This review critically analyses the transforming terrain of sensor-based IoT-enabled healthcare systems and their connected aspects with an eye toward the complex interaction between components, the fusion of IoT and healthcare, and the vital junction between artificial intelligence (AI) and security. By means of analysis of the components of wearable devices, medical instruments, data transmission techniques, cloud platforms, and user interfaces in sensor-based healthcare systems, we may better understand their combined relevance in supporting real-time health monitoring and customized therapies. Investigating IoT integration into healthcare emphasizes the perfect device connectivity and consequent continuous data streams that enable patients and enhance healthcare services. Emphasizing the critical relevance of security in IoT applications for healthcare, the review provides an in-depth study of encryption mechanisms, authentication protocols, access restrictions, device integrity checks, and safe communication protocols, stressing their indispensable role in preserving the confidentiality and integrity of private health data. Furthermore, the study focuses on how artificial intelligence impacts healthcare results by isolating its contributions in customized medicine, predictive modelling, and data analytics. A thorough examination of the existing status and problems, considering future paths of sensor-based IoT-enabled healthcare systems, contributes to a fundamental grasp of the complex interplay between sensors, IoT, artificial intelligence, and security, thus directing the creation of intelligent and safe healthcare ecosystems.