Dietary B-Vitamin Intake and Risk of Breast, Endometrial, Ovarian and Colorectal Cancer among Canadians

Nutr Cancer. 2019;71(7):1067-1077. doi: 10.1080/01635581.2019.1597904. Epub 2019 Apr 7.


Few studies have explored the associations of thiamin, niacin and riboflavin with risk of cancer despite their role in potentially cancer-associated one-carbon metabolism. Using multivariable Cox proportional hazards regression models modified for the case-cohort design, we examined the associations of dietary intake of the above-mentioned B vitamins, as well as folate, and vitamins B6 and B12, with risk of the breast (n = 922), endometrial (n = 180), ovarian (n = 104) and colorectal (n = 266) cancers among age-stratified subcohorts of 3,185 women who were randomly selected from a cohort of 73,909 participants. None of the B-vitamins were associated with risk of breast or colorectal cancers. However, relatively high dietary intake of folate intake was inversely associated with risk of endometrial (HRq4 vs q1: 0.52; 95% CI: 0.29-0.93) and ovarian (HRq3 vs q1: 0.39; 95% CI: 0.19-0.80) cancers while relatively high dietary intake of vitamin B6 was inversely associated with ovarian cancer risk (HRq3 vs q1: 0.49; 95% CI: 0.24-0.98). These findings suggest that dietary intake of folate may reduce risk of endometrial and ovarian cancers and dietary intake of vitamin B6 may reduce risk of ovarian cancer.

MeSH terms

  • Breast Neoplasms / epidemiology
  • Breast Neoplasms / prevention & control*
  • Canada / epidemiology
  • Cohort Studies
  • Colorectal Neoplasms / epidemiology
  • Colorectal Neoplasms / prevention & control*
  • Dietary Supplements
  • Endometrial Neoplasms / epidemiology
  • Endometrial Neoplasms / prevention & control*
  • Female
  • Folic Acid / pharmacology
  • Humans
  • Male
  • Micronutrients / pharmacology
  • Ovarian Neoplasms / epidemiology
  • Ovarian Neoplasms / prevention & control*
  • Proportional Hazards Models
  • Risk Factors
  • Vitamin B Complex / pharmacology*


  • Micronutrients
  • Vitamin B Complex
  • Folic Acid