The 24/7 lifestyle and male hormonal health: how sleep deprivation and ultra-processed foods impact testosterone and reproduction

Sleep is a fundamental physiological state essential for the regulation of multiple biological systems, including hormonal homeostasis. However, in modern society, both the duration and quality of sleep have been progressively declining. Emerging evidence suggests that sleep deprivation (SD) leads to reduced testosterone levels, which may negatively affect male reproductive health. Concurrently, the excessive consumption of ultra-processed foods (UPF) represents another major global health concern. Beyond increasing the risk of cardiometabolic disorders, UPF intake has been linked to decreased testosterone concentrations. As the primary male sex hormone, testosterone plays a critical role in maintaining numerous physiological functions, and its deficiency has been associated with a number of negative impacts including systemic inflammation, insulin resistance, increased cortisol secretion, premature aging of testosterone-producing Leydig cells, blood-testis barrier (BTB) disruption, melatonin decrease, and diet-related transcriptional remodeling of testicular cell populations. These factors may underlie the reduction in serum testosterone levels observed in both individuals with SD and with high UPF consumption. Given that SD and UPF can independently decrease testosterone levels, their potential combined impact within the context of a modern 24/7 lifestyle requires greater attention. The association between insufficient sleep and poor dietary habits may have significant implications for male reproductive health, potentially contributing to infertility and disrupting normal physiological functions. This review draws attention to the complex interplay of lifestyle factors in shaping male hormonal health, emphasizing the importance of integrative perspectives. This narrative review discusses how the combined impact of SD and UPF consumption may exert convergent or additive effects on testosterone regulation, with broad implications for reproductive function and public health strategies.