Lifestyle Interventions in Patients in Active Surveillance for Prostate Cancer: A Systematic Review

Background/Objectives: Active surveillance (AS) has become the gold standard for managing men diagnosed with low-risk or favorable intermediate-risk prostate cancer. However, both patients and healthcare providers often face a lack of clear, evidence-based guidance regarding lifestyle choices during this period. This systematic review was designed to determine whether specific lifestyle modifications-including dietary changes, physical activity, weight control, and use of supplements-can tangibly impact oncologic outcomes or improve patient-reported quality of life during surveillance. Methods: The research followed PRISMA protocols, searching PubMed, Cochrane, and Scopus for studies published between 2000 and 2025. The team included diverse methodologies, from randomized controlled trials to qualitative interviews, specifically focusing on men on AS. To ensure high standards, two independent reviewers performed data extraction and quality assessments using CASP tools, and the review was formally registered with PROSPERO. Results: The review synthesized data from over 30 heterogeneous studies. The findings suggest that lifestyle interventions are safe and highly feasible. Physical exercise emerged as the most effective intervention, consistently improving cardiorespiratory fitness and reducing psychological burdens such as fatigue and "PSA anxiety." While dietary changes and weight loss successfully improved metabolic health markers, they did not show a consistent ability to prevent biopsy upgrading or MRI progression. Similarly, supplements showed only minor, short-term effects on PSA kinetics without providing reproducible oncologic protection. Conclusions: For men undergoing active surveillance, lifestyle interventions may be considered as supportive measures, as they appear feasible and may improve physical fitness, metabolic health, and selected patient-reported outcomes. However, current evidence remains insufficient to demonstrate a consistent effect on biopsy upgrading, MRI progression, or long-term deferral of definitive treatment.