Dietary polyphenol intake and their major food sources in the Mexican Teachers' Cohort

The association of dietary total flavonoids and their subclasses with the risk of type 2 diabetes: a prospective cohort study

BACKGROUND

Data from mechanistic studies suggest flavonoids may benefit glucose metabolism, but their associations with type 2 diabetes (T2D) remain unclear. This study examined the prospective associations of dietary intake of total, classes, and individual flavonoids, as well as their source foods, with T2D in the CArdioVascular disease Association Study (CAVAS).

METHODS

A total of 16,666 Korean men and women were enrolled at baseline, and 953 were newly diagnosed with T2D over a median follow-up of 5.96 years. Intake of flavonoids was cumulatively averaged using all food frequency questionnaires before the censoring events. A Poisson regression model was used to estimate incidence rate ratios (IRRs) and 95% confidence intervals (CIs).

RESULTS

Women with higher total flavonoid, flavonol, isoflavone, and proanthocyanidin intake had a lower risk of T2D (fourth vs. first quartile, IRR 0.62; 95% CI 0.44-0.89; P for linearity and non-linearity < 0.05 for total flavonoids), while in men, flavanones, anthocyanins, and proanthocyanidins, but not total flavonoids, were inversely associated with T2D risk (all P interaction for sex > 0.05). The key source foods contributing to flavonoid intake were also different between men and women, except for apples: tangerines and strawberries in men and green leafy vegetables and soy products in women.

CONCLUSIONS

A higher intake of total flavonoids, particularly from vegetables, soybeans, and apples, may be associated with lower risk of T2D in women. However, flavonoids from fruits, rather than total flavonoids, may be inversely associated in men. The association between flavonoid intake and the risk of T2D may be contingent upon the dietary sources of flavonoids consumed.

Higher Dietary Polyphenol Intake Is Associated With Lower Blood Inflammatory Markers

BACKGROUND

Evidence suggests a link between polyphenol intake and reduced incidence of several chronic diseases. This could arise through associations between polyphenol intake and reduced systemic oxidative stress and subsequent inflammation. However, confirming this association is difficult, as few large cohorts allow for comprehensive assessments of both polyphenol intake and markers of systemic inflammation.

OBJECTIVES

To address this, polyphenol intake was assessed in the UK-based Airwave cohort using 7-d diet diaries and data from Phenol-Explorer to test for associations between polyphenol intake and blood biomarkers of inflammation.

METHODS

Participants included 9008 males and females aged 17-74 y (median age: 42 y) whose data was included in a cross-sectional analysis. Phenol-Explorer was used to estimate individuals' polyphenol intake from diet data describing the consumption of 4104 unique food items. C-reactive protein (CRP) and fibrinogen were used as blood biomarkers of inflammation.

RESULTS

There were 448 polyphenols found in reported diet items. Median total polyphenol intake was 1536 mg/d (1058-2092 mg/d). Phenolic acids and flavonoids were the main types of polyphenols, and nonalcoholic beverages, vegetables, and fruit were the primary sources. Variation in energy-adjusted polyphenol intake was explained by age, sex, salary, body mass index, education level, smoking, and alcohol consumption. Linear regressions showed inverse associations between total daily intake and both CRP (β: -0.00702; P < 0.001) and fibrinogen (β: -0.00221; P = 0.038). Associations with specific polyphenol compound groups were also found. Logistic regressions using total polyphenol intake quartiles showed stepwise reductions in the odds of elevated CRP with higher intake (6%, 23%, and 24% compared with quartile 1; P = 0.003), alongside 3% and 7% lower odds per unit of polyphenol consumption equivalent to 1 cup of tea or coffee per day.

CONCLUSIONS

This study describes polyphenol intake in a large, contemporary UK cohort. We observed associations between higher intake and lower CRP and fibrinogen. This contributes to evidence supporting the health benefits of dietary polyphenols.

Dietary Intake of (Poly)phenols and Risk of All-Cause and Cause-Specific Mortality in the Mexican Teachers' Cohort Study

BACKGROUND

Observational studies have reported that total (poly)phenol intake is associated with a reduction in all-cause and cardiovascular mortality, but mainly from high-income countries, where (poly)phenol intake may differ from that of low- and middle-income countries.

OBJECTIVES

Our objective was to evaluate the association between the intake of total, all classes, and subclasses of (poly)phenols and risk of all-cause and cause-specific mortality in a Mexican cohort.

METHODS

We used data from the Mexican Teachers' Cohort, which included 95,313 adult females. After a median follow-up of 11.2 y, 1725 deaths were reported, including 674 from cancer and 282 from cardiovascular diseases. (Poly)phenol intake was estimated using a validated food frequency questionnaire and the Phenol-Explorer database. Multivariable Cox models were applied to estimate the association between (poly)phenol intake and all-cause mortality and competitive risk models for cause-specific mortality.

RESULTS

Comparing extreme quartiles, total (poly)phenol intake was associated with lower risk of all-cause [hazard ratio (HR)Q4vs.Q1: 0.88; 95% CI: 0.76, 0.99; P-trend = 0.01] and cancer mortality (HRQ4vs.Q1: 0.81; 95% CI: 0.64, 0.99; P-trend = 0.02). Among (poly)phenol classes, phenolic acids, particularly hydroxycinnamic acids from coffee, showed an inverse association with all-cause (HRQ4vs.Q1: 0.79; 95% CI: 0.69, 0.91; P-trend = 0.002) and cancer mortality (HRQ4vs.Q1: 0.75; 95% CI: 0.61, 0.94; P-trend = 0.03). No associations were observed with flavonoids or with cardiovascular mortality.

CONCLUSION

Our study suggests that high (poly)phenol intake, primarily consisting of phenolic acids such as hydroxycinnamic acids, may have a protective effect on overall and cancer mortality. Null associations for flavonoid intake might be due to the potential underestimation of their intake in this population.

