High Physical Activity During a Weight Loss Intervention for Breast Cancer Survivors and High Risk Women

Inclusion Criteria:

* Diagnosis of breast cancer having completed any cytotoxic chemotherapy, radiation or surgery at least 3 months prior to study entry (Cohort A2) OR No prior diagnosis of breast cancer but at high risk for development of breast cancer and participating in HSC 4601 (Cohort B)
* Body Mass Index (BMI) \>30 kg/m2. Women with a BMI \> 45 kg/m2 must be age \< 60 and ability to perform physical activity must be confirmed
* By self-assessment, currently performing 60 minutes or less of purposeful exercise per week but able to walk at least 30 minutes on a level surface
* Possession of smart phone capable of running MyFitnessPal and Garmin Connect apps and willing to have diet and exercise data accessed by study personnel
* Access to a personal computer
* Live in the greater Kansas City Metropolitan Area
* Willing and able to perform moderate intensity exercise at least 5 days per week for 6 months. This consists of a supervised exercise intervention at one of the 15 YMCAs affiliated with our program for 2 days per week. Must be willing to perform unsupervised home exercise for the entire 6 months.
* Willing to participate in a weekly behavioral modification group phone call for first 3 months and every 2 weeks for the second 3 months
* Willing to participate in a controlled dietary intervention with portion controlled meals and partial meal replacements plus 35 servings of fruits and vegetables/week for 6 months and track food intake and exercise
* Blood tests (Cohort A2) must have been performed after completion of any breast cancer surgery, radiation therapy, or cytotoxic chemotherapy, with reasonably normal liver and renal function as well as a hemoglobin of 10 or higher and/or performed within a year of study entry

Exclusion Criteria:

* Use of metformin, insulin, steroids or prescription weight loss or anti-psychotic drugs within the prior 3 weeks
* Individuals with prior gastric bypass surgery or procedure that would impair absorption of nutrients
* Need for chronic immunosuppressive drugs
* Participation within the past 6 months on a structured weight loss program such as Weight Watchers®
* Physical impairments (bad hip, knees, feet, peripheral neuropathy) that would prohibit performing moderate intensity exercise at least 5 days per week.
* Any other condition or intercurrent illness that in the opinion of the investigator makes the subject a poor candidate for participation in the trial such as recent cardiac event
* Currently receiving investigational agents in a clinical trial