title: Micronutrient intake in relation to all-cause mortality in a prospective Danish cohort.
abstract: BACKGROUND
  Few studies have considered source-specific micronutrient intake in relation to mortality under the consideration that dietary and supplemental intake could exhibit different effects.
  
  
  OBJECTIVE
  To evaluate the association between intake of vitamin C, E, folate, beta-carotene from diet and supplements, and overall mortality. Furthermore, to examine effect modification by smoking, alcohol intake, and BMI and to investigate if the effect of supplement use differs with dietary micronutrient intake.
  
  
  METHODS
  In a prospective cohort study of 55,453 middle-aged Danes, information regarding diet, supplement use, and lifestyle was collected through questionnaires. During follow-up, 6,767 deaths were identified and incidence rate ratios (IRRs) of mortality related to micronutrient intake were calculated using Cox proportional hazards models.
  
  
  RESULTS
  The present study found no effect of dietary vitamin C, E, folate, or beta-carotene in relation to mortality. In contrast, supplemental folic acid was associated with a significantly increased mortality, whereas no other micronutrient supplement was associated with mortality. Effect modification by smoking and alcohol intake, but not BMI, was suggested in relation to some dietary micronutrients. The effect of supplements did not differ in groups defined by dietary micronutrient intake.
  
  
  CONCLUSIONS
  This study suggests no effect of dietary micronutrients in relation to overall mortality. Supplemental folic acid was found to be associated with increased mortality, but further studies are required. No other supplemental micronutrient was associated with mortality.
authors.affiliation: Institute of Cancer Epidemiology, Danish Cancer Society, Copenhagen, Denmark.
authors.forename: Nina
authors.initials: N
authors.lastname: Roswall
authors.forename: Anja
authors.initials: A
authors.lastname: Olsen
authors.forename: Jane
authors.initials: J
authors.lastname: Christensen
authors.forename: Louise
authors.initials: L
authors.lastname: Hansen
authors.forename: Lars O
authors.initials: LO
authors.lastname: Dragsted
authors.forename: Kim
authors.initials: K
authors.lastname: Overvad
authors.forename: Anne
authors.initials: A
authors.lastname: Tjønneland