title: Higher dietary anthocyanin and flavonol intakes are associated with anti-inflammatory effects in a population of US adults.
abstract: BACKGROUND
  Although growing evidence from trials and population-based studies has supported a protective role for flavonoids in relation to risk of certain chronic diseases, the underlying mechanisms remain unclear. Several previous studies focused on individual inflammatory biomarkers, but because of the limited specificity of any individual marker, an assessment of a combination of biomarkers may be more informative.
  
  
  OBJECTIVE
  We used an inflammation score (IS) that integrated 12 individual inflammatory biomarkers for the examination of associations with intakes of different flavonoid classes.
  
  
  METHODS
  The study was a cross-sectional analysis of 2375 Framingham Heart Study Offspring Cohort participants. Intakes of total flavonoids and their classes (anthocyanins, flavonols, flavanones, flavan-3-ols, polymers, and flavones) were calculated from validated food-frequency questionnaires. Individual inflammatory biomarkers were ranked, standardized, and summed to derive an overall IS and subgroup scores of functionally related biomarkers.
  
  
  RESULTS
  In multivariate analyses, an inverse association between higher anthocyanin and flavonol intakes and IS was observed with a mean ± SE difference between quintile categories 5 and 1 of -1.48 ± 0.32 (P-trend ≤ 0.001) and -0.72 ± 0.33 (P-trend = 0.01), respectively. Results remained significant after additional adjustment for physical activity and vitamin C and fruit and vegetable intakes. Higher anthocyanin intake was inversely associated with all biomarker subgroups, whereas higher flavonol intake was associated only with lower cytokine and oxidative stress biomarker concentrations. In food-based analyses, higher intakes of apples and pears, red wine, and strawberries were associated with a lower IS with differences between quintiles 5 and 1 of -1.02 ± 0.43 (P = 0.006), -1.73 ± 0.39 (P < 0.001), and -0.44 ± 0.88 (P = 0.02), respectively. Although intakes of other classes were not associated with a reduction in overall IS, higher intakes of flavan-3-ols and their polymers were associated with a significant reduction in oxidative stress biomarkers.
  
  
  CONCLUSIONS
  These findings provide evidence to suggest that an anti-inflammatory effect may be a key component underlying the reduction in risk of certain chronic diseases associated with higher intakes of anthocyanins and flavonols. The Framingham Offspring Study was registered at clinicaltrials.gov as NCT00005121 (Framingham Heart Study).
authors.affiliation: Department of Nutrition, Norwich Medical School, University of East Anglia, Norwich, United Kingdom;
authors.forename: Aedin
authors.initials: A
authors.lastname: Cassidy
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging and.
authors.forename: Gail
authors.initials: G
authors.lastname: Rogers
authors.affiliation: The Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA;
authors.forename: Julia J
authors.initials: JJ
authors.lastname: Peterson
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging and The Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA; Tufts University School of Medicine and Frances Stern Nutrition Center, Tufts Medical Center, Boston, MA; and.
authors.forename: Johanna T
authors.initials: JT
authors.lastname: Dwyer
authors.affiliation: Section of Computational Biomedicine, Department of Medicine, Boston University School of Medicine, Boston, MA.
authors.forename: Honghuang
authors.initials: H
authors.lastname: Lin
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging and The Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA; paul.jacques@tufts.edu.
authors.forename: Paul F
authors.identifier: http://orcid.org/0000-0001-5567-3147
authors.initials: PF
authors.lastname: Jacques
mesh_terms: D000872:Anthocyanins / Q000008:administration & dosage*; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage*; D001205:Ascorbic Acid / Q000008:administration & dosage; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D004032:Diet; D004305:Dose-Response Relationship, Drug; D002149:Energy Intake; D005260:Female; D044950:Flavanones / Q000008:administration & dosage; D047309:Flavones; D044948:Flavonols / Q000008:administration & dosage*; D005638:Fruit; D006801:Humans; D007249:Inflammation / Q000453:epidemiology*; D016014:Linear Models; D008297:Male; D027845:Malus; D008875:Middle Aged; D009043:Motor Activity; D015999:Multivariate Analysis; D064887:Observational Studies as Topic; D017419:Potassium, Dietary / Q000008:administration & dosage; D031989:Pyrus; D011795:Surveys and Questionnaires; D014481:United States / Q000453:epidemiology
chemical_list: D000872:Anthocyanins; D000893:Anti-Inflammatory Agents; D044950:Flavanones; D047309:Flavones; D044948:Flavonols; D017419:Potassium, Dietary; D001205:Ascorbic Acid
keywords: anthocyanins; dietary intake; flavonoids; flavonols; inflammation