Circadian Rhythm (CR), which is the interchange between day and night, has a vital role in the health of all living creatures including plants. It is a biological process that echoes an internal clock in the body oscillating during the whole 24 hours of the day. Within that time, it fluctuates to control the sleep period that alternates with wakefulness at regular intervals. There is a complex interaction between sleep and all parts of the human body. A good night's sleep influences CR and is essential for the body organs and cells' efficient physiological function. Industrial development, modernization, and many other illnesses are all causes for the disturbance of the CR. Such disruption may lead to several dangerous health problems like; cerebral problems, cardiovascular diseases, pulmonary embolism, metabolic syndromes, infections, gastrointestinal issues, menstrual irregularities, mental disorders, and psychiatric illnesses. Besides, CR disruption has a carcinogenic effect on various organs. In this review, we highlight the functional importance of CR and the health consequences of its disruption.