Flaxseed in Preventing Breast Cancer in Premenopausal Women at Risk of Developing Breast Cancer

* Patients enrolled in must meet ≥ 1 of the following criteria: * History of unilateral or bilateral atypical ductal hyperplasia with or without family history * History of atypical lobular hyperplasia or lobular carcinoma in situ with or without family history * History of ductal carcinoma in situ * Prior stage I breast cancer allowed provided it was adequately treated and therapy was completed ≥ 1 year ago * Lifetime risk for developing breast cancer \> 20% (based on Gail or Claus model) * No abnormal mammogram requiring short-term follow-up within the past 6 months * No severe atypia or carcinoma cells on RPRNA PATIENT CHARACTERISTICS: * Premenopausal * ECOG performance status 0-1 * Patients enrolled must meet the following criteria: * No peri- or postmenopausal status as determined by estradiol levels \< 20 ng/dL and FSH levels \> 45 ng/dL * No thrombocytopenia (defined as platelet count \< 50,000/mm\^3) * Creatinine ≤ 1.5 mg/dL * Not pregnant or nursing * Fertile patients must use effective contraception consistently * No other prior malignancy allowed except for the following: * Basal cell or squamous cell carcinoma * In situ cervical cancer * No history of any of the following conditions within the past 5 years: * Crohn disease * Ulcerative colitis * Inflammatory bowel disease * Irritable bowel syndrome * Celiac sprue * Malabsorption syndrome * Diverticulitis * Diverticulosis * No allergy to fl…