Intake Of Flavonoid Subclasses Research Articles

Intake of dietary flavonoids in relation to bone loss among U.S. adults: a promising strategy for improving bone health.

Dietary flavonoids have been recommended for improving bone health due to their antioxidant, anti-inflammatory and osteogenic properties. However, the effectiveness of each flavonoid subclass in the prevention and treatment of osteoporosis remains controversial. The objective of the current study was to examine the association between the intake of flavonoid subclasses and bone loss in 10 480 U.S. adults in the National Health and Nutrition Examination Survey. We employed a multinomial logistic regression model to calculate the odds ratios (OR) and 95% confidence intervals (95% CI). The intake of flavones, isoflavones, and flavanones was beneficially associated with osteoporosis (ORQ5 vs. Q1 = 0.44; 95% CI: 0.30-0.64 for flavones; ORQ5 vs. Q1 = 0.53; 95% CI: 0.37-0.77 for isoflavones; ORQ5 vs. Q1 = 0.66; 95% CI: 0.45-0.97 for flavanones). A higher intake of flavones and flavanones was significantly associated with a lower risk of bone loss at the femoral neck rather than the lumbar spine. Notably, stratified analysis showed that genistein had a harmful association with osteopenia in the population with lower serum calcium levels, whereas it had a beneficial association with osteoporosis in the population with higher serum calcium levels. Multiple sensitivity analyses were performed to test the robustness of the results, including subgroup analysis, exclusion of individuals' use of anti-osteoporosis, corticosteroid, and estrogenic medications, adjusting more potential confounders and calculation of the E-value. Overall, incorporating this modifiable diet into an individual's lifestyle could provide potential possibilities to prevent and ameliorate osteoporosis.

Higher anthocyanin intake is associated with a lower risk of non-alcoholic fatty liver disease in the United States adult population.

Flavonoids are a class of plant chemicals known to have health-promoting properties, including six subclasses. Anthocyanin is one of the subclasses that have anti-inflammatory and antioxidant activities. However, the relationship between flavonoid subclass intake and the risk of non-alcoholic fatty liver disease (NAFLD) and liver fibrosis has not been verified in representative samples of the United States. This is a cross-sectional study based on the data from the National Health and Nutrition Examination Survey (NHANES) and the Food and Nutrient Database for Dietary Studies (FNDDS) in 2017-2018. The intake of flavonoid subclasses of the participants was obtained from two 24 h dietary recalls. The NAFLD and liver fibrosis were defined based on the international consensus criteria. The relationship between flavonoid subclass intake and NAFLD and liver fibrosis was evaluated using a multivariate logistic regression model corrected for multiple confounding factors. Subgroup analysis, trend tests, interaction tests and restricted cubic spline were carried out to further explore this relationship. In addition, we also explored the relationship between anthocyanin and liver serum biomarkers, dietary total energy intake and healthy eating index (HEI)-2015 scores. A total of 2,288 participants were included in the analysis. The intake of anthocyanin was significantly negatively associated with the risk of NAFLD, but not other flavonoid subclasses. A higher anthocyanin intake was significantly associated with a lower risk of NAFLD (quartile 4, OR 0.470, 95% CI 0.275-0.803). The results of subgroup analysis showed that the protective effect of dietary anthocyanin intake on NAFLD was more pronounced in participants of non-Hispanic whites, with hypertension and without diabetes (P for interaction <0.05). Alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), dietary total energy intake was significantly negatively correlated with dietary anthocyanin intake. We did not find any protective effect of flavonoid subclass intake on liver fibrosis. Anthocyanin, but not other flavonoid subclasses, can significantly reduce the risk of NAFLD. The protective effect was more pronounced in non-Hispanic whites, participants without diabetes and those with hypertension. Our study provides new evidence that anthocyanin intake has a reverse significant association with the risk for NAFLD.