[Design and validation of a self-reported dietary polyphenol intake frequency questionnaire.]

Introduction

Introduction: although there is evidence linking polyphenol consumption with better health outcomes, information on consumption patterns, particularly in Latin American countries, is scarce. Objective: to design and evaluate the validity of an online self-reported food frequency questionnaire to measure dietary total polyphenol intake in the Chilean adult population. Methods: the designed questionnaire (FFQ-P) was submitted to expert opinion for content validity coefficient estimation; then a pilot study was conducted in 47 adults who completed FFQ-P, in addition to a six-day food record as a reference method. Wilcoxon was applied in related samples, Spearman's correlation to determine the strength of association and Bland-Altman diagrams to examine the difference between methods. Results: content validity reflected concordant values for adequacy (0.94 ± 0.04) and relevance (0.93 ± 0.05). The percentage difference between both methods was 1.2 %, with greater variability observed in fruits (9 %) and alcoholic beverages (4 %). The Wilcoxon test showed no significant differences between food groups. Medium reliability was observed for vegetables, fruits, tea, and coffee (0.26 to 0.5) and moderate reliability for alcoholic beverages (0.5 to 0.75). The mean value of the difference was 9.8, being within a short distance of zero. Conclusion: FFQ-P is reliable for estimating polyphenol intake from fruits, vegetables, alcoholic beverages, tea, and coffee; however, the intake of non-alcoholic beverages, nuts and olives should be interpreted with reservation.

Low polyphenol intake among highly scholarity population: CUME cohort

In the absence of a recommendation for daily intake of phenolic compounds, to compare the intake of the main dietary polyphenols between populations is a really challenge. This study aimed to estimate the total dietary intake of polyphenols, classes and their food sources among Brazilian graduates and postgraduates. This was a cross-sectional study using baseline data from the Cohort of Universities of Minas Gerais (CUME project). Food consumption was assessed using a quantitative food frequency questionnaire with 144 food items. Polyphenol intake was estimated from the Phenol-Explorer and US Department of Agriculture database, and previous studies that evaluated the phenolic content of specific foods. A total of 4130 individuals of both sexes with a median age of 34 (18-86) years old were finally included. The median intake of total polyphenols adjusted for energy was 753.41 mg/day (interquartile range - IQR=461.80; p<0.001), and the most consumed classes were phenolic acids and flavonoids, with median intakes of 552.30 mg/d (IQR=429.78; p<0.001) and 154.70 mg/day (IQR=108.70; p<0.001), respectively. The main food sources of polyphenols were coffee, peanuts, beans, and fruits. A lower intake of total polyphenols and their classes was observed in a population with similar characteristics to those from developed countries. The results demonstrate the importance of disseminating nutritional information about foods, so that the consumption of natural foods is prioritized. New studies that evaluate the consumption of polyphenols and their impact on human health are recommended to establish a daily recommendation for the consumption of such compounds.

Plant-derived polyphenolic compounds: nanodelivery through polysaccharide-based systems to improve the biological properties

Plant-derived polyphenols are naturally occurring compounds widely distributed in plants. They have received greater attention in the food and pharmaceutical industries due to their potential health benefits, reducing the risk of some chronic diseases due to their antioxidant, anti-inflammatory, anticancer, cardioprotective, and neuro-action properties. Polyphenolic compounds orally administered can be used as adjuvants in several treatments but with restricted uses due to chemical instability. The review discusses the different structural compositions of polyphenols and their influence on chemical stability. Despite the potential and wide applications, there is a need to improve the delivery of polyphenolics to target the human intestine without massive chemical modifications. Oral administration of polyphenols is unfeasible due to instability, low bioaccessibility, and limited bioavailability. Nano-delivery systems based on polysaccharides (starch, pectin, chitosan, and cellulose) have been identified as a viable option for oral ingestion, potentiate biological effects, and direct-controlled delivery in specific tissues. The time and dose can be individualized for specific diseases, such as intestinal cancer. This review will address the mechanisms by which polysaccharides-based nanostructured systems can protect against degradation and enhance intestinal permeation, oral bioavailability, and the potential application of polysaccharides as nanocarriers for the controlled and targeted delivery of polyphenolic compounds.

Bioactive Compounds Intake of the Brazilian Population According to Geographic Region

Studies have been conducted in order to estimate bioactive compound consumption across populations, with substantial disparities according to the origin of the cohort examined. In this sense, Brazil is a continental country with marked differences in food plant availability across geographic regions. We aimed to estimate the bioactive compound intake according to Brazilian geographic region, as well as to determine the major contributors. Data were obtained from the National Dietary Survey 2017-2018, a cross-sectional population-based study including data on the individual food intake of 46,164 subjects aged ≥10 years. The consumption of polyphenols (total and classes) was significantly higher in the South compared with other regions (p = 0.0001). Total carotenoid intake was higher in the Midwest, followed by the Southeast (p = 0.0001). Tea was the main supplier of total polyphenol intake in the South, whereas coffee contributed the most to total polyphenol intake in other Brazilian regions. Açaí, caja juice, mango and corn were important suppliers of carotenoid intake in the North and Northeast. Bioactive compound intake presented variations according to Brazilian region, and individuals living in the South, Midwest and Southeast may experience higher bioactive-dense diets. We highlight the potential of many food plants for sustained explorations to the development of marketable products, possibly increasing the bioactive compound intake.

