title: Influence of quercetin supplementation on disease risk factors in community-dwelling adults.
abstract: BACKGROUND
  In vitro data indicate quercetin has antioxidative and anti-inflammatory functions with the potential to lower disease risk factors, but data in human beings are limited.
  
  
  OBJECTIVE
  The objective of this study was to investigate the effect of quercetin, vitamin C, and niacin supplements (500 mg quercetin, 125 mg vitamin C, and 5 mg niacin [Q-500]; 1,000 mg quercetin, 250 mg vitamin C, and 10 mg niacin [Q-1,000]), on disease risk factors in a large group of community adults (n=1,002, 60% women) varying widely in age and body mass index.
  
  
  METHODS
  Subjects were randomized into one of three groups (placebo, Q-500, or Q-1,000) and ingested supplements for 12 weeks. Blood samples were taken pre- and postsupplementation, and plasma quercetin, inflammatory markers (ie, C-reactive protein and five cytokines), diagnostic blood chemistries, blood pressure, and blood lipid profiles were measured.
  
  
  RESULTS
  Plasma quercetin increased in the Q-500 and Q-1,000 groups. No differences in blood chemistries were found except for a small decrease in serum creatinine and increase in glomerular filtration rate in Q-500 and Q-1,000 groups. A small decrease in mean arterial blood pressure was measured for Q-500 and Q-1,000 groups compared to placebo. A difference in serum total cholesterol was measured between Q-500 and placebo groups, and there was small decrease in high-density lipoprotein cholesterol levels in the Q-1,000 group. Change in inflammatory measures did not differ between groups except for a slight decrease in interleukin-6 for the Q-1,000 group.
  
  
  CONCLUSIONS
  Q-500 or Q-1,000 supplementation for 12 weeks had a negligible influence on disease risk factors.
authors: Appalachian State University, Kannapolis, NC, USA.
authors: Amy M
authors: AM
authors: Knab
authors: R Andrew
authors: RA
authors: Shanely
authors: Dru A
authors: DA
authors: Henson
authors: Fuxia
authors: F
authors: Jin
authors: Serena A
authors: SA
authors: Heinz
authors: Melanie D
authors: MD
authors: Austin
authors: David C
authors: DC
authors: Nieman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D000975:Antioxidants / Q000008:administration & dosage* / Q000378:metabolism; D001205:Ascorbic Acid / Q000008:administration & dosage / Q000097:blood; D001794:Blood Pressure / Q000187:drug effects; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism; D002318:Cardiovascular Diseases / Q000097:blood / Q000517:prevention & control*; D002908:Chronic Disease / Q000517:prevention & control; D016207:Cytokines / Q000097:blood; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D050356:Lipid Metabolism / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D009525:Niacin / Q000008:administration & dosage / Q000097:blood; D011794:Quercetin / Q000008:administration & dosage* / Q000097:blood*; D012307:Risk Factors; D055815:Young Adult
chemical_list: D000975:Antioxidants; D016207:Cytokines; D009525:Niacin; D002097:C-Reactive Protein; D011794:Quercetin; D001205:Ascorbic Acid