Flavonoid intake and its correlation to malondialdehyde serum among reproductive-aged women with obesity

Background: Obesity modulates oxidative stress and can be detected by examining malondialdehyde (MDA) serum levels. Flavonoids are natural bioactive ingredients that can be found in various types of vegetables and fruits that function as antioxidants to suppress that oxidative stress.&#x0D; Objective: This study aimed to determine the correlation between flavonoid intake and MDA serum levels in obese women of reproductive age.&#x0D; Methods: This cross-sectional study was conducted in Kendari, Indonesia from April to October 2021. The purposive sampling method was used to obtain 88 subjects who met the research criteria. Data were collected through interviews covering flavonoids intake using validated SQ-FFQ. Anthropometric measurements were performed to assess nutritional status, and laboratory tests were applied to determine MDA serum levels.&#x0D; Results: The average intake of flavonoids in the subjects was 142,26 ± 56,53 mg per day. Meanwhile, the average MDA serum level in the subjects was 2.16 mol/L, ranging from 1.09 nmol/ml to 6.71 nmol/ml. There was no significant correlation between total flavonoid intake and MDA serum levels in obese women of reproductive age (r=0,188, p=0,079). However, there was a weak correlation between the intake of flavonoid subclasses, namely flavan-3-ols/flavanols and MDA serum levels (r=0.325, p=0.002).&#x0D; Conclusion: We conclude that there was no correlation between total flavonoid intake and MDA serum levels. However, there was a correlation between flavan-3-ols/flavanols and MDA serum levels in the subjects.

The role of the gut microbiome in the association between habitual anthocyanin intake and visceral abdominal fat in population-level analysis

ABSTRACTBackgroundFlavonoid intake modifies the composition of the gut microbiome, which contributes to the metabolism of flavonoids. Few studies have examined the contribution of the gut microbiome to the health benefits associated with flavonoid intake.ObjectivesWe aimed to examine associations between habitual intakes of flavonoid subclasses and MRI-determined visceral (VAT) and subcutaneous (SAT) adipose tissue. Uniquely, we also identified associations between the aforementioned measurements and gut microbiome composition sequenced from 16S ribosomal RNA genes.MethodsWe undertook cross-sectional analyses of 618 men and women (n = 368 male), aged 25–83 y, from the PopGen cohort.ResultsHigher intake of anthocyanins was associated with lower amounts of VAT [tertile (T)3-T1: −0.49 dm3; β: −8.9%; 95% CI: −16.2%, −1.1%; P = 0.03] and VAT:SAT ratio (T3-T1: −0.04; β: −7.1%; 95% CI: −13.5%, −0.3%; P = 0.03). Higher intakes of anthocyanin-rich foods were also inversely associated with VAT [quantile (Q)4-Q1: −0.39 dm3; β: −9.9%; 95% CI: −17.4%, −1.6%; P = 0.02] and VAT:SAT ratio (Q4-Q1: −0.04; β: −6.5%; 95% CI: −13.3%, −0.9%; P = 0.03). Participants with the highest intakes of anthocyanin-rich foods also had higher microbial diversity (Q4-Q1: β: 0.18; 95% CI: 0.06, 0.31; P < 0.01), higher abundances of Clostridiales (Q4-Q1: β: 449; 95% CI: 96.3, 801; P = 0.04) and Ruminococcaceae (Q4-Q1: β: 313; 95% CI: 33.6, 591; P = 0.04), and lower abundance of Clostridium XIVa (Q4-Q1: β: −41.1; 95% CI: −72.4, −9.8; P = 0.04). Participants with the highest microbial diversity, abundances of Clostridiales and Ruminococcaceae, and lower abundance of Clostridium XIVa had lower amounts of VAT. Up to 18.5% of the association between intake of anthocyanin-rich foods and VAT could be explained by the gut microbiome.ConclusionsThese novel data suggest that higher microbial diversity and abundance of specific taxa in the Clostridiales order may contribute to the association between higher intake of anthocyanins and lower abdominal adipose tissue.

