The New Night Watch: Advanced Sleep Sensors Uncover What Keeps Us Awake.

Sleep is fundamental to health and productivity, with insufficient rest linked to rising economic losses. Advances in wearables and non-contact sensors have transformed sleep monitoring from hospital-based polysomnography to everyday tracking via watches, rings, and beds. While consumer devices capture broad patterns, dedicated and FDA-cleared systems now approach clinical accuracy for disorders like sleep apnea. Embedded electronics and AI are driving the emergence of digital biomarkers, enabling personalized insights and long-term monitoring. This article reviews the evolution of sleep sensors, their convergence with clinical practice, and their growing role in preventive health.