Valorization of polyphenolic compounds from food industry by-products for application in polysaccharide-based nanoparticles

In the last decades, evidence has indicated the beneficial properties of dietary polyphenols. In vitro and in vivo studies support that the regular intake of these compounds may be a strategy to reduce the risks of some chronic non-communicable diseases. Despite their beneficial properties, they are poorly bioavailable compounds. Thus, the main objective of this review is to explore how nanotechnology improves human health while reducing environmental impacts with the sustainable use of vegetable residues, from extraction to the development of functional foods and supplements. This extensive literature review discusses different studies based on the application of nanotechnology to stabilize polyphenolic compounds and maintain their physical-chemical stability. Food industries commonly generate a significant amount of solid waste. Exploring the bioactive compounds of solid waste has been considered a sustainable strategy in line with emerging global sustainability needs. Nanotechnology can be an efficient tool to overcome the challenge of molecular instability, especially using polysaccharides such as pectin as assembling material. Complex polysaccharides are biomaterials that can be extracted from citrus and apple peels (from the juice industries) and constitute promising wall material stabilizing chemically sensitive compounds. Pectin is an excellent biomaterial to form nanostructures, as it has low toxicity, is biocompatible, and is resistant to human enzymes. The potential extraction of polyphenols and polysaccharides from residues and their inclusion in food supplements may be a possible application to reduce environmental impacts and constitutes an approach for effectively including bioactive compounds in the human diet. Extracting polyphenolics from industrial waste and using nanotechnology may be feasible to add value to food by-products, reduce impacts on nature and preserve the properties of these compounds.

Association between Polyphenol Intake and Lipid Profile of Adults and Elders in a Northeastern Brazilian Capital

This research was aimed at evaluating the relationship between the estimated polyphenol intake and the atherogenic lipid profile in adult and elder residents in the city of Teresina, located in the Northeastern Region of Brazil. This study was a cross-sectional population-based survey with 501 adults and elders, conducted in Teresina, Brazil. Food intake was obtained by 24-h food recall. The estimated polyphenol intake was calculated by multiplying the food consumption data from the recall by the polyphenol content in the foods described in the Phenol-Explorer database. The mean intake of total polyphenols was 1006.53 mg/day. The phenolic acids was the class with the highest intake, followed by the flavonols. Coffee, beans and apples were the main foods contributing to the total polyphenol intake. In the individuals with elevated serum concentrations of total cholesterol and triglycerides, the intake of total polyphenols was significantly higher. The intake of total polyphenols, phenolic acids and lignans was higher in the subjects with dyslipidemia. This article provides, for the first time, data on the intake of the total polyphenol classes and subclasses in the evaluated population and the relationship with the lipid profile. The individuals with a higher intake of total polyphenols had a worse lipid profile, which may be a consequence of an improved diet in those individuals who present with dyslipidemia.

Descriptive analysis of dietary (poly)phenol intake in the subcohort MAX from DCH-NG: "Diet, Cancer and Health-Next Generations cohort"

PURPOSE

(Poly)phenols are bioactive compounds widely distributed in plant-based foods. Currently, limited data exist on the intake distribution of (poly)phenols across meals. This study aimed to estimate dietary intakes of all individual (poly)phenols and total intake per class and subclass by meal event, and to identify their main food sources in the subcohort MAX from the Diet, Cancer and Health-Next Generations cohort (DCH-NG).

METHODS

Dietary data were collected using three web-based 24-h dietary recalls over 1 year. In total, 676 participants completed at least one recall. The dietary data were linked to Phenol-Explorer database using standardized procedures and an in-house software. We categorized foods/drinks into five options of meal events selected by the participant: 'Breakfast', 'Lunch', 'Evening', 'Snack', and 'Drink'.

RESULTS

Adjusted total (poly)phenols mean intake by meal was the highest in the drink event (563 mg/day in men and 423 mg/day in women) and the lowest in the evening event (146 mg/day in men and 137 mg/day in women). The main overall (poly)phenol class contributor was phenolic acids (55.7-79.0%), except for evening and snack events where it was flavonoids (45.5-60%). The most consumed (poly)phenol subclasses were hydroxycinnamic acids and proanthocyanidins. Nonalcoholic beverages (coffee accounted for 66.4%), cocoa products, and cereals were the main food sources of total (poly)phenols.

CONCLUSION

This study provides data on the variability in the intake of classes and subclasses of (poly)phenols and their main food sources by meal event according to lifestyle data, age, and gender in a Danish population.

Differences in Metabolomic Profiles by Birthplace in Mexican-Origin Hispanic Men Who Participated in a Weight Loss Lifestyle Intervention

Birthplace, as a proxy for environmental exposures (e.g., diet), may influence metabolomic profiles and influence risk of cancer. This secondary analysis investigated metabolomic profile differences between foreign and U.S.-born Mexican-origin (MO) Hispanic men to shed light on potential mechanisms through which foreign- and U.S.-born individuals experience differences in cancer risk and risk factors. Plasma samples from MO Hispanic men (N = 42) who participated in a previous lifestyle intervention were collected pre-and post-intervention. Metabolomic profiles were characterized from samples using ultra performance liquid chromatography-quadrupole time of flight mass spectrometry (UPLC-QTOF). Models were visualized using supervised orthogonal projections to latent structures-discriminant analysis (OPLS-DA). Progenesis QI was used for peak integration and metabolite identification. Plasma metabolomic profiles differed between foreign- and U.S.-born pre-intervention (R2 = .65) and post-intervention (R2 = .62). Metabolomic profiles differed pre- versus post-intervention (R2 = .35 and R2 = .65) for the foreign- and U.S.-born group, respectively. Both endogenous metabolites and dietary components characterized differences between foreign- and U.S.-born participants pre- and post-intervention. Plasma metabolomic profiles from MO Hispanic men differed by birthplace. These results advance our understanding of relevant exposures that may affect cancer risk among MO Hispanic men born abroad or in the United States.

