), and 17.30% were other ethnicity (n = 2021); The mean [SE] age of the sample was 46.93 [0.36] years, with a median follow-up of 7.80 years (interquartile range, 7.55-8.07 years). After adjusting covariates, Cox proportional hazards models and fine and gray competing risks regression models for specific-cause mortality demonstrated that total flavonol intake was associated with all-cause (HR 0.64, 95% CI 0.54-0.75), cancer-specific (HR 0.45, 95% CI 0.28-0.70) and CVD-specific (HR 0.67, 95% CI 0.47-0.96) mortality risks; isorhamnetin intake was associated with all-cause (HR 0.72, 95% CI 0.60-0.86), and cancer-specific (HR 0.62, 95% CI 0.46-0.83) mortality risks; kaempferol intake was associated with all-cause (HR 0.74, 95% CI 0.63-0.86), and cancer-specific (HR 0.62, 95% CI 0.40-0.97) mortality risks; myricetin intake was associated with all-cause (HR 0.77, 95% CI 0.67-0.88), AD-specific (HR 0.34, 95% CI 0.14-0.85), and CVD-specific (HR 0.61, 95% CI 0.47-0.80) mortality risks; quercetin intake was associated with all-cause (HR 0.66, 95% CI 0.54-0.81), cancer-specific (HR 0.54, 95% CI 0.35-0.84), and CVD-specific (HR 0.61, 95% CI 0.40-0.93) mortality risks; there was no correlation observed between dietary flavonol intake and DM-specific mortality. According to the current study, all-cause, AD, cancer, and CVD mortality risks declined with increased dietary flavonoid intake in the U.S. adults. This finding may be related to the anti-tumor, anti-inflammatory, and anti-oxidative stress properties of flavonol.

Protective effects of blueberries on vascular function: A narrative review of preclinical and clinical evidence

Blueberries are rich in nutrients and (poly)phenols, popular with consumers, and a major agricultural crop with year-round availability supporting their use in food-based strategies to promote human health. Accumulating evidence indicates blueberry consumption has protective effects on cardiovascular health including vascular dysfunction (i.e., endothelial dysfunction and arterial stiffening). This narrative review synthesizes evidence on blueberries and vascular function and provides insight into underlying mechanisms with a focus on oxidative stress, inflammation, and gut microbiota. Evidence from animal studies supports beneficial impacts on vascular function. Human studies indicate acute and chronic blueberry consumption can improve endothelial function in healthy and at-risk populations and may modulate arterial stiffness, but that evidence is less certain. Results from cell, animal, and human studies suggest blueberry consumption improves vascular function through improving nitric oxide bioavailability, oxidative stress, and inflammation. Limited data in animals suggest the gut microbiome mediates beneficial effects of blueberries on vascular function; however, there is a paucity of studies evaluating the gut microbiome in humans. Translational evidence indicates anthocyanin metabolites mediate effects of blueberries on endothelial function, though this does not exclude potential synergistic and/or additive effects of other blueberry components. Further research is needed to establish the clinical efficacy of blueberries to improve vascular function in diverse human populations in a manner that provides mechanistic information. Translation of clinical research to the community/public should consider feasibility, social determinants of health, culture, community needs, assets, and desires, barriers, and drivers to consumption, among other factors to establish real-world impacts of blueberry consumption.

Development of a novel (poly)phenol-rich diet score and its association with urinary (poly)phenol metabolites

Background: Estimating (poly)phenol intake is challenging due to inadequate dietary assessment tools and limited food content data. Currently, a priori diet scores to characterise (poly)phenol-rich diets are lacking. This study aimed to develop a novel (poly)phenol-rich diet score (PPS) and explore its relationship with circulating (poly)phenol metabolites. Methods: A total of 543 healthy free-living participants aged 18-80 years completed a food frequency questionnaire (FFQ) (EPIC-Norfolk) and provided 24 h urine samples. The PPS was developed based on the relative intake (quintiles) of 20 selected (poly)phenol-rich food items abundant in the UK diet, including tea, coffee, red wine, whole grains, chocolate and cocoa products, berries, apples and juice, pears, grapes, plums, citrus fruits and juice, potatoes and carrots, onions, peppers, garlic, green vegetables, pulses, soy and soy products, nuts, and olive oil. Foods included in the PPS were chosen based on their (poly)phenol content, main sources of (poly)phenols, and consumption frequencies in the UK population. Associations between the PPS and urinary phenolic metabolites were investigated using linear models adjusting energy intake and multiple testing (FDR adjusted p < 0.05). Result: The total PPS ranged from 25 to 88, with a mean score of 54. A total of 51 individual urinary metabolites were significantly associated with the PPS, including 39 phenolic acids, 5 flavonoids, 3 lignans, 2 resveratrol and 2 other (poly)phenol metabolites. The total (poly)phenol intake derived from FFQs also showed a positive association with PPS (stdBeta 0.32, 95% CI (0.24, 0.40), p < 0.01). Significant positive associations were observed in 24 of 27 classes and subclasses of estimated (poly)phenol intake and PPS, with stdBeta values ranging from 0.12 (0.04, 0.20) for theaflavins/thearubigins to 0.43 (0.34, 0.51) for flavonols (p < 0.01). Conclusion: High adherence to the PPS diet is associated with (poly)phenol intake and urinary biomarkers, indicating the utility of the PPS to characterise diets rich in (poly)phenols at a population level.

