DISEASE CHARACTERISTICS:

• Histologically confirmed adenocarcinoma (small cell acinar type) of the prostate

  • Has undergone an extended pattern biopsy (defined as 8+ cores) within the past 2 years OR is scheduled to undergo an extended pattern clinical biopsy within 6 weeks of starting study intervention and is willing to undergo 4 additional research core biopsies
  • No more than 33% of biopsy cores positive (> 33% of biopsy cores positive allowed if due to microfoci of adenocarcinoma)
  • No more than 50% of the length of a tumor core involved by carcinoma
• Clinical stage T1 or T2a disease
• Previously untreated disease
• Gleason score ≤ 6 with no pattern 4 or 5 histology (Gleason pattern 4 seen as a microfocus [< 2 mm in length] allowed)

• Prostate-specific antigen (PSA) ≤ 10.0 ng/mL (PSA < 15 ng/mL allowed for patients with benign prostatic hyperplasia or prostatitis)

  • Must have had 3 serum PSA levels performed ≥ 2 weeks apart over the past year to allow calculation of a PSA doubling time

    • No PSA doubling time of < 3 months
• Has chosen watchful waiting as treatment

PATIENT CHARACTERISTICS:

• ECOG performance status 0-2
• Life expectancy > 3 months
• Living in the greater San Francisco Bay Area
• Willing to make comprehensive lifestyle changes
• Baseline dietary fat intake ≥ 15%
• Able to participate in the exercise portion of this study, as determined by the cardiologist or primary care physician
• No limited exercise tolerance precluding participation in the lifestyle intervention component of this study
• No comprehensive lifestyle change similar to the lifestyle intervention used in this study

• No concurrent uncontrolled illness including, but not limited to, any of the following:

  • Ongoing or active infection
  • Symptomatic congestive heart failure
  • Unstable angina pectoris
  • Coronary artery disease requiring a revascularization procedure
  • Cardiac arrhythmia
  • Psychiatric illness/social situation that would limit compliance with study requirements

PRIOR CONCURRENT THERAPY:

• No prior or other concurrent treatment for prostate cancer, including any of the following:

  • Surgery
  • Radiotherapy
  • Hormonal therapy (e.g., leuprolide acetate, bicalutamide, flutamide, goserelin, megestrol acetate, nilutamide, or DES/estrogen)
  • Chemotherapy
  • PC-SPES
  • Investigational agents
• More than 4 weeks since prior and no concurrent finasteride or dutasteride
• More than 4 weeks since prior and no concurrent saw palmetto or any other herbal/nutritional preparation that would affect hormone levels
• More than 4 weeks since prior multivitamin/mineral and/or supplemental soy protein, vitamin E, vitamin C, selenium, fish oil, or any other preparation intended to supplement levels of omega-3 unsaturated fatty acids
• More than 1 month since prior and no concurrent NSAIDs, COX-2-inhibitors, and/or aspirin used for > 7 consecutive days