Effects of sugar and confectionery consumption on serum testosterone levels in males: a narrative review

The global rise in consumption of added sugars and confectionery parallels the increasing prevalence of obesity, metabolic dysfunction, and male hypogonadism. Testosterone is essential for male reproductive, metabolic, and cardiovascular health, and growing evidence indicates that excessive sugar intake may disrupt hormonal regulation. This narrative review synthesizes data from human observational and interventional studies and experimental animal models to evaluate the effects of sugar consumption on testosterone homeostasis and male reproductive outcomes. Acute glucose ingestion is associated with hyperinsulinemia and inflammatory cytokine release, which may contribute to transient reductions in circulating testosterone of approximately 20–30%, although findings vary across populations and study designs. Chronic high-sugar intake, particularly from sugar-sweetened beverages, promotes oxidative stress, adiposity, insulin resistance, and leptin dysregulation, which may collectively impair Leydig cell steroidogenesis and contribute to testosterone suppression. Animal studies consistently demonstrate testicular structural damage, downregulation of steroidogenic enzymes, and impaired spermatogenesis under high-sugar dietary conditions. Epidemiological studies associate frequent intake of sugar-sweetened beverages and confectionery with lower testosterone levels and poorer semen parameters. Emerging evidence suggests partial reversibility with dietary interventions emphasizing reduced sugar intake and increased antioxidant consumption. Overall, current data support a biologically plausible link between excessive sugar intake and impaired testosterone regulation, underscoring the need for longitudinal studies and public health strategies targeting added sugar reduction.