title: Intake of Vitamin and Mineral Supplements and Longitudinal Association with HbA1c Levels in the General Non-Diabetic Population--Results from the MONICA/KORA S3/F3 Study.
abstract: BACKGROUND
  Lower levels of hemoglobin A1c (HbA1c) are associated with a decreased risk of cardiovascular complications in diabetic and non-diabetic individuals. The aim of the study was to longitudinally investigate the association between the use of 11 vitamins and minerals (vitamins E, C, D, B1, folic acid, carotenoids, calcium, magnesium, zinc, iron, and selenium) and change in HbA1c levels over 10 years in non-diabetic individuals drawn from the general population.
  
  
  METHODS
  Baseline data were available from 4447 subjects included in the population-based "Monitoring of Trends and Determinants in Cardiovascular Diseases" (MONICA) Augsburg S3 survey (1994/95). Follow-up data were derived from 2774 participants in the follow-up survey named "Cooperative Health Research in the Region of Augsburg" (KORA) F3 (2004/05). Vitamin/mineral intake from supplements and medications was assessed in a personal interview, where participants were asked to bring product packages of preparations that had been ingested during the last 7 days prior to the examination. Associations between regular vitamin/mineral intake amounts and HbA1c levels measured at baseline and follow-up were investigated using generalized estimating equation models. For carotenoids, analyses were stratified by smoking status.
  
  
  RESULTS
  None of the investigated nutrients except for carotenoids was significantly associated with changes in HbA1c levels after 10 years. Regular intake of carotenoids from supplements and medications in amounts > 6.8 mg/d (upper tertile) was associated with an absolute -0.26% (95% CI: -0.43 to -0.08) lower increase in HbA1c levels compared with no intake of carotenoids. An inverse association was observed in those who never smoked but not in (former) smokers.
  
  
  CONCLUSIONS
  Larger prospective and intervention studies in non-diabetic/non-smoking individuals are needed to confirm the results and to assess whether the observed associations between carotenoid intake and change in HbA1c levels are causal. If our results are confirmed, high carotenoid intake could be one strategy for the prevention of cardiovascular complications in non-diabetic people.
authors.affiliation: Institute of Epidemiology II, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany.
authors.forename: Sigrid
authors.initials: S
authors.lastname: Schwab
authors.affiliation: Institute of Epidemiology II, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany.
authors.forename: Astrid
authors.initials: A
authors.lastname: Zierer
authors.affiliation: Institute of Epidemiology II, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; MONICA/KORA Myocardial Infarction Registry, Central Hospital of Augsburg, Augsburg, Germany.
authors.forename: Margit
authors.initials: M
authors.lastname: Heier
authors.affiliation: Department of Epidemiology and Preventive Medicine, University of Regensburg, Regensburg, Germany.
authors.forename: Beate
authors.initials: B
authors.lastname: Fischer
authors.affiliation: Institute of Epidemiology II, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; German Center for Diabetes Research (DZD e.V.), Neuherberg, Germany.
authors.forename: Cornelia
authors.initials: C
authors.lastname: Huth
authors.affiliation: Institute of Epidemiology II, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; German Center for Diabetes Research (DZD e.V.), Neuherberg, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Baumert
authors.affiliation: Institute of Epidemiology II, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; MONICA/KORA Myocardial Infarction Registry, Central Hospital of Augsburg, Augsburg, Germany.
authors.forename: Christa
authors.initials: C
authors.lastname: Meisinger
authors.affiliation: Institute of Epidemiology II, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; German Center for Diabetes Research (DZD e.V.), Neuherberg, Germany.
authors.forename: Annette
authors.initials: A
authors.lastname: Peters
authors.affiliation: Institute of Epidemiology II, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; German Center for Diabetes Research (DZD e.V.), Neuherberg, Germany.
authors.forename: Barbara
authors.initials: B
authors.lastname: Thorand
mesh_terms: D000328:Adult; D000368:Aged; D019587:Dietary Supplements; D005260:Female; D005500:Follow-Up Studies; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006801:Humans; D008297:Male; D008670:Metals / Q000008:administration & dosage*; D008875:Middle Aged; D008954:Models, Biological; D014815:Vitamins / Q000008:administration & dosage*
chemical_list: D006442:Glycated Hemoglobin; D008670:Metals; D014815:Vitamins; C517652:hemoglobin A1c protein, human