title: Antioxidant vitamins and coronary heart disease risk: a pooled analysis of 9 cohorts.
abstract: BACKGROUND
  Epidemiologic studies have suggested a lower risk of coronary heart disease (CHD) at higher intakes of fruit, vegetables, and whole grain. Whether this association is due to antioxidant vitamins or some other factors remains unclear.
  
  
  OBJECTIVE
  We studied the relation between the intake of antioxidant vitamins and CHD risk.
  
  
  METHODS
  A cohort study pooling 9 prospective studies that included information on intakes of vitamin E, carotenoids, and vitamin C and that met specific criteria was carried out. During a 10-y follow-up, 4647 major incident CHD events occurred in 293 172 subjects who were free of CHD at baseline.
  
  
  RESULTS
  Dietary intake of antioxidant vitamins was only weakly related to a reduced CHD risk after adjustment for potential nondietary and dietary confounding factors. Compared with subjects in the lowest dietary intake quintiles for vitamins E and C, those in the highest intake quintiles had relative risks of CHD incidence of 0.84 (95% CI: 0.71, 1.00; P=0.17) and 1.23 (1.04, 1.45; P=0.07), respectively, and the relative risks for subjects in the highest intake quintiles for the various carotenoids varied from 0.90 to 0.99. Subjects with higher supplemental vitamin C intake had a lower CHD incidence. Compared with subjects who did not take supplemental vitamin C, those who took >700 mg supplemental vitamin C/d had a relative risk of CHD incidence of 0.75 (0.60, 0.93; P for trend <0.001). Supplemental vitamin E intake was not significantly related to reduced CHD risk.
  
  
  CONCLUSIONS
  The results suggest a reduced incidence of major CHD events at high supplemental vitamin C intakes. The risk reductions at high vitamin E or carotenoid intakes appear small.
authors.affiliation: National Public Health Institute, Helsinki, Finland. paul.knekt@ktl.fi
authors.forename: Paul
authors.initials: P
authors.lastname: Knekt
authors.forename: John
authors.initials: J
authors.lastname: Ritz
authors.forename: Mark A
authors.initials: MA
authors.lastname: Pereira
authors.forename: Eilis J
authors.initials: EJ
authors.lastname: O'Reilly
authors.forename: Katarina
authors.initials: K
authors.lastname: Augustsson
authors.forename: Gary E
authors.initials: GE
authors.lastname: Fraser
authors.forename: Uri
authors.initials: U
authors.lastname: Goldbourt
authors.forename: Berit L
authors.initials: BL
authors.lastname: Heitmann
authors.forename: Göran
authors.initials: G
authors.lastname: Hallmans
authors.forename: Simin
authors.initials: S
authors.lastname: Liu
authors.forename: Pirjo
authors.initials: P
authors.lastname: Pietinen
authors.forename: Donna
authors.initials: D
authors.lastname: Spiegelman
authors.forename: June
authors.initials: J
authors.lastname: Stevens
authors.forename: Jarmo
authors.initials: J
authors.lastname: Virtamo
authors.forename: Walter C
authors.initials: WC
authors.lastname: Willett
authors.forename: Eric B
authors.initials: EB
authors.lastname: Rimm
authors.forename: Alberto
authors.initials: A
authors.lastname: Ascherio
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000975:Antioxidants / Q000008:administration & dosage* / Q000494:pharmacology; D001205:Ascorbic Acid / Q000008:administration & dosage* / Q000494:pharmacology; D002338:Carotenoids / Q000008:administration & dosage* / Q000494:pharmacology; D015331:Cohort Studies; D003327:Coronary Disease / Q000453:epidemiology* / Q000401:mortality; D004034:Diet Surveys; D019587:Dietary Supplements; D005260:Female; D005500:Follow-Up Studies; D005638:Fruit; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012306:Risk; D012307:Risk Factors; D014675:Vegetables; D014810:Vitamin E / Q000008:administration & dosage* / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D014810:Vitamin E; D002338:Carotenoids; D001205:Ascorbic Acid