Statement: children and illiterate adults are not able to take part in the primary trial.
Primary_evidence: Inclusion Criteria:   Age  18 and  85 years   Postmenopausal status defined as: no menstrual cycle in the past 12 months hysterectomy with bilateral oophorectomy hysterectomy with intact ovaries if age > 55 years   Newly diagnosed with incident, primary, invasive, estrogen receptor positive clinical stage II or lower breast cancer   ECOG performance status of 1 or less   Willingness to comply with study guidelines and procedures   Willingness and ability to provide informed consent   Usual consumption of soy no more than 1 time per week and willingness to avoid whole soy foods or concentrated soy sources (soy milk, tofu, substitute meat products, meal replacement bars) during the intervention period   Willingness to avoid herbal and dietary supplements (not including vitamins), aspirin, and ibuprofen during the intervention period   No competing neoadjuvant or chemotherapy treatment   Time between pre-surgical visit and surgery must be at least 2 weeks   No chemotherapy in the past 12 months Exclusion Criteria:   Inability to read and write English   Previous invasive breast cancer   Insulin dependent Type I or II diabetes diagnosed by physician   History of coagulopathy, thrombocytopenia, or bleeding disorder   Current (past 30 days) regular (at least once per week) use of reproductive hormone therapy, Tamoxifen, aromatase inhibitors, or other estrogen inhibitors, flaxseed, or antibiotics   Current chemotherapy or neoadjuvant chemotherapy   Allergies to flaxseed, nuts, or other seeds   Renal dysfunction defined as creatinine > 1.5 mg/dl   History of Crohns' disease, ulcerative colitis, irritable bowel syndrome, celiac sprue, or other malabsorption syndrome, diverticulitis, diverticulosis, or other bowel diagnosis which, in the opinion of the breast surgeon, would contraindicate large doses of dietary fiber or would impair nutrient absorption   Current, regular (more than once weekly) use of prescription blood-thinning agents including coumadin, heparin and heparin related drugs, clopidogrel bisulfate