Flavonoid Intake and Cardiovascular Disease Mortality Among US Adults, Data from Third National Health and Nutrition Examination Survey Linked Mortality File (P18-013-19)

ObjectivesThe objective of this research was to examine the association between total flavonoid intake and flavonoid sub-classes and CVD mortality among a nationally representative sample of US adults aged 40+ years at baseline and free of CVD. MethodsA nationally representative sample of adults from the NHANES III data (1988–1994; n = 7900; age > = 40 years) were matched with mortality data reported by the National Death Index through 2015 to examine associations between estimated usual intakes of total flavonoid intake and flavonoid sub-classes and CVD mortality. Cox Proportional Hazards regression models were constructed to estimate hazard ratios and 95% confidence intervals for CVD mortality. Up to four 24-hour recalls were used to estimate total flavonoid intake and flavonoid sub-class intake for participants at baseline. ResultsDuring a median follow-up of 17.9 years, there were 4245 death; 1629 CVD deaths (767 males, 862 females) documented. Mean flavonoid intake was 247.7 mg/day for males and 216 mg/day for males. We did not observe an inverse association between total flavonoid intake and CVD mortality for males (HR: 0.95, 95% CI 0.87, 1.03) or females (HR: 1.03, 95% CI 0.93, 1.14), after adjustments for demographic, lifestyle, clinical and dietary quality variables. We also did not find significant associations between intake of flavonoid sub-classes and CVD mortality. However, for males only, intake of flavanones was inversely associated with CVD mortality after adjustments for demographic variables, lifestyle, clinical variables and diet quality (HR: 0.93, 95% CI 0.87, 0.99, p-value < 0.04). ConclusionsIn this nationally representative study, with detailed information on flavonoid intake and CVD mortality data, we did not find an inverse association between total flavonoid intake and most flavonoid sub-classes and CVD mortality for adults aged 40+ years at baseline; however our findings do indicate a marginally significant inverse association between flavanone intake and CVD mortality for males only, after controlling for confounders. Funding SourcesNo funding sources to declare.

Dietary flavonoid intake in older adults: how many days of dietary assessment are required and what is the impact of seasonality?

BackgroundWithin- and between-person variation in nutrient intake is well established, but little is known about variability in dietary flavonoid intake, including the effect of seasonality.MethodsWithin- and between-individual variability of flavonoid intake, and intake of flavonoid subclasses was examined in older adults (n = 79; mean age 70.1 y (range: 60y-80y)), using three separate 4-day weighed food records (WFR) collected approximately 4 months apart. The effects of seasonality were also examined. Mixed-effects linear regression models were used to estimate within- and between-individual variance components for flavonoids and subclasses. The number of days of dietary assessment required for a high level of hypothetical accuracy was calculated from variance ratios.ResultsWithin- and between-individual variability was high for flavonoid intake, and intake of flavonoid subclasses, with variance ratios > 1. It was calculated that six days of WFR data are required for total flavonoid intake, and between 6 and 10 days was required for flavonoid subclasses. There was no effect of seasonality for total flavonoid intake or intake of flavonoid subclasses, with the exception that flavan-3-ol and flavanone intakes which were relatively low in summer, and in summer and winter, respectively.ConclusionWhile the effects of seasonality on total flavonoid intake may be small, within- and between-individual variation associated with flavonoid intake assessment appears to be substantial across 12 days of WFR data in older adults. It is recommended that a minimum of 6 days of weighed food records are collected to minimise the impact of within- and between-individual variability on total flavonoid intake assessments in this population.

Development, validation and reproducibility of a food frequency questionnaire to measure flavonoid intake in older Australian adults.

