SEATTLE—According to a new study at the Fred Hutchinson Cancer Research Center, fish oil may be inversely associated with breast cancer risk (Canc Epidemiol Biomark Prevent. July 19, 2010). Several supplements may have anti-inflammatory or anticancer properties. Many supplements that reduce menopausal symptoms are associated with a reduced risk of breast cancer according to two case-control studies. As a result, researchers conducted a study on the association between the long-term use of these supplements and breast cancer risk.
Participants were female members of the Vitamins and Lifestyle (VITAL) Cohort. Postmenopausal 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 timeliness (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.
Current use of fish oil was associated with reduced risk of breast cancer. An average use of 10 years was suggestive of a 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.
Duffy MacKay, N.D., vice president, scientific & regulatory affairs, Council for Responsible Nutrition (CRN), commented on the study’s finding, stating: “These results are exciting because this is a very large and well-done study published in a well-respected peer-reviewed publication. This study provides solid justification for additional intervention studies that use fish oil as a candidate for chemoprevention studies. There is mounting evidence that cancer is fueled (initiation and growth) by inflammatory processes in the body, and there is solid evidence that omega-3 status is directly related to the degree of systemic inflammation occurring in the body. It makes sense why the researchers would explore the link between fish oil intake and cancer.”