Estimated polyphenol intake and major food sources of the Brazilian population: changes between 2008–2009 and 2017–2018

Assessing the dietary intake of polyphenols and their major food sources is the first step towards documenting the associations with health outcomes. Considering recent changes in dietary patterns of the Brazilian population, continuous monitoring of polyphenol intake is important. Thus, the present study was conducted to estimate the polyphenol intake and major food sources in the diet of the Brazilian population using data from the most recent National Dietary Survey (NDS, 2017–2018), to characterise the intake changes according to demographic characteristics and to compare the intake over the past decade in Brazil. Data from two cross-sectional population-based surveys were analyzed in the study. Trends in polyphenol intake and major food sources were estimated using food consumption data from NDS 2008–2009 (n 34 003) and 2017–2018 (n 46 164). The median (25–75th percentiles) of energy-adjusted polyphenol intake in 2017–2018 was 216·3 mg (125·3–495·2 mg) per 1000 kcal/d (4184 kJ/d), representing an increase of 12·3 mg/d from 2008–2009. However, unadjusted polyphenol intakes were similar between the surveys (medians: 364·3 mg/d in 2008–2009 and 366·9 mg/d in 2017–2018). The main food sources of total and polyphenol intake classes presented some variations between 2008–2009 and 2017–2018, with greater contribution of beans preparations, salads and tea to polyphenol intake, and decrease of orange contribution. Our study provided an updated information on polyphenol intake and its major food sources. The median intake remains lower than the reported by other populations. Furthermore, the results may contribute to future studies investigating temporal trends in polyphenol intake and disease risk.

Changes in (poly)phenols intake and metabolic syndrome risk over ten years from adolescence to adulthood

BACKGROUND AND AIMS

(Poly)phenols might contribute to prevent cardiovascular disease, but limited prospective studies exist among adolescents. This study aimed to evaluate within-subject longitudinal changes in (poly)phenols intakes and food group contributors while also exploring the association with metabolic syndrome risk (MetS) during 10 years of follow up in European adolescents becoming young adults.

METHODS AND RESULTS

In 164 participants (58% girls, 13-18 y at baseline) from Ghent, Zaragoza and Lille, longitudinal data (2006-2016) on (poly)phenol intake was retrieved via 2 or 3 24 h recalls. Linear and logistic longitudinal regression tested the association of (poly)phenols intake (total and classes) with Mets risk or its components (waist-height-ratio, HDL cholesterol, LDL cholesterol, triglycerides, blood pressure and insulin resistance index), adjusted for age, sex, country and other nutrient intakes. The total (poly)phenols intake was 421 ± 107 mg/day (192 mg/1000 kcal/day) at baseline, while 610 ± 101 mg/day (311 mg/1000 kcal/day) at follow-up. The three major food sources for (poly)phenols were 'chocolate', 'fruit and vegetable juices', 'cakes and biscuits' during adolescence and 'coffee', 'tea' and 'chocolate' during adulthood. Phenolic acid intake was associated with less LDL increase over time, while stilbene intake with a steeper increase in triglycerides over time.

CONCLUSIONS

Differences in major (poly)phenols contributors over time were partially explained by age-specific dietary changes like increased coffee and tea during adulthood. Some significant (poly)phenols-MetS associations might argue for nutrition-based disease prevention during adolescence, especially since adolescents had low (poly)phenols intake.

Lignan exposure: a worldwide perspective

Dietary lignans are phytoestrogens that are mostly found in plant-based foods, especially whole grains, seeds, nuts, legumes and vegetables. An accurate assessment of lignan exposure is crucial to evaluate their potential health benefits and to establish future recommendations and dietary guidelines. This narrative review aimed to (i) summarize the pros and the cons of the current main assessment methods for lignan exposure─i.e., dietary questionnaires, food composition tables and biomarkers, (ii) describe the individual lignans more consumed from a worldwide perspective, as well as their main food sources, (iii) determine the lignans concentrations in both urine and blood, and explore their heterogeneity among countries, and finally (iv) discuss the main determinants of lignan exposure.

Effects of polyphenols in aging and neurodegeneration associated with oxidative stress

Aging is defined as the functional loss of tissues and organs over time. This is a biological, irreversible, progressive, and universal process that results from genetic and environmental factors, such as diet, physical activity, smoking, harmful alcohol consumption, and exposure to toxins, among others. Aging is a consequence of molecular and cellular damage built up over time. This damage begins with a gradual decrease in physical and mental capacity, thus increasing the risk of neurodegenerative diseases such as Alzheimer's and Parkinson's disease. Neuronal, functional, and structural damage can be explained by an imbalance among free radicals, reactive oxygen species, reactive nitrogen species, and antioxidants, which finally lead to oxidative stress. Due to the key role of free radicals, reactive oxygen species, and reactive nitrogen species, antioxidant therapy may reduce the oxidative damage associated with neurodegeneration. Exogenous antioxidants are molecules that may help maintain the balance between the formation and elimination of free radicals, thus protecting the cell from their toxicity. Among them, polyphenols are a broad group of secondary plant metabolites with potent antioxidant properties. Here, we review several studies that show the potential role of polyphenol consumption to prevent, or slow down, harmful oxidative processes linked to neurodegenerative disorders.

Estimated dietary polyphenol intake and major food sources of the Brazilian population

Epidemiological studies have suggested an inverse association between polyphenol intake and the risk of chronic diseases. However, the lack of comprehensive data on population-level intakes, especially in Latin American countries, has limited research on this topic. We aimed to estimate total and individual polyphenol intakes and determine the major dietary contributors in a representative sample of the Brazilian population. Data were obtained from the Brazilian Household Budget Survey, a cross-sectional survey which included data on individual food intake of 34 003 subjects aged 10 years and over collected using two 24-h dietary records. Polyphenol content of foods was identified using the Phenol-Explorer database and Brazilian Food Composition Database. Total and individual polyphenol intake was calculated, as well as the intake distribution by socio-demographic factors. The median and 25-75th percentiles of polyphenol intake were 364·3 and 200·9-1008 mg/d, respectively. After energy adjustment, the median and 25-75th percentiles of polyphenol intake were 204 and 111·4-542·1 mg/1000 kcal/d (4184 kJ/d), respectively. Non-alcoholic beverages and fruits were the major polyphenol suppliers, and coffee and orange juice the main individual food contributors to polyphenol intake. The individual compounds most consumed were isomers of chlorogenic acid (5-caffeoylquinic acid, 4-caffeoylquinic acid, 3-caffeoylquinic acid), naringenin and hesperetin. The present study provides, for the first time, data on dietary intake of total and individual polyphenols by the Brazilian population and illustrates the low quality of their diet. These results will facilitate the study of associations between polyphenol class intake and health outcomes, and will also be useful for future dietary intake recommendations.