To develop and assess the validity and reproducibility of a food frequency questionnaire (FFQ) to measure total flavonoid intake, and individual flavonoid subclasses, in older adults. Retrospective analysis of flavonoid intake in older adults informed the development of a FFQ to measure flavonoid intake and determine the flavonoid subclasses consumed (anthocyanins, flavan-3-ols, flavones, flavonols and flavanones). Older adults (n = 42, mean age 75.3 ± 8.6 years) attended two interviews 1 month apart where anthropometrics (height and weight), blood pressure (BP), demographic data and a 93-item self-administered FFQ were collected. A 4-day food record (FR) was randomly administered between the two interview dates, and each food item was assigned a flavonoid and flavonoid subclass content using the United States Department of Agriculture flavonoid database. The criterion validity and reproducibility of the FFQ was assessed against a 4-day FR using the Wilcoxon signed-rank sum test, Spearman's correlation coefficient (r), Bland-Altman Plots and Cohen's kappa. Total flavonoid intake was determined (median intake FFQ = 919.3 mg/day, FR = 781.4 mg/day). Tests of validity indicated that the FFQ consistently overestimated total flavonoid intake compared with the 4-day FR. There was a significant difference in estimates between the FFQ and the 4-day FR for total flavonoid intake (Wilcoxon signed-rank sum P < 0.001; Bland-Altman plots indicated large bias and wide limits of agreement), but they were well correlated (Spearman's r 0.93, P < 0.001; Cohen's kappa κ = 0.619, P < 0.001). For individual flavonoid subclasses, the tests of validity indicated greater discrepancy compared with 4-day FR. The FFQ showed high reproducibility for estimating total flavonoid intake (FFQ1vsFFQ2: Wilcoxon signed-rank sum test, P > 0.05; Spearman's r 0.91, P < 0.001; Bland-Altman plots visually showed small, non-significant bias and wide limits of agreement; and Cohen's kappa κ = 0.619, P < 0.001), with a small mean percentage difference (6.7%). For individual flavonoid subclasses, the tests of reproducibility between FFQ1 and FFQ2 showed similarly high reproducibility. The developed FFQ appears suitable for satisfactorily ranking individuals according to total flavonoid intake. The FFQ shows limitations for estimating absolute total flavonoid intake and intake of flavonoid subclasses in comparison to a 4-day FR in terms of overestimating intake. Refinement and further validation of this tool may be required.

Abstract 2232: Dietary flavonoids, CYP1A1 genetic variants, and the risk of colorectal cancer

Abstract The role of dietary flavonoid intake in colorectal carcinogenesis might differ according to flavonoid subclasses and individual genetic variants related to carcinogen metabolism. Therefore, we examined whether greater habitual dietary intake of flavonoid subclasses was associated with a lower risk of colorectal cancer and whether CYP1A1 genetic variants altered this association. A semi-quantitative food frequency questionnaire was used to assess the dietary intake of six flavonoid subclasses (flavonols, flavonones, flavanones, flavan-3-ols, anthocyanidins, and isoflavones) in 923 patients with colorectal cancer and 1,846 controls; furthermore, CYP1A1 genetic variants (rs4646903 and rs1048943) were genotyped. A logistic regression was used to investigate dietary flavonoid intake, CYP1A1 genetic variants, and their interaction in relation to colorectal cancer risk. Among the subclasses of flavonoids, flavonols (OR [95% CI] = 0.10 [0.06, 0.16], highest vs. lowest quartile) and flavan-3-ols (OR [95% CI] = 0.54 [0.41, 0.71], highest vs. lowest quartile) were significantly associated with colorectal cancer risk after adjusting for confounders. Homozygous variants of CYP1A1 rs4646903 showed a protective effect on the risk of rectal cancer (OR [95% CI] = 0.60 [0.37, 0.96], CC vs. TT/TC). Carriers of the CC homozygous variant with high flavonol intake showed a greater decrease in colorectal cancer risk compared with T allele carriers with low flavonol intake (P for interaction = 0.02), particularly regarding rectal cancer (P for interaction = 0.005). In conclusion, the effect of dietary flavonoid intake on colorectal cancer risk differs by flavonoid subclasses and CYP1A1 genetic variants. Citation Format: Jeongseon Kim, Young Ae Cho, Jeonghee Lee, Jae Hwan Oh, Dae Kyung Sohn, Hee Jin Chang. Dietary flavonoids, CYP1A1 genetic variants, and the risk of colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2232. doi:10.1158/1538-7445.AM2017-2232

Dietary Flavonoids, CYP1A1 Genetic Variants, and the Risk of Colorectal Cancer in a Korean population