The Effect of Hokkaido Red Wines on Vascular Outcomes in Healthy Adult Men: A Pilot Study

Moderate red wine intake has been associated with lower cardiovascular mortality, due in part to the intake of polyphenols and anthocyanins, whose content can vary from varietal and year of harvest. This study assessed the vascular effects in response to a single intake of 2015 and 2018 Zweigelt red wines from Hokkaido, Japan. Healthy men were randomly assigned to consume 240 mL each of a red wine, or a sparkling white grape juice as a control in a randomized three-arm cross-over design with a 7 day washout between arms. The augmentation index (AI; a measure of arterial stiffness) and AI at 75 beats/min (AI75), reactive hyperemia index, systolic and diastolic blood pressure (SBP and DBP, respectively), and platelet reactivity were assessed at baseline and two and four hours after each beverage intake. Changes from the baseline were analyzed using a linear mixed model. Significant treatment effects (p = 0.02) were observed, with AI 13% lower after the intake of the 2015 or 2018 vintages compared to the control. Intake of the 2018 vintage reduced SBP and DBP (-4.1 mmHg and -5.6 mmHg, respectively; p = 0.02) compared to the 2015 wine and the control drink. The amount of hydroxytyrosol in the 2018 wine was almost twice the amount as in the 2015 wine, which may help explain the variable blood pressure results. Future studies exploring the vascular effects of the same red wine from different vintage years and different phenolic profiles are warranted.

Dietary flavonoids intake contributes to delay biological aging process: analysis from NHANES dataset

BACKGROUND

Diet may influence biological aging and the discrepancy (∆age) between a subject's biological age (BA) and chronological age (CA). We aimed to investigate the correlation of dietary flavonoids with the ∆age of organs (heart, kidney, liver) and the whole body.

METHOD

A total of 3193 United States adults were extracted from the National Health and Nutrition Examination Survey (NHANES) in 2007-2008 and 2017-2018. Dietary flavonoids intake was assessed using 24-h dietary recall method. Multiple linear regression analysis was performed to evaluate the association of dietary flavonoids intake with the ∆age of organs (heart, kidney, liver) and the whole body. BA was computed based on circulating biomarkers, and the resulting ∆age was tested as an outcome in linear regression analysis.

RESULTS

The ∆age of the whole body, heart, and liver was inversely associated with higher flavonoids intake (the whole body ∆age β = - 0.58, cardiovascular ∆age β = - 0.96, liver ∆age β = - 3.19) after adjustment for variables. However, higher flavonoids intake positively related to renal ∆age (β = 0.40) in participants with chronic kidney disease (CKD). Associations were influenced by population characteristics, such as age, health behavior, or chronic diseases. Anthocyanidins, isoflavones and flavones had the strongest inverse associations between the whole body ∆age and cardiovascular ∆age among all the flavonoids subclasses.

CONCLUSION

Flavonoids intake positively contributes to delaying the biological aging process, especially in the heart, and liver organ, which may be beneficial for reducing the long-term risk of cardiovascular or liver disease.

Higher intake of dietary flavonols, specifically dietary quercetin, is associated with lower odds of frailty onset over 12 years of follow-up among adults in the Framingham Heart Study

BACKGROUND

Polyphenolic antioxidants derived from plant foods may reduce oxidative stress and frailty, but the effect of the polyphenol subclass of dietary flavonoids and their subclasses on frailty is uncertain.

OBJECTIVES

To determine the association between dietary flavonoids, their subclasses, quercetin (a specific flavonol), and frailty onset in adults.

METHODS

This prospective cohort study included individuals from the Framingham Heart Study with no frailty at baseline. Intake of total flavonoids, subclasses of flavonoids (flavonols, flavan-3-ols, flavonones, flavones, anthocyanins, and polymeric flavonoids), and quercetin were estimated via semi-quantitative FFQ along with frailty (Fried phenotype), and covariates at baseline (1998-2001). Frailty was re-evaluated in 2011-2014. Logistic regression estimated OR and 95% CIs for each flavonoid variable and frailty onset.

RESULTS

Mean age was 58.4 y (SD ± 8.3, n = 1701; 55.5% women). The mean total flavonoid intake was 309 mg/d (SD ± 266). After 12.4 (SD ± 0.8) y, 224 (13.2%) individuals developed frailty. Although total flavonoid intake was not statistically associated with frailty onset (adjusted OR: 1.00; 95% CI: 0.99-1.01), each 10 mg/d of higher flavonol intake was linked with 20% lower odds of frailty onset (OR: 0.80; 95% CI: 0.67-0.96). Other subclasses showed no association (P values range: 0.12-0.99), but every 10 mg/d of higher quercetin intake was associated with 35% lower odds of frailty onset (OR: 0.65; 95% CI: 0.48-0.88).

CONCLUSIONS

Although no association was observed between total flavonoid intake and frailty onset in adults, a higher intake of flavonols was associated with lower odds of frailty onset, with a particularly strong association for quercetin. This hypothesis-generating study highlights the importance of assessing specific subclasses of flavonoids and the potential of dietary flavonols and quercetin as a strategy to prevent the development of frailty.

Dietary Polyphenol Intake and Risk of Hypertension: An 18-y Nationwide Cohort Study in China

BACKGROUND

Although increasing evidence suggests that polyphenol helps regulate blood pressure (BP), evidence from large-scale and long-term population-based studies is still lacking.