Dietary flavonoid patterns and prostate cancer: evidence from a Mexican population-based case-control study

Flavonoids are a broad group of bioactive compounds with anticarcinogenic effects on the prostate that have been scarcely evaluated in Latin American populations. Our objective was to evaluate the association between dietary patterns of flavonoid intake and prostate cancer (PC) in a population-based case-control study carried out in Mexico City. Based on a semi-quantitative FFQ with a frame reference of 3 years before diagnosis or interview, we used an updated database for estimating the daily intake (mg/d) of flavones, flavonols and flavanols for 395 confirmed incident PC cases and 797 population controls matched by age (± 5 years). Histological PC differentiation was evaluated using the Gleason score at diagnosis. Flavonoid dietary intake patterns (FDIP) were determined through principal component analysis, and their association with PC was estimated using logistic regression models. Three FDIP were identified: gallate pattern (GP) characterised by (-)-epicatechin-3-O-gallate, (-)-epigallocatechin-3-O-gallate and (+)-gallocatechin; luteolin pattern (LP) characterised by luteolin and (-)-epigallocatechin-3-O-gallate; and a mixed pattern (MP) that included (+)-catechin, (-)-epicatechin and quercetin. A higher GP (ORT3 v.T1 = 0·47; 95 % CI 0·33, 0·66) and LP intake (ORT3 v. T1 = 0·39; 95 % CI 0·27, 0·59) were associated with a decreased PC likelihood. In contrast, a higher MP intake (ORT3 v. T1 = 2·32; 95 % CI 1·67, 3·23) increased PC likelihood. The possible differential and synergistic anticarcinogenic role of flavonoid compounds in PC deserves further study.

Assessment of dietary intake of bioactive food compounds according to income level in the Brazilian population

There is an inverse association between bioactive compounds intake and disease risk. The knowledge of its consumption according to socio-economic strata is important, which allows identification of potential intervention targets. Thus, we aimed to investigate bioactive compounds intake according to income level in Brazilian population. Data were obtained from the Brazilian Household Budget Survey, a cross-sectional survey which included data on individual food intake of 34,003 subjects aged 10 years and over collected using two 24-h dietary records. Polyphenol and carotenoid content of foods was identified using published databases. Total polyphenol and carotenoid intake were determined according to per capita income, as well as main food sources. Total polyphenols and flavonoids intake increased with income level, and subjects with lower income showed higher phenolic acids intake than individuals in highest income (p = 0.0001). Total carotenoids and classes intake (with exception to β-cryptoxanthin and zeaxanthin) were higher among subjects in highest income quartile, compared to the lowest quartile (p = 0.0001). Coffee was major source to total polyphenols and phenolic acids intake, and orange juice was main flavonoid provider in individuals from all income levels. In the upper income quartile, total carotenoid was supplied mainly by tomato and kale, and fruits had important contribution to carotenoid intake in the lowest income quartile. There is important influence of income level on diet quality regarding intake of foods with bioactive compounds, and individuals with lower income may experience lower quality diets due to less availability of foods with bioactive compounds.

Flavonoid-Based Cancer Therapy: An Updated Review

As cancers are one of the most important causes of human morbidity and mortality worldwide, researchers try to discover novel compounds and therapeutic approaches to decrease survival of cancer cells, angiogenesis, proliferation and metastasis. In the last decade, use of special phytochemical compounds and flavonoids was reported to be an interesting and hopeful tactic in the field of cancer therapy. Flavonoids are natural polyphenols found in plant, fruits, vegetables, teas and medicinal herbs. Based on reports, over 10,000 flavonoids have been detected and categorized into several subclasses, including flavonols, anthocyanins, flavanones, flavones, isoflavones and chalcones. It seems that the anticancer effect of flavonoids is mainly due to their antioxidant and anti inflammatory activities and their potential to modulate molecular targets and signaling pathways involved in cell survival, proliferation, differentiation, migration, angiogenesis and hormone activities. The main aim of this review is to evaluate the relationship between flavonoids consumption and cancer risk, and discuss the anti-cancer effects of these natural compounds in human cancer cells. Hence, we tried to collect and revise important recent in vivo and in vitro researches about the most effective flavonoids and their main mechanisms of action in various types of cancer cells.

Natural Phytochemicals as Novel Therapeutic Strategies to Prevent and Treat Parkinson's Disease: Current Knowledge and Future Perspectives