The role of dietary flavonoid intake in colorectal carcinogenesis might differ according to flavonoid subclasses and individual genetic variants related to carcinogen metabolism. Therefore, we examined whether greater dietary intake of flavonoid subclasses was associated with a lower risk of colorectal cancer and whether CYP1A1 genetic variants altered this association. A semi-quantitative food frequency questionnaire was used to assess the dietary intake of six flavonoid subclasses (flavonols, flavones, flavanones, flavan-3-ols, anthocyanidins, and isoflavones) in 923 patients with colorectal cancer and 1,846 controls; furthermore, CYP1A1 genetic variants (rs4646903 and rs1048943) were genotyped. Among the subclasses of flavonoids, higher intake of flavonols and flavan-3-ols showed a stronger association with a reduced risk of colorectal cancer after adjusting for potential confounding factors. Carriers of the CYP1A1 rs4646903 CC homozygous variant showed a reduced risk of rectal cancer compared with that in TT carriers. The inverse association between dietary flavonol intake and colorectal cancer risk was stronger among carriers of the CC homozygous variant than among T allele carriers (P for interaction = 0.02), particularly for rectal cancer (P for interaction = 0.005). In conclusion, the effect of dietary flavonoid intake on colorectal cancer risk differs according to flavonoid subclasses and CYP1A1 genetic variants.

Dietary intake of flavonoid subclasses and risk of colorectal cancer: evidence from population studies.

ObjectiveTo systematically evaluate the relationship between flavonoids intake and colorectal cancer risk by conducting a meta-analysis.ResultsOur meta-analysis included 18 studies involving 16,917 colorectal cancer cases in 559,486 participants in relations to flavonoids intake during six to twenty-six years of follow-up. Our results indicated that specific flavonoid subclasses, such as procyanidins (OR = 0.75; 95% CI, 0.66–0.86) and isoflavones (OR = 0.87; 95% CI, 0.78–0.98), showed protective effects against colorectal cancer risk. There was no enough evidence indicating that increased consumption of total flavonoids were significantly associated with reduced risk of colorectal cancer (OR = 0.94, 95% CI, 0.81–1.09). There was no publication bias across studies.MethodsWe performed a systematic search of PubMed, Web of Science and the Cochrane Library databases for relevant articles before December 2015. A random-effects model was used to estimate summary odds ratios and 95% confidence intervals (CIs) for associations between flavonoids and colorectal cancer risk. We assessed heterogeneity among studies by the Cochran Q and I2 statistics.ConclusionsOur meta-analysis provides comprehensive evidence and partly supported the hypothesis that higher habitual intake of foods rich in procyanidins and isoflavones may potentially decrease colorectal cancer incidence. More prospective studies are warranted to verify this protective association.

Habitual intake of flavonoid subclasses and risk of colorectal cancer in 2 large prospective cohorts

Background: Flavonoids inhibit the growth of colon cancer cells in vitro. In a secondary analysis of a randomized controlled trial, the Polyp Prevention Trial, a higher intake of one subclass, flavonols, was statistically significantly associated with a reduced risk of recurrent advanced adenoma. Most previous prospective studies on colorectal cancer evaluated only a limited number of flavonoid subclasses and intake ranges, yielding inconsistent results.Objective: In this study, we examined whether higher habitual dietary intakes of flavonoid subclasses (flavonols, flavones, flavanones, flavan-3-ols, and anthocyanins) were associated with a lower risk of colorectal cancer.Design: Using data from validated food-frequency questionnaires administered every 4 y and an updated flavonoid food composition database, we calculated flavonoid intakes for 42,478 male participants from the Health Professionals Follow-Up Study and for 76,364 female participants from the Nurses’ Health Study.Results: During up to 26 y of follow-up, 2519 colorectal cancer cases (1061 in men, 1458 in women) were documented. Intakes of flavonoid subclasses were not associated with risk of colorectal cancer in either cohort. Pooled multivariable adjusted RRs (95% CIs) comparing the highest with the lowest quintiles were 1.04 (0.91, 1.18) for flavonols, 1.01 (0.89, 1.15) for flavones, 0.96 (0.84, 1.10) for flavanones, 1.07 (0.95, 1.21) for flavan-3-ols, and 0.98 (0.81, 1.19) for anthocyanins (all P values for heterogeneity by sex >0.19). In subsite analyses, flavonoid intake was also not associated with colon or rectal cancer risk.Conclusion: Our findings do not support the hypothesis that a higher habitual intake of any flavonoid subclass decreases the risk of colorectal cancer.