OBJECTIVES

This study aimed to investigate the association between dietary polyphenol and hypertension risk in the China Health and Nutrition Survey (N = 11,056).

METHODS

Food intake was assessed using 3-d, 24-h dietary recalls and household weighing method; polyphenol intake was calculated by multiplying consumption of each food and its polyphenol content. Hypertension was defined as BP ≥ 140/90 mmHg, physicians' diagnosis, or taking antihypertension medications. HR and 95% CI were estimated using mixed-effects Cox models.

RESULTS

During 91,561 person-years of follow-up, a total of 3866 participants developed hypertension (35%). The lowest multivariable-adjusted HR (95% CI) of hypertension risk occurred in the third quartile intake, which was 0.63 (0.57, 0.70) for total polyphenol, 0.61 (0.55, 0.68) for flavonoid, 0.62 (0.56, 0.69) for phenolic acid, 0.46 (0.42, 0.51) for lignan, and 0.58 (0.52, 0.64) for stilbene, compared with the lowest quartile. The polyphenol-hypertension associations were nonlinear (all Pnonlinearity < 0.001), and different patterns were observed. U-shaped relations with hypertension were observed for total polyphenol, flavonoid, and phenolic acid, whereas L-shaped associations were observed for lignan and stilbene. Moreover, higher fiber intake strengthened the polyphenol-hypertension association, especially for lignan (P-interaction = 0.002) and stilbene (P-interaction = 0.004). Polyphenol-containing food, particularly vegetables and fruits rich in lignan and stilbene, were significantly associated with lower hypertension risk.

CONCLUSIONS

This study demonstrated an inverse and nonlinear association between dietary polyphenol, especially lignan and stilbene, and hypertension risk. The findings provide implications for hypertension prevention.

Effect of Dietary Berry Supplementation on Antioxidant Biomarkers in Adults with Cardiometabolic Risks: A Systematic Review of Clinical Trials

Cardiometabolic conditions are closely associated with inflammation and oxidative stress. Dietary berries may serve as a beneficial nutrition intervention to address the features of cardiometabolic dysfunction and associated oxidative stress. The high antioxidant status of dietary berries may increase antioxidant capacity and reduce biomarkers of oxidative stress. This systematic review was conducted to investigate these effects of dietary berries. The search was conducted using PubMed, Cochrane Library, Web of Science, and citation searching. Through this search we identified 6309 articles and 54 were included in the review. Each study's risk of bias was assessed using the 2019 Cochrane Methods' Risk of Bias 2 tool. Antioxidant and oxidative stress outcomes were evaluated, and the magnitude of effect was calculated using Cohen's d. A range of effectiveness was reported in the included studies and the quality of the studies differed between the parallel and crossover trials. Considering the inconsistency in reported effectiveness, future investigations are warranted to determine the acute and sustained reductions of oxidative stress biomarkers from dietary berry intake (PROSPERO registration# CRD42022374654).

Polyphenols and Triterpenes Combination in an In Vitro Model of Cardiac Damage: Protective Effects

Olive products contain high levels of monounsaturated fatty acids as well as other minor components such as triterpenic alcohols and other pentacyclic triterpenes, which together form the main triterpenes of virgin olive oil. Olive fruits and leaves contain significant amounts of hydrophilic and lipophilic bioactives including flavones, phenolic acids and phenolic alcohols, amongst others. Several studies have shown the benefits of these substances on the cardiovascular system. Regardless, little is known about the specific combination of bioactive compounds in cardiovascular health. Thus, we aimed to test the combination of a triterpenes (TT70) and a polyphenols (HT60) olive oil bioactive extract in H9c2 cells under stress conditions: LPS and H2O2 stimulation. To evaluate the effectiveness of the combination, we measured cell viability, superoxide production and protein expression of caspase 3, eNOS, peNOS, TNF-α and Il-6. Overall, cells stimulated with LPS or H2O2 and co-incubated with the combination of triterpenes and polyphenols had increased cell survival, lower levels of superoxide anion, lower protein expression of eNOS and higher expression of peNOS, increased protein expression of SOD-1 and lower protein expression of TNF-α and Il-6. The specific combination of HT60+TT70 is of great interest for further study as a possible treatment for cardiovascular damage.

Prospective Associations between Cumulative Average Intake of Flavonoids and Hypertension Risk in the CArdioVascular Disease Association Study (CAVAS)

In this study, we aimed to investigate the prospective associations and their shapes between the dietary intake of total flavonoids and their seven subclasses and hypertension risk in a prospective cohort, the KoGES_CArdioVascular disease Association Study (CAVAS), and to consider obesity status as an additional factor. A total of 10,325 adults aged 40 years and older were enrolled at baseline, and 2159 patients were newly diagnosed with hypertension during a median follow-up of 4.95 years. Cumulative dietary intake was estimated using a repeated food frequency questionnaire. Incidence rate ratios (IRRs) with 95% confidence intervals (CIs) were estimated using modified Poisson models with a robust error estimator. We observed nonlinear inverse associations between total and seven subclasses of flavonoids and hypertension risk, although there was no significant association between total flavonoids and flavones with hypertension risk in the highest quartile. For men, these inverse associations tended to be pronounced in the high BMI group, particularly for anthocyanins and proanthocyanidins [IRR (95% CI) in overweight/obese men: 0.53 (0.42-0.67) for anthocyanins; 0.55 (0.42-0.71) for proanthocyanidins]. Our results suggested that consumption of dietary flavonoids may not be dose-responsive but is inversely associated with hypertension risk, particularly among overweight/obese men.