Parkinson's disease (PD) is the second-most common neurodegenerative chronic disease affecting both cognitive performance and motor functions in aged people. Yet despite the prevalence of this disease, the current therapeutic options for the management of PD can only alleviate motor symptoms. Research has explored novel substances for naturally derived antioxidant phytochemicals with potential therapeutic benefits for PD patients through their neuroprotective mechanism, targeting oxidative stress, neuroinflammation, abnormal protein accumulation, mitochondrial dysfunction, endoplasmic reticulum stress, neurotrophic factor deficit, and apoptosis. The aim of the present study is to perform a comprehensive evaluation of naturally derived antioxidant phytochemicals with neuroprotective or therapeutic activities in PD, focusing on their neuropharmacological mechanisms, including modulation of antioxidant and anti-inflammatory activity, growth factor induction, neurotransmitter activity, direct regulation of mitochondrial apoptotic machinery, prevention of protein aggregation via modulation of protein folding, modification of cell signaling pathways, enhanced systemic immunity, autophagy, and proteasome activity. In addition, we provide data showing the relationship between nuclear factor E2-related factor 2 (Nrf2) and PD is supported by studies demonstrating that antiparkinsonian phytochemicals can activate the Nrf2/antioxidant response element (ARE) signaling pathway and Nrf2-dependent protein expression, preventing cellular oxidative damage and PD. Furthermore, we explore several experimental models that evaluated the potential neuroprotective efficacy of antioxidant phytochemical derivatives for their inhibitory effects on oxidative stress and neuroinflammation in the brain. Finally, we highlight recent developments in the nanodelivery of antioxidant phytochemicals and its neuroprotective application against pathological conditions associated with oxidative stress. In conclusion, naturally derived antioxidant phytochemicals can be considered as future pharmaceutical drug candidates to potentially alleviate symptoms or slow the progression of PD. However, further well-designed clinical studies are required to evaluate the protective and therapeutic benefits of phytochemicals as promising drugs in the management of PD.

Flavonoids are promising safe therapy against COVID-19

Flavonoids are a class of phenolic natural products, well-identified in traditional and modern medicines in the treatment of several diseases including viral infection. Flavonoids showed potential inhibitory activity against coronaviruses including the current pandemic outbreak caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and designated as COVID-19. Here, we have collected all data related to the potential inhibitory mechanisms of flavonoids against SARS-CoV-2 infection and their significant immunomodulatory activities. The data were mapped and compared to elect major flavonoids with a promising role in the current pandemic. Further, we have linked the global existence of flavonoids in medicinal plants and their role in protection against COVID-19. Computational analysis predicted that flavonoids can exhibit potential inhibitory activity against SARS-CoV-2 by binding to essential viral targets required in virus entry and/ or replication. Flavonoids also showed excellent immunomodulatory and anti-inflammatory activities including the inhibition of various inflammatory cytokines. Further, flavonoids showed significant ability to reduce the exacerbation of COVID-19 in the case of obesity via promoting lipids metabolism. Moreover, flavonoids exhibit a high safety profile, suitable bioavailability, and no significant adverse effects. For instance, plants rich in flavonoids are globally distributed and can offer great protection from COVID-19. The data described in this study strongly highlighted that flavonoids particularly quercetin and luteolin can exhibit promising multi-target activity against SARS-CoV-2, which promote their use in the current and expected future outbreaks. Therefore, a regimen of flavonoid-rich plants can be recommended to supplement a sufficient amount of flavonoids for the protection and treatment from SARS-CoV-2 infection.

Evaluation of the potential of total proanthocyanidin content in feces as an intake biomarker

Due to the health benefits associated with proanthocyanidins (PAs), it is useful to identify dietary PA biomarkers that can be determined by simple methods. Since increased levels of circulating PA metabolites are associated with increased fecal PA content, this study explores the spectrophotometric measurement of fecal PA content and its use as a biomarker of PA intake. To this end, fecal PA content was measured using an adaptation of Porter's spectrophotometric method in samples from a preclinical study and an observational study. In the former, excretion of 250-400 mg PA polymer equivalents/100 g feces was observed during supplementation and the day after, together with a significant association (p < 0.05) between PA intake and the excretion of both intact PAs and some PA metabolites, i.e., (+)-catechin, (-)-epicatechin and syringic acid. No relationship between intake and excretion was found in the observational study, either for the entire group (mean excretion of 240 ± 226 mg PA polymer equivalents/100 g feces) or after stratification into tertiles of consumption. In conclusion, the spectrophotometric determination of total PA content in feces proved to be a valid compliance marker in a preclinical study, but it was not associated with PA intake in free-living subjects. The potential of total PA excretion in observational studies, determined in fecal samples collected the day before dietary recall or in several fecal samples from the same subject, remains to be elucidated, as does a complete validation of the method proposed here.

Validity of a food frequency questionnaire for the estimation of total polyphenol intake estimates and its major food sources in the Japanese population: the JPHC FFQ Validation Study

We examine the validity and reproducibility of a food frequency questionnaire (FFQ) in a subsample of participants in the Japan Public Health Center-based Prospective Cohort Study using a database of polyphenol-containing foods commonly consumed in the Japanese population. Participants of the validation study were recruited from two different cohorts. In Cohort I, 215 participants completed a 28-d dietary record (DR) and the FFQ, and in Cohort II, 350 participants completed DRs and the FFQ. The total polyphenol intake estimated from the 28-d DR and FFQ were log-transformed and adjusted for energy intake by the residual method. Spearman correlation coefficients (CCs) between estimates from the FFQ and 28-d DR as well as two FFQs administered at a 1-year interval were computed. Median intakes of dietary polyphenols calculated from the DRs were 1172 mg/d for men and 1024 mg/d for women in Cohort I, and 1061 mg/d for men and 942 mg/d for women in Cohort II. The de-attenuated CCs for polyphenol intake between the DR and FFQ were 0⋅47 for men and 0⋅37 for women in Cohort I and 0⋅44 for men and 0⋅50 for women in Cohort II. Non-alcoholic beverages were the main contributor to total polyphenol intake in both men and women, accounting for 50 % of total polyphenol intake regardless of cohort and gender, followed by alcoholic beverages and seasoning and spices in men, and seasoning and spices, fruits and other vegetables in women. The present study showed that this FFQ had moderate validity and reproducibility and is suitable for use in future epidemiological studies.

