Specialty Supplements and Breast Cancer Risk in the VITamins And Lifestyle (VITAL)Cohort Theodore M.Brasky 1,2 ,Johanna W.Lampe 1,2 ,John D.Potter 1,2 ,Ruth E.Patterson 3 ,and Emily White 1,2
Abstract Background:Use of nonvitamin,nonmineral “specialty”supplements has increased substantially over recent decades.Several supplements may have anti-inflammatory or anticancer properties.Additionally, supplements taken for symptoms of menopause have been associated with reduced risk of breast cancer in two case-control studies.However,there have been no prospective studies of the association between the long-term use of these supplements and breast cancer risk . Methods:Participants were female members of the VITamins And Lifestyle (VITAL)Cohort.Postmeno-pausal women,ages 50 to 76 years,who were residents of western Washington State,completed a 24-page baseline questionnaire in 2000 to 2002 (n =35,016).Participants were queried on their recency (current versus past),frequency (days/week),and duration (years)of specialty supplement use.Incident invasive breast cancers (n =880)from 2000 to 2007 were obtained from the Surveillance, Epidemiology, and End Results registry. Multivariable-adjusted hazards ratios (HR)and 95%confidence intervals (95%CI)were estimated by Cox proportional hazards models. Results:Current use of fish oil was associated with reduced risk of breast cancer HR,0.68;95%CI,0.50- 0.92).Ten-year average use was suggestive of reduced risk (P trend =0.09).These results held for ductal but not lobular cancers.The remaining specialty supplements were not associated with breast cancer risk: Specifically,use of supplements sometimes taken for menopausal symptoms (black cohosh,dong quai,soy, or St.John’s wort) was not associated with risk.
Conclusions:Fish oil may be inversely associated with breast cancer risk. Impact:Fish oil is a potential candidate for chemoprevention studies. Until that time,it is not recommended for individual use for breast cancer prevention. Cancer Epidemiol Biomarkers Prev;19(7);1696–708.