Evidence of Flavonoids on Disease Prevention

A growing body of evidence highlights the properties of flavonoids in natural foods for disease prevention. Due to their antioxidative, anti-inflammatory, and anti-carcinogenic activities, flavonoids have been revealed to benefit skeletal muscle, liver, pancreas, adipocytes, and neural cells. In this review, we introduced the basic classification, natural sources, and biochemical properties of flavonoids, then summarize the experimental results and underlying molecular mechanisms concerning the effects of flavonoid consumption on obesity, cancers, and neurogenerative diseases that greatly threaten public health. Especially, the dosage and duration of flavonoids intervening in these diseases are discussed, which might guide healthy dietary habits for people of different physical status.

Secondary Metabolites From Plants for Cardiovascular Disease

One of the leading causes of mortality worldwide is cardiac vascular disease. According to the WHO report, CVDs affect 17.9 million people each year and will affect 22.2 million people by 2030. The plants include flavonoids, polyphenols, plant Sulphur compounds, and terpenoids, which are all active phytochemicals. Recent research has revealed that flavonoids are substances with strong biological effects that may help prevent chronic illnesses including cardiovascular disease. The prevention of low-density lipoprotein oxidation, which encourages vasodilatation, is a common flavonoid mode of action. Due to the rising frequency of CVD, numerous plants have been identified to contain a number of physiologically active chemicals with known biological effects; however, proper CVD preventive and treatment approaches are still needed. This study aims to emphasize the cardiovascular risk factors, in addition to explaining the processes through which naturally occurring bioactive chemicals exhibit their cardiovascular preventive effects.

The Relationship between Dietary Flavonols Intake and Metabolic Syndrome in Polish Adults

Metabolic syndrome (MetS) is a cluster of metabolic disorders primarily caused by central obesity, which results in chronic inflammation leading to hypertension, diabetes and atherogenic dyslipidemia. Inflammation underlying MetS could be the target for dietary flavonols as they present antioxidative properties. The aim of this paper was to analyze the differences in habitual intake of selected flavonols (quercetin, kaempferol, isorhamnetin and myricetin) between MetS patients and healthy participants, and its relationship with MetS advancement. Ninety participants were enrolled in this study. The one-year flavonol intake was assessed with a dedicated food frequency questionnaire. The patients with MetS consumed significantly less quercetin (p = 0.01), kaempferol (p = 0.04), isorhamnetin (p < 0.001), total flavonols (p = 0.01), tomatoes (p = 0.001) and wine (p = 0.01) daily. Further analysis revealed a moderate inverse correlation between quercetin (p = 0.001), kaempferol (p = 0.01), isorhamnetin (p < 0.001), total flavonols (p = 0.001) and tomato consumption (p = 0.004) and MetS stage. The analysis of laboratory parameters showed that dietary intake of flavonols was not correlated with lipid profile, glucose level or renal function. On the basis of this observation, a potential protective effect of dietary flavonols, mainly from tomatoes, against MetS could be suggested. However, when referring to MetS components, flavonols probably mainly impact central obesity and blood pressure, without a significant impact on conventional lipid-profile parameters and glucose level.

Effects of Fermented Food Consumption on Non-Communicable Diseases

The gastrointestinal flora consists of several microbial strains in variable combinations in both healthy and sick humans. To prevent the risk of the onset of disease and perform normal metabolic and physiological functions with improved immunity, a balance between the host and gastrointestinal flora must be maintained. Disruption of the gut microbiota triggered by various factors causes several health problems, which promote the progression of diseases. Probiotics and fermented foods act as carriers of live environmental microbes and play a vital role in maintaining good health. These foods have a positive effect on the consumer by promoting gastrointestinal flora. Recent research suggests that the intestinal microbiome is important in reducing the risk of the onset of various chronic diseases, including cardiac disease, obesity, inflammatory bowel disease, several cancers, and type 2 diabetes. The review provides an updated knowledge base about the scientific literature addressing how fermented foods influence the consumer microbiome and promote good health with prevention of non-communicable diseases. In addition, the review proves that the consumption of fermented foods affects gastrointestinal flora in the short and long term and can be considered an important part of the diet.

Distribution, Antioxidant Capacity, Bioavailability and Biological Properties of Anthocyanin Pigments in Blood Oranges and Other Citrus Species

Anthocyanins are natural pigments that give a red, purple, and blue color to many plant, flower, fruit, and vegetable species. Their presence within the genus Citrus was first reported in 1916, and it is well-known that the red color of the flesh and rind of blood (red or pigmented) oranges (Citrus sinensis L. Osbeck) is due to the presence of anthocyanins. They are also present in the young shoots, flowers, and peel of lemon (Citrus limon (L.) Burm. f.), citron (Citrus medica L.), and other citrus species. Since then, the scientific community has expressed increasing interest in studying their profile and distribution, with many published studies focused on the quali-quantitative pattern in the different vegetative tissues belonging to the genus Citrus. Moreover, with the discovery of their relevant antioxidant activity, owing to their ability to capture free radicals, much research has been performed in the last two decades on their radical scavenging power, in vitro and in vivo biological properties, and anticarcinogenic capacity, also focusing attention on their bioavailability for humans. The present work is intended as a comprehensive review of the advances in scientific research on anthocyanin pigments naturally occurring within the genus Citrus, including their natural distribution, antioxidant capacity, bioavailability, and biological value and properties. The scientific evidence herein reported can be used to further increase the knowledge of this class of compounds and represents a valuable and comprehensive contribution to promoting anthocyanin-rich citrus fruit consumption as a healthy dietary habit.

