Inclusion Criteria:

• Age ≥ 45 years OR post-menopausal AND cis-gender women at study registration.
• Overweight or World Health Organization (WHO) class 1 obese as defined by a body mass index (BMI) of 25 to 35 kg/m^2.
• High risk for breast cancer at the discretion of the physician, using standard definitions such as a Gail 5-year risk of ≥ 2% or Tyrer Cuzick version (v) 8.0 10-year risk of ≥ 5%.
• Concurrent or prior use of endocrine therapy is allowed. Any dose or schedule change is not permitted for the duration of the study.
• Currently established care or previously seen at the Ohio State University Comprehensive Cancer Center (OSUCCC) Stefanie Spielman Comprehensive Breast Center (SSCBC) high risk breast clinic.

Exclusion Criteria:

• Prior diagnosis of breast cancer within past 5 years.
• Metastatic breast cancer (at study start or during study period).
• BMI > 35 kg/m^2 or < 25 kg/m^2.
• Pre-menopausal women or < 45 years of age.
• Assigned male at birth.
• Uncontrolled intercurrent illness including lung disease, heart disease, metabolic disease; exacerbations for disease in past 8 weeks; unstable on medications for chronic conditions in past 6 weeks. This could affect compliance and engagement with study intervention. Change in anti-hyperglycemic or lipid lowering medications is best avoided for the duration of the study unless deemed necessary by treating provider or required for acute exacerbation of existing illness.
• Type 1 diabetes mellitus (DM) or insulin dependent, or evidence of brittle diabetes.
• Presence of food allergies or intolerances to wheat, nuts, seeds, fish, or dairy foods.
• Currently on special diet for known metabolic or gastrointestinal disease, or planning to start a specific dietary regimen such as vegetarian, vegan, ketogenic, low-fat diets, etc.
• Uncontrolled psychiatric illness/social situations that would limit compliance with study requirements.
• Unwilling or unable to follow protocol requirements.
• Pregnant, trying to get pregnant, or nursing.
• Any condition which in the investigator's opinion deems the subject an unsuitable candidate to participate in this study.
• Non-English speaking, as the teaching materials and educational sessions have not yet been translated into additional languages.
• Prisoners or other institutionalized patients.