Natural Strategies to Improve Sleep: The Role of the Circadian Rhythm

Sleep is essential for physical and mental health. However, modern lifestyles often disrupt the circadian rhythm, contributing to poor sleep quality and increasing the prevalence of sleep disorders. Prolonged circadian disruption has also been associated with adverse cardiovascular, metabolic, inflammatory, immune, and cognitive health outcomes, highlighting the importance of preserving healthy sleep patterns. This review examines the role of the circadian rhythm in sleep regulation and the biological mechanisms underlying its relationship with melatonin secretion. It also discusses how environmental cues and daily behaviors-including daytime and nighttime light exposure, screen use, bedroom temperature, sleep environment, sleep timing, and meal timing-may influence circadian alignment and healthy sleep. Because many of these factors are modifiable through simple, inexpensive, and accessible behavioral and environmental measures, they may represent practical complementary approaches to supporting healthy sleep. Understanding the relationship between circadian rhythm, melatonin, environmental cues, and daily habits may help individuals make informed choices that support restorative sleep and overall health.