Sulfation of Phenolic Acids: Chemoenzymatic vs. Chemical Synthesis

Phenolic acids are known flavonoid metabolites, which typically undergo bioconjugation during phase II of biotransformation, forming sulfates, along with other conjugates. Sulfated derivatives of phenolic acids can be synthesized by two approaches: chemoenzymatically by 3'-phosphoadenosine-5'-phosphosulfate (PAPS)-dependent sulfotransferases or PAPS-independent aryl sulfotransferases such as those from Desulfitobacterium hafniense, or chemically using SO₃ complexes. Both approaches were tested with six selected phenolic acids (2-hydroxyphenylacetic acid (2-HPA), 3-hydroxyphenylacetic acid (3-HPA), 4-hydroxyphenylacetic acid (4-HPA), 3,4-dihydroxyphenylacetic acid (DHPA), 3-(4-hydroxyphenyl)propionic acid (4-HPP), and 3,4-dihydroxyphenylpropionic acid (DHPP)) to create a library of sulfated metabolites of phenolic acids. The sulfates of 3-HPA, 4-HPA, 4-HPP, DHPA, and DHPP were all obtained by the methods of chemical synthesis. In contrast, the enzymatic sulfation of monohydroxyphenolic acids failed probably due to enzyme inhibition, whereas the same reaction was successful for dihydroxyphenolic acids (DHPA and DHPP). Special attention was also paid to the counterions of the sulfates, a topic often poorly reported in synthetic works. The products obtained will serve as authentic analytical standards in metabolic studies and to determine their biological activity.

The Impact of Dietary Flavonols on Central Obesity Parameters in Polish Adults

Background: Central obesity is defined as the excessive fat tissue located in abdominal region accompanied by systemic inflammation, which drives to cardiovascular disease. Flavonols are antioxidative agents present in food. The aim of this study was investigating the relationship between dietary flavonols intake and central obesity. Methods and results: 80 participants (40 central obese and 40 healthy controls) were administered a food frequency questionnaire dedicated to flavonols intake assessment. Body composition was measured with bioelectrical impedance analysis. The analysis showed significant differences between central obese participants and healthy controls in total flavonol (p = 0.005), quercetin (p = 0.003), kaempferol (p = 0.04) and isorhamnetin (p < 0.001) habitual intake. Among central obese participants, there was a moderate inverse correlation between fat mass (FM) and total flavonol (R = −0.378; 95% CI: −0.620 to −0.071; p = 0.02), quercetin (R = −0.352; 95% CI: −0.601 to −0.041; p = 0.03), kaempferol (R = −0.425; 95% CI: −0.653 to −0.127; p = 0.01) and myricetin intake (R = −0.352; 95% CI: −0.601 to −0.041; p = 0.03). BMI was inversely correlated with total flavonol (R = −0.330; 95% CI: −0.584 to −0.016; p = 0.04) and quercetin intake (R = −0.336; 95% CI: −0.589 to −0.023; p = 0.04). Waist circumference was inversely correlated with total flavonol (R = −0.328; 95% CI: −0.586 to −0.009; p = 0.04), quercetin (R = −0.322; 95% CI: −0.582 to −0.002; p = 0.048) and myricetin intake (R = −0.367; 95% CI: −0.615 to −0.054; p = 0.02). Among flavonols’ dietary sources, there was an inverse correlation between black tea consumption and FM (R: −0.511; 95% CI: −0.712 to −0.233; p < 0.001) and between coffee and waist circumference (R: −0.352; 95% CI: −0.604 to −0.036; p = 0.03) in central obese participants. Conclusions: The higher flavonol intake could play a protective role in abdominal obesity development. What is more, total and selected flavonol dietary intakes are inversely correlated with the parameters used for obesity assessment in central obese participants. The habitual consumption of products rich in flavonols, mainly tea and coffee, could possibly have a preventive role in abdominal obesity development.

Dietary Isorhamnetin Intake Is Associated with Lower Blood Pressure in Coronary Artery Disease Patients