Association between dietary flavonoid intakes and C-reactive protein levels: a cross-sectional study in Taiwan

Although the intake of specific flavonoid-rich foods may reduce C-reactive protein (CRP) levels, the association between dietary flavonoid intakes and CRP is inconsistent. We aim to describe dietary flavonoid intakes in a Taiwanese nationally representative sample and to investigate the association between flavonoid intakes and CRP. We conducted a cross-sectional study based on 2592 adults from the Nutrition and Health Survey in Taiwan 2005–8. Flavonoid intakes were estimated by linking the 24-h dietary recall with the U.S. Department of Agriculture flavonoid database and divided into quartiles. Adjusted estimates of the flavonoid intakes for the continuous and binary (elevated CRP: >0⋅3 mg/dl) variables were performed by using general linear and logistic regression. We found that tea, orange, tofu and sweet potato leaves/water spinach constituted the major food items of the total flavonoid intake. The total flavonoid intake was lower among women and elderly. Compared with the lowest total flavonoid intake quartile, participants in higher quartiles were associated with a lower CRP status (adjusted odds ratio (OR): 0⋅61, 95 % confidence interval (CI): 0⋅44–0⋅86 for the highest quartiles). The trends were similar for flavonol and flavan-3-ol intakes. Compared with non-consumers, tea consumers were likely to have a lower CRP status (adjusted OR: 0⋅74, 95 % CI: 0⋅57–0⋅97). In brief, a higher total flavonoid intake and tea consumption were inversely associated with CRP levels, indicating that a high-flavonoid diet may contribute to anti-inflammatory effects. A Taiwanese flavonoid content table is necessary for conducting further studies related to flavonoids in Taiwan.

Dietary Assessment Methods to Estimate (Poly)phenol Intake in Epidemiological Studies: A Systematic Review

Nutritional epidemiological studies have frequently reported associations between higher (poly)phenol intake and a decrease in the risk or incidence of noncommunicable diseases. However, the assessment methods that have been used to quantify the intakes of these compounds in large-population samples are highly variable. This systematic review aims to characterize the methods used to assess dietary (poly)phenol intake in observational studies, report the validation status of the methods, and give recommendations on method selection and data reporting. Three databases were searched for publications that have used dietary assessment methods to measure (poly)phenol intake and 549 eligible full texts were identified. Food-frequency questionnaires were found to be the most commonly used tool to assess dietary (poly)phenol intake (73%). Published data from peer-reviewed journals were the major source of (poly)phenol content data (25%). An increasing number of studies used open-access databases such as Phenol-Explorer and USDA databases on flavonoid content since their inception, which accounted for 11% and 23% of the data sources, respectively. Only 16% of the studies reported a method that had been validated for measuring the target (poly)phenols. For future research we recommend: 1) selecting a validated dietary assessment tool according to the target compounds and target period of measurement; 2) applying and combining comprehensive (poly)phenol content databases such as USDA and Phenol-Explorer; 3) detailing the methods used to assess (poly)phenol intake, including dietary assessment method, (poly)phenol content data source; 4) follow the Strengthening the Reporting of Observational Studies in Epidemiology-Nutritional Epidemiology (STROBE-nut) framework; and 5) complementing dietary intake assessment based on questionnaires with measurement of (poly)phenols in biofluids using appropriate and validated analytical methods.

Dietary profile and phenolics consumption in university students from the Ningxia Hui Autonomous Region of China

Background

Polyphenol intake assessment is a first step for evaluating relationships between polyphenols and health-related outcomes. Ningxia Hui Autonomous Region is one of the minority areas in China, which is primarily consists of arid, dry desert.

Objectives

This study was to make assessment about phenolics intake by university students from Ningxia of China.

Methods

This study employed data from a cross-sectional survey conducted from February to June 2018 in Ningxia Hui Autonomous Region of Northwest China. A total of 413 undergraduate students (143 boys, 270 girls), mean age 20.6 years, participated in the study. Food-frequency consumption and anthropometric measurements were included in the survey. According to phenol-explorer website, the amount of different classes of phenolic compounds were established. Statistics analyses were conducted with IBM SPSS 20.0.

Results

Profile of the student subjects showed low weight (19.1%), overweight (6.8%) and obesity (0.5%). The mean value about phenolics intake was 1378 mg/day. The main polyphenols consumed were flavonoids (58.7% of total polyphenols), followed by phenolic acids (38.1%). Vegetables, fruits and cereals products were the most consumed foods, while infusions and sugar products were lower. Fruit was the main food sources of total polyphenols, especially apple (22.95%), orange juice (19.03%) and apple juice (3.93%).

Conclusions

This is the first study on the polyphenol intake of university students in Ningxia of China. The present results will be benefit for further investigation on the role of polyphenol intake against disease occurrence for this adults group.

Dietary Polyphenol Intake in US Adults and 10-Year Trends: 2007-2016

BACKGROUND

Polyphenols are a class of phytochemicals that have antioxidant, anti-inflammatory, anticancer, and antiviral properties. Previous research suggests that dietary polyphenol intake is protective against major chronic diseases. To our knowledge, no data on polyphenol intake for the US adult population are available.

OBJECTIVE

This study explored usual dietary polyphenol intake among US adults in 2013-2016 and examined trends in intake during 2007-2016 by demographic characteristics, and identified major dietary sources of polyphenols.

DESIGN

The National Health and Nutrition Examination Survey is a series of cross-sectional surveys representative of the civilian noninstitutionalized US population.

PARTICIPANTS/SETTING

This study included 9,773 adults aged 20 years and older.

MAIN OUTCOME MEASURES

Dietary and supplement data were obtained from two 24-hour dietary recalls. Polyphenol intake was estimated using the Phenol Explorer Database and adjusted for total energy intake.

STATISTICAL ANALYSIS PERFORMED

Usual intake was estimated both overall and by demographic characteristics using the National Cancer Institute method. Trends in intake on a given day over 10 years were evaluated using regression analysis. The complex survey design was incorporated in all analyses.

