Background: Chronic diseases, including cardiovascular diseases, diabetes, and cancer, have been significantly influenced by lifestyle factors such as diet, physical activity, smoking, and alcohol consumption. The early detection of cancer plays a crucial role in improving survival rates, and advancements in screening techniques have enhanced diagnostic accuracy. This study explores the impact of lifestyle factors on chronic diseases and evaluates the effectiveness of early detection methods for cancer, along with an overview of current cancer treatment strategies. Materials and Methods: A cross-sectional study was conducted on 500 individuals aged 30–70 years, including both healthy participants and those diagnosed with chronic diseases. Data were collected through structured questionnaires assessing lifestyle behaviors, medical history, and dietary patterns. Additionally, the study analyzed the effectiveness of early detection methods such as imaging techniques, biomarker analysis, and genetic screening. Statistical analysis was performed using SPSS software, with a significance level set at p < 0.05. Results: Among the participants, 65% reported unhealthy dietary habits, 40% were physically inactive, and 30% had a smoking history. A significant correlation was observed between lifestyle factors and chronic diseases (p = 0.001). Early detection methods showed a 90% sensitivity rate for identifying cancerous lesions, with biomarker analysis demonstrating higher accuracy (92%) compared to conventional imaging (85%). Cancer treatment strategies, including immunotherapy and targeted therapy, improved patient outcomes, with a 70% reduction in tumor progression observed in clinical trials. Conclusion: Unhealthy lifestyle habits significantly contribute to the prevalence of chronic diseases, including cancer. Early detection methods, particularly biomarker-based diagnostics, enhance the accuracy of cancer screening and improve treatment outcomes. Public health initiatives promoting healthier lifestyles and advancements in early cancer detection could reduce disease burden and improve overall health.