Background: Recent studies suggest the positive role of flavonols on blood pressure (BP) values, although there are not many conducted on humans. The aim of this study was to examine the relationship between flavonol intake and their main sources of consumption, and systolic (SBP) and diastolic (DBP) BP values in coronary artery disease (CAD) patients. Methods and results: forty CAD patients completed a food-frequency questionnaire dedicated to flavonol-intake assessment. The analysis revealed significant correlation between isorhamnetin intake and SBP values—absolute (R: −0.36; 95% CI: −0.602 to −0.052; p = 0.02), and related to body mass (R: −0.38; 95% CI: −0.617 to −0.076; p = 0.02. This effect was observed in male participants (R: −0.65; 95% CI: −0.844 to −0.302; p = 0.001 and R: −0.63; 95% CI: −0.837 to −0.280; p = 0.002 respectively), but not in female patients. The main contributors were onions, tomatoes, blueberries, apples, tea, coffee and wine. White onion (R: −0.39; 95% CI: −0.624 to −0.088; p = 0.01) consumption was inversely correlated with SBP, and tomato consumption (R: −0.33; 95% CI: −0.581 to −0.020; p = 0.04) with DBP. The comparison between patients with BP < 140 mmHg and ≥140 mmHg revealed significant differences in white onion (p = 0.01) and blueberry (p = 0.04) intake. Conclusions: This study revealed the relationship between long-term dietary isorhamnetin intake and SBP values. The analysis of specific food intake showed that onion, tomato and blueberry consumption could impact BP values. This may suggest that a dietary approach which includes a higher intake of isorhamnetin-rich products could possibly result in BP lowering in CAD patients.

Bioactivity and Therapeutic Potential of Kaempferol and Quercetin: New Insights for Plant and Human Health

Plant secondary metabolites, especially flavonoids, are major metabolites widely found in plants that play several key roles in plant defence and signalling in response to stress conditions. The most studied among these flavonoids are kaempferol and quercetin due to their anti-oxidative potential and their key roles in the defence system, making them more critical for plant adaptation in stress environments. Kaempferol and quercetin in plants have great therapeutic potential for human health. Despite being well-studied, some of their functional aspects regarding plants and human health need further evaluation. This review summarizes the emerging potential of kaempferol and quercetin in terms of antimicrobial activity, bioavailability and bioactivity in the human body as well as in the regulation of plant defence in response to stresses and as a signalling molecule in terms of hormonal modulation under stress conditions. We also evaluated the safe use of both metabolites in the pharmaceutical industry.

Dietary Isorhamnetin Intake Is Inversely Associated with Coronary Artery Disease Occurrence in Polish Adults

The role of antioxidative agents in coronary artery disease (CAD) has been investigated, but the analysis of specific flavonols intake in Polish adults requires validated tools. The aim of this study was to estimate the dietary intake of flavonols in CAD patients by creating a food frequency questionnaire (FFQ) dedicated for this purpose in Polish adults. The FFQ included 140 products from 12 food groups. The study involved 103 adult respondents (43 CAD patients and 60 healthy controls). Mean daily intakes of total flavonols, quercetin, kaempferol, myricetin and isorhamnetin were calculated as absolute values and quartiles. Mean daily intakes of 12 main food categories and 27 subcategories were calculated as portions and quartiles. The validity test revealed high correlation for total flavonols, kaempferol, myricetin and isorhamnetin and moderate for quercetin. In the reproducibility analysis, the correlation was high for total flavonols, quercetin, kaempferol and myricetin, moderate for isorhamnetin and high for all 12 categories and 25 out of 27 subcategories of the tested food groups. The application of the FFQ in healthy adults and CAD patients revealed that dietary intakes of total flavonols and proportional intakes of kaempferol and isorhamnetin in Polish adults and CAD patients are higher than in most other European countries, while the proportional intakes of quercetin and myricetin are lower than in most European countries. The comparison between CAD patients and the healthy controls revealed significant differences in dietary isorhamnetin intake (p = 0.002). The results suggest that dietary isorhamnetin could have a potential role in CAD prevention.

Total dietary flavonoid intake and risk of cardiometabolic diseases: A dose-response meta-analysis of prospective cohort studies

Several epidemiological studies have suggested that flavonoid intake is associated with a decreased risk of cardiometabolic disease. However, the results remained inconsistent and there is no dose-response meta-analysis for specific outcomes. We conducted a meta-analysis to synthesize the knowledge about their associations and to explore their dose-response relationships. We comprehensively searched the PubMed, Embase, and Web of Science databases for prospective cohort studies published up to December 1, 2021. Summary relative risks (RR) and 95% confidence intervals (CI) were pooled for the association between flavonoid intake and cardiometabolic disease. Evaluations of linear or nonlinear dose-response were presented by restricted cubic splines. We identified 47 articles, including 1,346 676 participants and 127,507 cases in this meta-analysis. The summary of RR per 500 mg/d increase in flavonoid intake was 0.93 (95% CI 0.88-0.98) for cardiovascular disease, 0.89 (95% CI 0.84-0.94) for diabetes, and 0.97 (95% CI 0.94-0.99) for hypertension, respectively. We also found a linearity dose-response association between total flavonoid intake and cardiovascular disease (p nonlinearity = 0.541), and diabetes (p nonlinearity = 0.077). Our finding based on quantitative data suggested that a higher level of flavonoid intake is beneficial for the prevention of cardiometabolic diseases.

Effects of the Treatment with Flavonoids on Metabolic Syndrome Components in Humans: A Systematic Review Focusing on Mechanisms of Action

Diets high in bioactive compounds, such as polyphenols, have been used to mitigate metabolic syndrome (MetS). Polyphenols are a large group of naturally occurring bioactive compounds, classified into two main classes: non-flavonoids and flavonoids. Flavonoids are distributed in foods, such as fruits, vegetables, tea, red wine, and cocoa. Studies have already demonstrated the benefits of flavonoids on the cardiovascular and nervous systems, as well as cancer cells. The present review summarizes the results of clinical studies that evaluated the effects of flavonoids on the components of the MetS and associated complications when offered as supplements over the long term. The results show that flavonoids can significantly modulate several metabolic parameters, such as lipid profile, blood pressure, and blood glucose. Only theaflavin and catechin were unable to affect metabolic parameters. Moreover, only body weight and body mass index were unaltered. Thus, the evidence presented in this systematic review offers bases in support of a flavonoid supplementation, held for at least 3 weeks, as a strategy to improve several metabolic parameters and, consequently, reduce the risk of diseases associated with MetS. This fact becomes stronger due to the rare side effects reported with flavonoids.

