Background: Neurodegenerative diseases (NDs), such as Alzheimer's disease, Parkinson's disease, and multiple sclerosis, represent a growing public health challenge worldwide. While genetic predisposition plays a critical role, lifestyle factors such as diet, physical activity, sleep patterns, and substance use have been increasingly recognized as key contributors to the onset and progression of NDs. Understanding the influence of these modifiable factors can inform preventive and therapeutic strategies. Materials and Methods: A cross-sectional study was conducted on 250 participants aged 40–75 years, including 150 individuals diagnosed with NDs and 100 healthy controls. Data on lifestyle factors were collected using validated questionnaires, dietary recalls, and activity logs. Cognitive and motor functions were assessed using standard neuropsychological tests. Statistical analysis involved logistic regression to identify associations between lifestyle factors and ND risk, and a multivariate analysis of variance (MANOVA) to evaluate group differences. Results: Participants with NDs demonstrated significantly lower adherence to a Mediterranean diet (mean adherence score: 5.2 ± 1.3) compared to controls (7.8 ± 1.1, p < 0.01). Regular physical activity was associated with a 35% reduced risk of NDs (OR: 0.65, 95% CI: 0.50–0.85, p < 0.05). Sleep disturbances were prevalent in 70% of ND cases compared to 30% in controls (p < 0.01). Smoking and excessive alcohol consumption were strongly correlated with disease progression (r = 0.42, p < 0.001). Conclusion: This study highlights the significant influence of modifiable lifestyle factors on the development and progression of NDs. Dietary improvements, regular physical activity, and addressing sleep disturbances may serve as effective interventions to mitigate ND risk. Further longitudinal studies are needed to confirm these associations and guide public health initiatives.