CIRCADIAN RHYTHM DISRUPTION AND HORMONAL HEALTH: THE IMPACT OF MODERN LIFESTYLE

The circadian rhythm is one of the key homeostatic mechanisms of the human body, regulating hormone secretion, energy metabolism, and the sleep-wake cycle. The aim of this review was to present the current state of knowledge on the impact of circadian rhythm disorders on the functioning of the endocrine system and to assess the consequences of modern lifestyles on hormonal balance. A literature review was conducted in the PubMed, Scopus, Web of Science, and Google Scholar databases, covering publications from 2000 to 2025. Twenty-six peer-reviewed papers of high methodological quality were included, analyzing the relationship between circadian rhythm desynchronization and the regulation of hormonal axes. The collected data indicate that circadian rhythm disorders—resulting from exposure to artificial light, shift work, irregular sleep and meals—lead to desynchronization between the suprachiasmatic nucleus (SCN) and peripheral clocks. This leads to dysregulation of the HPA, HPG, and HPT axes. Loss of physiological pulsatility of cortisol and melatonin secretion, insulin resistance, hypercortisolemia, and fertility disorders are observed. Long-term adaptation to these disorders is incomplete, and persistent hormonal changes promote the development of metabolic and cardiovascular diseases. The conclusions emphasize the need for chronobiological prevention through controlling exposure to light, maintaining a regular sleep and meal schedule, and limiting shift work. Circadian rhythm disorders are a significant, though often underestimated, pathogenic factor in lifestyle diseases.