Effects of White Button Mushroom on Inflammation in Obese Postmenopausal Women at High Risk of Breast Cancer

Inclusion Criteria: * This study will be conducted in postmenopausal women who have increased risk of breast cancer and high BMI \>= 30 kg/m\^2 * The study population will consist of women with a relative risk of developing breast cancer that is at least \> 2 x that of the general population for their age group based on any of the following: * Have a known genetic mutation associated with hereditary breast cancer (including BRCA1, BRCA2, p53, etc.) * One or more first degree relatives with breast cancer, with at least one under the age of 60 * Two or more second degree relatives with breast cancer, with at least one under the age of 50 * Prior biopsy diagnosing atypical lobular hyperplasia, atypical ductal hyperplasia, lobular carcinoma in situ, or ductal carcinoma in situ in the last 10 years * Have a Gail Risk Assessment (which is based on age, race, age of menarche, age of first live birth, number of first degree relatives with breast cancer, number of breast biopsies, and presence of high risk histology on any biopsies) that is considered high risk compared to the general population i.e. 5 year Gail \>= 1.7 * Prior diagnosis of T1 or T2 breast cancer \>= 5 years, without antiestrogen therapy for \> six months when applicable * ELIGIBILITY CRITERIA FOR HIGH RISK PATIENTS FOR THE CLINICAL TRIAL * Body mass index (BMI) \>= 30 (Asian BMI \>= 25 kg/m\^2) * Postmenopausal, defined as continuous absence of menstruation for 12+ months, status post bilateral oophorec…