title: Colon cancer in Chile before and after the start of the flour fortification program with folic acid.
abstract: BACKGROUND
  Folate depletion is associated with an increased risk of colorectal carcinogenesis. A temporal association between folic acid fortification of enriched cereal grains and an increase in the incidence of colorectal cancer in the USA and Canada has, however, been recently reported.
  
  
  OBJECTIVE
  To compare the rates of hospital discharges owing to colon cancer in Chile before and after the start of the mandatory flour fortification program with 220 microg of synthetic folic acid/100 g of wheat flour.
  
  
  METHODS
  Cancer and cardiovascular hospital discharge rates were compared using rate ratios between two study periods, 1992-1996, before folic acid fortification and 2001-2004, after the flour fortification with folic acid was established in the country. Standard errors of the log rate ratio to derive confidence intervals, and to test the null hypothesis of no difference, were calculated.
  
  
  RESULTS
  The highest rate ratio between the two periods was for colon cancer in the group aged 45-64 years (rate ratio: 2.6, confidence interval: 99% 2.93-2.58) and in the 65-79 years (rate ratio: 2.9, confidence interval: 99% 3.25-2.86).
  
  
  CONCLUSIONS
  Our data provide new evidence that a folate fortification program could be associated with an additional risk of colon cancer.
authors.affiliation: Aging and chronic diseases program, INTA, University of Chile, Santiago, Chile.
authors.forename: Sandra
authors.initials: S
authors.lastname: Hirsch
authors.forename: Hugo
authors.initials: H
authors.lastname: Sanchez
authors.forename: Cecilia
authors.initials: C
authors.lastname: Albala
authors.forename: María Pía
authors.initials: MP
authors.lastname: de la Maza
authors.forename: Gladys
authors.initials: G
authors.lastname: Barrera
authors.forename: Laura
authors.initials: L
authors.lastname: Leiva
authors.forename: Daniel
authors.initials: D
authors.lastname: Bunout
mesh_terms: D000368:Aged; D002318:Cardiovascular Diseases / Q000453:epidemiology; D002677:Chile / Q000453:epidemiology; D003110:Colonic Neoplasms / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D005433:Flour; D005492:Folic Acid / Q000008:administration & dosage / Q000009:adverse effects*; D005527:Food, Fortified / Q000009:adverse effects*; D006801:Humans; D008875:Middle Aged; D009369:Neoplasms / Q000453:epidemiology; D010351:Patient Discharge / Q000706:statistics & numerical data
chemical_list: D005492:Folic Acid