Flaxseed, a phytoestrogen, is a natural food supplement rich in plant ligands, which have a very weak estrogen effect. In this study, flaxseed is being evaluated in regard to its capacity to safely and effectively treat hot flashes. Specifically, this study seeks to determine if flaxseed will lower the number and severity of hot flashes and if women experience any side effects from taking flaxseed for this purpose.

Inclusionary Criteria:

• Age greater than or equal to 18 years
• Women with a history of breast cancer (currently without malignant disease) or women who have no history of breast cancer but who wish to avoid estrogen due to a perceived increased risk of breast cancer.
• Bothersome hot flashes (defined by occurenece of greater than or equal to 14 times per week and of sufficient severity to make the patient desire therapeutic intervention).
• Presence of hot flashes for greater than or equal to 1 month prior to study entry.
• Life expectancy greater than or equal to 6 months.
• ECOG Performance Status (PS) 0 or 1 (see Appendix VIII)

Exclusionary Criteria/Contraindications

• Any of the following current (less than or equal to 4 weeks) or planned therapies (tamoxifen, raloxifene, or aromatase inhibitors are allowed, but patient must have been on a constant dose for greater than or equal to 4 weeks and must not be expected to stop the medication during the study period): antineoplastic chemotherapy, androgens, estrogens, progestational agents, other herbal supplements, including soy (herbal teas from a grocery store are allowed), warfarin (1 mg of daily warfarin is allowed for central line patency)
• History of allergic or other adverse reaction to flaxseed, wheat, nuts, lactose, and/or certain spices
• Current or planned use of other agents for treating hot flashes (except stable dose of vitamine E or antidepressants are allowed as long as they wre started >30 days prior to study initiation and are to be continued through the study period).
• Diabetes (as flaxseed can lower blood glucose levels and might have additive effects when used with antidiabetic drugs).
• Diagnosis of/problems with chronic diarrhea or history of bowel obstruction or esophageal stricture.
• Any of the following: pregnant women, nursing women, women of childbearing potential who are unwilling to employ adequate contraception
• Current use of anticoagulants including aspirin, clopidogrel (Plavix), ticlopidine (Ticlic), and coumadin (1 mg of dialy coumadin is allowed for central line patency).
• Diagnosis of/problems with von Willebrand's disease or other bleeding disorders.