Vitamin D and prevention of breast cancer: pooled analysis

J Steroid Biochem Mol Biol. 2007 Mar;103(3-5):708-11. doi: 10.1016/j.jsbmb.2006.12.007.

Abstract

Background: Inadequate photosynthesis or oral intake of Vitamin D are associated with high incidence and mortality rates of breast cancer in ecological and observational studies, but the dose-response relationship in individuals has not been adequately studied.

Methods: A literature search for all studies that reported risk by of breast cancer by quantiles of 25(OH)D identified two studies with 1760 individuals. Data were pooled to assess the dose-response association between serum 25(OH)D and risk of breast cancer.

Results: The medians of the pooled quintiles of serum 25(OH)D were 6, 18, 29, 37 and 48 ng/ml. Pooled odds ratios for breast cancer from lowest to highest quintile, were 1.00, 0.90, 0.70, 0.70 and 0.50 (p trend<0.001). According to the pooled analysis, individuals with serum 25(OH)D of approximately 52 ng/ml had 50% lower risk of breast cancer than those with serum <13 ng/ml. This serum level corresponds to intake of 4000 IU/day. This exceeds the National Academy of Sciences upper limit of 2000 IU/day. A 25(OH)D level of 52 ng/ml could be maintained by intake of 2000 IU/day and, when appropriate, about 12 min/day in the sun, equivalent to oral intake of 3000 IU of Vitamin D(3).

Conclusions: Intake of 2000 IU/day of Vitamin D(3), and, when possible, very moderate exposure to sunlight, could raise serum 25(OH)D to 52 ng/ml, a level associated with reduction by 50% in incidence of breast cancer, according to observational studies.

MeSH terms

  • Administration, Oral
  • Breast Neoplasms / epidemiology*
  • Breast Neoplasms / pathology
  • Breast Neoplasms / prevention & control*
  • Humans
  • Risk Factors
  • Vitamin D / administration & dosage
  • Vitamin D / blood
  • Vitamin D / pharmacology*

Substances

  • Vitamin D