DIETARY FLAVONOID INTAKE AND COGNITIVE PERFORMANCE IN OLDER ADULTS WITH ALZHEIMER’S TYPE DEMENTIA

Background: Dietary flavonoid intake and intake of flavonoid subclasses has been associated with improved cognitive performance. However, the association between flavonoid intake and cognitive performance in older adults with Alzheimer’s type dementia has not been investigated. Objectives: To estimate dietary total flavonoid intake and intake of flavonoid subclasses in older adults with Alzheimer’s type dementia and assess the relationship of flavonoid intake with measures of cognition. Design: Cross sectional analysis. Setting: Community dwelling older adults in NSW, Australia. Participants: Older adults (+65y) with mild to moderate dementia (n=49). Measurements: A 24h diet recall was collected with help from a carer and used to estimate flavonoid intake. A battery of cognitive tasks assessed cognitive performance of several cognitive domains. Results: Pearson and spearman correlation coefficients identified an association between flavonoid intake and executive function (r=0.319, p=0.025). After controlling for depression, the relationship was reduced. Conclusion: The identified association between cognitive functioning, depression and flavonoid intake in older adults with Alzheimer’s type dementia warrants further research in a larger sample.

Intakes of Anthocyanins and Flavones Are Associated with Biomarkers of Insulin Resistance and Inflammation in Women1,2

Although laboratory data suggest that several flavonoid subclasses are involved in glucose metabolism, limited clinical and epidemiologic data are available. The current study examined associations between habitual intake of flavonoid subclasses, insulin resistance, and related inflammatory biomarkers. In a cross-sectional study of 1997 females aged 18–76 y, intakes of total flavonoids and their subclasses (flavanones, anthocyanins, flavan-3-ols, polymeric flavonoids, flavonols, flavones) were calculated from food frequency questionnaires using an extended USDA database. Fasting serum glucose, insulin, high-sensitivity C-reactive protein (hs-CRP; n = 1432), plasminogen activator inhibitor-1 (n = 843), and adiponectin (n = 1452) concentrations were measured. In multivariable analyses, higher anthocyanin and flavone intake were associated with significantly lower peripheral insulin resistance [homeostasis model assessment of insulin resistance; quintile 5 (Q5) to Q1 = −0.1, P-trend = 0.04 for anthocyanins and flavones] as a result of a decrease in insulin concentrations (Q5–Q1 = −0.7 μU/mL, P-trend = 0.02 anthocyanins; Q5–Q1 = −0.5 μU/mL, P-trend = 0.02 flavones). Higher anthocyanin intake was also associated with lower hs-CRP concentrations (Q5–Q1 = −0.3 mg/L, P-trend = 0.04), whereas those in the highest quintile of flavone intake had improved adiponectin concentrations (Q5–Q1 = 0.7 μg/L, P-trend = 0.01). Anthocyanin-rich foods were also associated with lower insulin and inflammation levels. No significant associations were observed for total or other flavonoid subclasses. Higher intakes of both anthocyanins and flavones were associated with improvements in insulin resistance and hs-CRP. These associations were found with intakes readily achieved in the diet. The observed reduction in insulin concentrations was similar to that reported previously for other lifestyle factors. Dose–response trials are needed to ascertain optimal intakes for the potential reduction of type 2 diabetes risk.

Circulation: Clinical Summaries

<i>Circulation:</i> Clinical Summaries

High anthocyanin intake is associated with a reduced risk of myocardial infarction in young and middle-aged women.

Our current knowledge of modifiable risk factors to prevent myocardial infarction (MI) in young and middle-aged women is limited, and the impact of diet is largely unknown. Dietary flavonoids exert potential beneficial effects on endothelial function in short-term trials; however, the relationship between habitual intake and risk of MI in women is unknown. We followed up 93 600 women 25 to 42 years of age from the Nurses' Health Study (NHS) II who were healthy at baseline (1989) to examine the relationship between anthocyanins and other flavonoids and the risk of MI. Intake of flavonoid subclasses was calculated from validated food-frequency questionnaires collected every 4 years using an updated and extended US Department of Agriculture database. During 18 years of follow-up, 405 cases of MI were reported. An inverse association between higher intake of anthocyanins and risk of MI was observed (hazard ratio, 0.68; 95% confidence interval, 0.49-0.96; P=0.03, highest versus lowest quintiles) after multivariate adjustment. The addition of intermediate conditions, including history of hypertension, did not significantly attenuate the relationship (hazard ratio, 0.70; 95% confidence interval, 0.50-0.97; P=0.03). Combined intake of 2 anthocyanin-rich foods, blueberries and strawberries, tended to be associated with a decreased risk of MI (hazard ratio, 0.66; 95% confidence interval, 0.40-1.08) in a comparison of those consuming >3 servings a week and those with lower intake. Intakes of other flavonoid subclasses were not significantly associated with MI risk. A high intake of anthocyanins may reduce MI risk in predominantly young women. Intervention trials are needed to further examine the health impact of increasing intakes of commonly consumed anthocyanin-rich foods.

