Effect of ultra-processed food consumption on male reproductive and metabolic health

Consumption of ultra-processed food is associated with increased caloric intake and impaired health. Here, we conducted a nutrition trial (NCT05368194) with controlled, 2 × 2 crossover design and tested whether ultra-processed food impairs reproductive and metabolic fitness, with further aggravation by excess caloric intake. Comparing the response from an unprocessed to ultra-processed diet identified increased body weight and low-density lipoprotein (LDL):high-density lipoprotein (HDL) ratio, independent of caloric load. Several hormones involved in energy metabolism and spermatogenesis were affected, including decreased levels of growth/differentiation factor 15 and follicle-stimulating hormone. Sperm quality trended toward impairment, with a decrease in total motility. Differential accumulation of pollutants between the discordant diets were detected, such as decreased plasma lithium and a trend for increased levels of the phthalate mono(4-methyl-7-carboxyheptyl)phthalate (cxMINP) in serum, following the ultra-processed diet. Alteration in caloric load alone had distinct effects on the measured outcomes. This study provides evidence that consumption of ultra-processed food is detrimental for cardiometabolic and reproductive outcomes, regardless of excessive caloric intake.