ARTICLE

Breast cancer is the most common cancer among women ( 1). Many risk factors for the development of breast cancer have been identi-fied, including older age, early menarche, late menopause, nullipar-ity, higher breast density, atypical hyperplasia, family history of breast cancer, and mutation of the BRCA1 or BRCA2 genes ( 1). Many of these risk factors are not modifiable. However, lifestyle, behavioral, or dietary approaches to prevention of breast cancer, including a low-fat diet ( 2, 3), exercise ( 4, 5), and reduction in alco-hol consumption ( 6), may hold some promise. Chemoprevention with antiestrogens also appears to be effec-tive in reducing risk of breast cancer. In a large placebo-controlled trial conducted by National Surgical Adjuvant Breast and Bowel Project in North America (NSABP P-1), treatment with tamoxifen reduced the incidence of invasive breast cancer by 49 % ( 7). However, use of tamoxifen has been associated with increased ris