Diabetes mellitus is a major global health issue, with rising prevalence and complications such as diabetic retinopathy (DR). Effective prevention strategies, including glycemic, lipid, and blood pressure control, are essential. Lifestyle interventions - particularly diet and physical activity - are increasingly recognized for their role in mitigating DR progression. The review followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and searched PUBMED, Web of Science, Cochrane Library, and ScienceDirect for studies published between 2010 and 2024. Included studies assessed the impact of dietary changes and physical activity on DR severity, retinal vascular complications, glycemic control (HbA1c), visual acuity, and inflammatory biomarkers. Statistical analysis, including risk ratios and heterogeneity, was performed using RevMan version 5.4.1 (The Cochrane Collaboration, Oxford, UK), and the risk of bias in randomized controlled trials (RCTs) was assessed accordingly. Across 10 studies involving various lifestyle interventions, combined diet and exercise significantly improved glycemic control (lower HbA1c), lipid profiles, inflammation markers, and slowed DR progression. Interventions such as culturally tailored education, e-coaching, and long-term physical activity were particularly effective. Sleep and gut microbiota also emerged as influential lifestyle factors. However, a few studies showed no significant long-term impact, highlighting the dominant role of cumulative HbA1c. HbA1c levels were reduced by up to 1.1% (e.g., from 7.2% to 6.1%, p <
0.05), and the progression rate of DR was reduced by 47% in long-term follow-up studies (HR = 0.53, 95% CI: 0.29-0.99). Lifestyle interventions - especially those combining a healthy diet and physical activity - effectively reduce DR progression in patients with diabetes by improving metabolic control and reducing inflammation. These findings support the integration of personalized, technology-assisted lifestyle programs into diabetes care for DR prevention. However, long-term glycemic control remains a critical factor.