Higher habitual dietary flavonoid intake associates with lower central blood pressure and arterial stiffness in healthy older adults

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.

Identification of CaAN3 as a fruit-specific regulator of anthocyanin biosynthesis in pepper (Capsicum annuum)

The novel gene CaAN3 encodes an R2R3 MYB transcription factor that regulates fruit-specific anthocyanin accumulation. The key regulatory gene CaAN2 encodes an R2R3 MYB transcription factor that regulates anthocyanin biosynthesis in various tissues in pepper (Capsicum annuum). However, CaAN2 is not expressed in certain pepper accessions showing fruit-specific anthocyanin accumulation. In this study, we identified the novel locus CaAN3 as a regulator of fruit-specific anthocyanin biosynthesis, using an F₂ population derived from a hybrid cultivar with purple immature fruits and segregating for CaAN3. We extracted total RNA, assembled two RNA pools according to fruit color, and carried out bulked segregant RNA sequencing. We aligned the raw reads to the pepper reference genome Dempsey and identified 6,672 significant single nucleotide polymorphisms (SNPs) by calculating the Δ(SNP-index) between the two pools. We then conducted molecular mapping to delimit the target region of CaAN3 to the interval 184.6-186.4 Mbp on chromosome 10. We focused on Dem.v1.00043895, encoding an R2R3 MYB transcription factor, as the strongest candidate gene. Sequence analysis revealed four insertion/deletion polymorphisms in the promoter region of the green CaAN3 allele. We employed virus-induced gene silencing and transient overexpression assays to characterize the function of the candidate gene. When Dem.v1.00043895 was silenced in pepper, anthocyanin accumulation decreased in the pericarp, while the transient overexpression of Dem.v1.00043895 in Nicotiana benthamiana leaves resulted in the accumulation of anthocyanins around the infiltration sites. These results showed that Dem.v1.00043895 is CaAN3, an activator of anthocyanin biosynthesis in pepper fruits.

The Role of Berry Consumption on Blood Pressure Regulation and Hypertension: An Overview of the Clinical Evidence

The existence of a relationship between the consumption of dietary berries and blood pressure reduction in humans has been repeatedly hypothesized and documented by an increasing body of epidemiological and clinical evidence that has accumulated in recent years. However, results are mixed and complicated by a number of potentially confounding factors. The objective of this article is to review and summarize the available clinical evidence examining the effects of berry consumption on blood pressure regulation as well as the prevention or treatment of hypertension in humans, providing an overview of the potential contribution of distinctive berry polyphenols (anthocyanins, condensed tannins and ellagic acid), and results of dietary interventions with blueberries, bilberries, cranberries, raspberries, strawberries, chokeberries, cherries, blackcurrants and açai berries. We conclude that, while there is insufficient evidence supporting the existence of a direct blood pressure lowering effect, there is stronger evidence for specific types of berries acting indirectly to normalize blood pressure in subjects that are already hypertensive.

Phytochemical index and hypertension in Korean adults using data from the Korea National Health and Nutrition Examination Survey in 2008-2019

BACKGROUND/OBJECTIVES

Although previous in vivo and in vitro studies have reported the beneficial effects of phytochemical-rich food on cardiovascular health, limited information is available regarding its' health effect on the community-dwelling population. This is especially true in Korea. Here, we examined the cross-sectional association between phytochemical levels and hypertension in Korean adults.

SUBJECTS/METHODS

We analyzed data from 38,198 Koreans aged ≥30 years who participated in the Korea National Health and Nutrition Examination Survey (2008-2019) and met the study's inclusion criteria. The Korean version of the Phytochemical Index (PI) was computed based on 24 h recall data. Hypertension was defined based on the American College of Cardiology/American Heart Association definition in 2017. Multivariate logistic regression analysis was used to examine the association between PI and hypertension.

RESULTS

In the multivariable adjusted model, participants in the highest PI quintile had a significantly low prevalence of hypertension (Odd ratio, 0.86; 95% confidence interval, 0.79-0.95). A dose-response analysis confirmed the inverse linearity between PI and hypertension (p for nonlinearity = 0.2634).

CONCLUSIONS

Consumption of phytochemical-rich foods may lower the prevalence of hypertension. A large-scale, prospective cohort study is required to validate these findings.

Effect of cocoa flavanol supplementation for the prevention of cardiovascular disease events: the COcoa Supplement and Multivitamin Outcomes Study (COSMOS) randomized clinical trial

BACKGROUND

Cocoa extract is a source of flavanols that favorably influence vascular risk factors in small and short-term trials, yet effects on clinical cardiovascular events are untested.

OBJECTIVES

We examined whether cocoa extract supplementation decreases total cardiovascular disease (CVD) among older adults.