Habitual flavonoid intakes are positively associated with bone mineral density in women

Dietary flavonoids exert bone-protective effects in animal models, but there is limited information on the effect of different flavonoid subclasses on bone health in humans. The aim of this observational study was to examine the association between habitual intake of flavonoid subclasses with bone mineral density (BMD) in a cohort of female twins. A total of 3160 women from the TwinsUK adult twin registry participated in the study. Habitual intakes of flavonoids and subclasses (flavanones, anthocyanins, flavan-3-ols, polymers, flavonols, and flavones) were calculated from semiquantitative food frequency questionnaires using an updated and extended U.S. Department of Agriculture (USDA) database. Bone density was measured using dual-energy X-ray absorptiometry. In multivariate analyses, total flavonoid intake was positively associated with higher BMD at the spine but not at the hip. For the subclasses, the magnitude of effect was greatest for anthocyanins, with a 0.034 g/cm(2) (3.4%) and 0.029 g/cm(2) (3.1%) higher BMD at the spine and hip, respectively, for women in the highest intake quintile compared to those in the lowest. Participants in the top quintile of flavone intake had a higher BMD at both sites; 0.021 g/cm(2) (spine) and 0.026 g/cm(2) (hip). At the spine, a greater intake of flavonols and polymers was associated with a higher BMD (0.021 and 0.024 g/cm(2) , respectively), whereas a higher flavanone intake was positively associated with hip BMD (0.008 g/cm(2) ). In conclusion, total flavonoid intake was positively associated with BMD, with effects observed for anthocyanins and flavones at both the hip and spine, supporting a role for flavonoids present in plant-based foods on bone health. .

Habitual intake of flavonoid subclasses and incident hypertension in adults

Dietary flavonoids have beneficial effects on blood pressure in intervention settings, but there is limited information on habitual intake and risk of hypertension in population-based studies. We examined the association between habitual flavonoid intake and incident hypertension in a prospective study in men and women. A total of 87,242 women from the Nurses' Health Study (NHS) II, 46,672 women from the NHS I, and 23,043 men from the Health Professionals Follow-Up Study (HPFS) participated in the study. Total flavonoid and subclass intakes were calculated from semiquantitative food-frequency questionnaires collected every 4 y by using an updated and extended US Department of Agriculture database. During 14 y of follow-up, 29,018 cases of hypertension in women and 5629 cases of hypertension in men were reported. In pooled multivariate-adjusted analyses, participants in the highest quintile of anthocyanin intake (predominantly from blueberries and strawberries) had an 8% reduction in risk of hypertension [relative risk (RR): 0.92; 95% CI: 0.86, 0.98; P < 0.03] compared with that for participants in the lowest quintile of anthocyanin intake; the risk reduction was 12% (RR: 0.88; 95% CI: 0.84, 0.93; P < 0.001) in participants ≤60 y of age and 0.96 (0.91, 1.02) in participants >60 y of age (P for age interaction = 0.02). Although intakes of other subclasses were not associated with hypertension, pooled analyses for individual compounds suggested a 5% (95% CI: 0.91, 0.99; P = 0.005) reduction in risk for the highest compared with the lowest quintiles of intake of the flavone apigenin. In participants ≤60 y of age, a 6% (95% CI: 0.88, 0.97; P = 0.002) reduction in risk was observed for the flavan-3-ol catechin when the highest and the lowest quintiles were compared. Anthocyanins and some flavone and flavan-3-ol compounds may contribute to the prevention of hypertension. These vasodilatory properties may result from specific structural similarities (including the B-ring hydroxylation and methyoxylation pattern).