RESULTS

In 2013-2016, the usual intake of dietary polyphenols was a mean (standard error) of 884.1 (20.4) mg per 1,000 kcal/d. Polyphenol intake was higher in adults 40 years and older, women, non-Hispanic White adults, and college graduates. During 2007-2016, the mean daily polyphenol intake did not change significantly over time for overall and demographic groups. Main polyphenol classes consumed were phenolic acids (mean [standard error] of 1,005.6 [34.3] mg/d) and flavonoids (mean [standard error] of 379.1 [10.7] mg/d). Foods and beverages contributed 99.8% of polyphenol intake, with coffee (39.6%), beans (9.8%), and tea (7.6%) as major dietary contributors.

CONCLUSION

Findings from this study suggest that polyphenol intake is consistent with the low intake of fruits, vegetables, and whole grains in the US population, and provide more evidence of the need for increased consumption of these food groups.

Hydroxycinnamic acids and human health: recent advances

There is an urgent need to improve human diet globally. Compelling evidence gathered over the past several decades suggests that a suboptimal diet is associated with many chronic diseases and may be responsible for more deaths than any other risks worldwide. The main components in our diet that need higher intake are whole grains, fruit and vegetables, and nuts and seeds; all of these are important sources of dietary fiber and polyphenols. The health benefits of dietary fiber and polyphenols are also supported by several decades of valuable research. However, the conclusions drawn from interventional human trials are not straightforward and the action mechanisms in improving human health are not fully understood. Moreover, there is a great inter-individual variation caused by different individual capabilities of processing, absorbing and using these compounds effectively. Data on the bioavailability and bioefficacy of hydroxycinnamic acids (HCAs) are limited when compared to other classes of polyphenols (e.g. anthocyanins). This review aims to summarize the latest research advances related to HCA bioavailability and their biological effects revealed by epidemiological data, pre-clinical and clinical studies. Moreover, we aim to review the effects of HCAs on gut microbiota diversity and function and its respective influence on host health. © 2019 Society of Chemical Industry.

Health-Promoting Properties of Proanthocyanidins for Intestinal Dysfunction

The intestinal barrier is constantly exposed to potentially harmful environmental factors, including food components and bacterial endotoxins. When intestinal barrier function and immune homeostasis are compromised (intestinal dysfunction), inflammatory conditions may develop and impact overall health. Evidence from experimental animal and cell culture studies suggests that exposure of intestinal mucosa to proanthocyanidin (PAC)-rich plant products, such as grape seeds, may contribute to maintaining the barrier function and to ameliorating the pathological inflammation present in diet-induced obesity and inflammatory bowel disease. In this review, we aim to update the current knowledge on the bioactivity of PACs in experimental models of intestinal dysfunction and in humans, and to provide insights into the underlying biochemical and molecular mechanisms.

Dietary Flavonoids for Immunoregulation and Cancer: Food Design for Targeting Disease

Flavonoids, one of the most abundant phytochemicals in a diet rich in fruits and vegetables, have been recognized as possessing anti-proliferative, antioxidant, anti-inflammatory, and estrogenic activities. Numerous cellular and animal-based studies show that flavonoids can function as antioxidants by preventing DNA damage and scavenging reactive oxygen radicals, inhibiting formation of DNA adducts, enhancing DNA repair, interfering with chemical damage by induction of Phase II enzymes, and modifying signaling pathways. Recent evidence also shows their ability to regulate the immune system. However, findings from clinical trials have been mixed with no clear consensus on dose, frequency, or type of flavonoids best suited to elicit many of the beneficial effects. Delivery of these bioactive compounds to their biological targets through "targeted designed" food processing strategies is critical to reach effective concentration in vivo. Thus, the identification of novel approaches that optimize flavonoid bioavailability is essential for their successful clinical application. In this review, we discuss the relevance of increasing flavonoid bioavailability, by agricultural engineering and "targeted food design" in the context of the immune system and cancer.

Systematic Review on Polyphenol Intake and Health Outcomes: Is there Sufficient Evidence to Define a Health-Promoting Polyphenol-Rich Dietary Pattern?

Growing evidence support association between polyphenol intake and reduced risk for chronic diseases, even if there is a broad debate about the effective amount of polyphenols able to exert such protective effect. The present systematic review provides an overview of the last 10-year literature on the evaluation of polyphenol intake and its association with specific disease markers and/or endpoints. An estimation of the mean total polyphenol intake has been performed despite the large heterogeneity of data reviewed. In addition, the contribution of dietary sources was considered, suggesting tea, coffee, red wine, fruit and vegetables as the main products providing polyphenols. Total flavonoids and specific subclasses, but not total polyphenols, have been apparently associated with a low risk of diabetes, cardiovascular events and all-cause mortality. However, large variability in terms of methods for the evaluation and quantification of polyphenol intake, markers and endpoints considered, makes it still difficult to establish an evidence-based reference intake for the whole class and subclass of compounds. Nevertheless, the critical mass of data available seem to strongly suggest the protective effect of a polyphenol-rich dietary pattern even if further well targeted and methodologically sound research should be encouraged in order to define specific recommendations.

Dietary Flavonoids as Cancer Chemopreventive Agents: An Updated Review of Human Studies

Over the past few years, interest in health research has increased, making improved health a global goal for 2030. The purpose of such research is to ensure healthy lives and promote wellbeing across individuals of all ages. It has been shown that nutrition plays a key role in the prevention of some chronic diseases such as obesity, cardiovascular disease, diabetes, and cancer. One of the aspects that characterises a healthy diet is a high intake of vegetables and fruits, as both are flavonoid-rich foods. Flavonoids are one of the main subclasses of dietary polyphenols and possess strong antioxidant activity and anti-carcinogenic properties. Moreover, some population-based studies have described a relationship between cancer risk and dietary flavonoid intake. In this context, the goal of this review was to provide an updated evaluation of the association between the risk of different types of cancers and dietary flavonoid intake. We analysed all relevant epidemiological studies from January 2008 to March 2019 using the PUBMED and Web of Science databases. In summary, this review concludes that dietary flavonoid intake is associated with a reduced risk of different types of cancer, such as gastric, breast, prostate, and colorectal cancers.