METHODS

We conducted a randomized, double-blind, placebo-controlled, 2-by-2 factorial trial of cocoa extract supplementation and multivitamins for prevention of CVD and cancer among 21,442 US adults (12,666 women aged ≥65 y and 8776 men aged ≥60 y), free of major CVD and recently diagnosed cancer. The intervention phase was June 2015 through December 2020. This article reports on the cocoa extract intervention. Participants were randomly assigned to a cocoa extract supplement [500 mg flavanols/d, including 80 mg (-)-epicatechin] or placebo. The primary outcome was a composite of confirmed incident total cardiovascular events, including myocardial infarction (MI), stroke, coronary revascularization, cardiovascular death, carotid artery disease, peripheral artery surgery, and unstable angina.

RESULTS

During a median follow-up of 3.6 y, 410 participants taking cocoa extract and 456 taking placebo had confirmed total cardiovascular events (HR: 0.90; 95% CI: 0.78, 1.02; P = 0.11). For secondary endpoints, HRs were 0.73 (95% CI: 0.54, 0.98) for CVD death, 0.87 (95% CI: 0.66, 1.16) for MI, 0.91 (95% CI: 0.70, 1.17) for stroke, 0.95 (95% CI: 0.77, 1.17) for coronary revascularization, neutral for other individual cardiovascular endpoints, and 0.89 (95% CI: 0.77, 1.03) for all-cause mortality. Per-protocol analyses censoring follow-up at nonadherence supported a lower risk of total cardiovascular events (HR: 0.85; 95% CI: 0.72, 0.99). There were no safety concerns.

CONCLUSIONS

Cocoa extract supplementation did not significantly reduce total cardiovascular events among older adults but reduced CVD death by 27%. Potential reductions in total cardiovascular events were supported in per-protocol analyses. Additional research is warranted to clarify whether cocoa extract may reduce clinical cardiovascular events. This trial is registered at www.clinicaltrials.gov as NCT02422745.

The Effects of Berry Polyphenols on the Gut Microbiota and Blood Pressure: A Systematic Review of Randomized Clinical Trials in Humans

Berry consumption has beneficial effects on blood pressure. Intestinal microbiota transform berry phytochemicals into more bioactive forms. Thus, we performed a systematic review of randomized clinical trials to determine whether berry polyphenols in foods, extracts or supplements have effects on both the profile of gut microbiota and systolic and diastolic blood pressure in humans. PubMed, Cochrane Library, Scopus, and CAB Abstracts (EBSCOhost) were searched for randomized clinical trials in humans published from 1 January 2011 to 29 October 2021. Search results were imported into Covidence for screening and data extraction by two blinded reviewers, who also performed bias assessment independently. The literature search identified 216 publications; after duplicates were removed, 168 publications were screened with 12 full-text publications assessed for eligibility. Ultimately three randomized clinical trials in humans met the eligibility criteria. One randomized clinical trial showed a low risk of bias while the other two randomized clinical trials included low, high or unclear risk of bias. Together the randomized clinical trials showed that berry consumption (Aronia berry, strawberries, raspberries, cloudberries and bilberries) for 8–12 weeks had no significant effect on both blood pressure and the gut microbiota. More randomized clinical trials are needed to determine the effects of berry consumption on the profile of gut microbiota and blood pressure in humans.

The Impact of Flavonols on Cardiovascular Risk

Cardiovascular disease (CVD) is the leading cause of deaths globally. The main target for prevention of cardiovascular (CV) risk are lifestyle changes, including particular dietary recommendations, involving high intake of fruits and vegetables. Flavonols are a subgroup of flavonoids—compounds present in fruits, vegetables, and tea—known for their antioxidative properties. There are many findings about the beneficial impact of flavonols on general CV risk and its factors, but mainly from in vitro and animal model studies. This paper summarizes data from human studies about flavonols’ impact on general CV risk and its factors. A high dietary intake of flavonols could decrease CVD mortality directly or through impact on selected CV factors; however, available data are inconsistent. Nonetheless, specific groups of patients (smoking men, hypertensive and diabetic patients) can potentially benefit from selected dietary modifications or flavonols (quercetin) supplementation. Future investigations about kaempferol and myricetin are needed.

Flavonoids for depression and anxiety: a systematic review and meta-analysis

Natural flavonoids are the most plentiful form of polyphenols. Given the anti-inflammatory and antioxidant properties of flavonoids, researchers discovered that it might be effective in treating depression and anxiety. The effect of flavonoids on depression and anxiety was investigated by a meta-analysis and systematic review. We searched PubMed, Embase, and Medline databases up to October 15, 2021. We selected 11 studies, among them, 10 studies were chosen to evaluate the depression effects of flavonoids and 7 studies were used to assess anxiety disorder. The meta-analysis showed that flavonoids have an overall significant effect on depression (p = 0.004, Hedge's g = -0.487, 95% CI -0.814 to -0.160) and anxiety (p = 0.006, Hedge's g = -0.741, 95% CI -1.266 to -0.217). Subgroup analysis indicated that the symptoms of depression were significantly improved in the studies when the dose of flavonoids was 50-100mg/day or the treatment duration was ≥8weeks. Anxiety symptoms were improved in the studies with the dose of flavonoids was ≥50mg/day. There was no evidence of publication bias. Our findings suggest that flavonoids might improve symptoms of depression and anxiety. However, a small number of participants and studies were included in this meta-analysis. Therefore, the results should be interpreted with caution.