Back to 2015 Joint Annual Meeting

Introduction: Iron is essential to life but too much can be toxic. With few exceptions, iron comes exclusively from the diet. Genetic iron overload is associated with profound hypogonadotrophic hypogonadism, but little data are available on the associations of dietary iron intake with reproductive hormones and semen parameters in healthy men.
Materials & Methods: 189 healthy, 18-22 year old young men completed a validated 131-item food frequency questionnaire and provided blood and semen samples. Multivariable linear models adjusted for age, race, smoking status, BMI, abstinence time, and calorie, caffeine, alcohol and total fat intake.
Results: Dietary iron intake was positively associated with follicle stimulating hormone (FSH) (p=0.003) and inversely with inhibin B levels (p=0.025). Men in the highest quartile of iron intake (>24.3 mg/day) had 48% (95% CI 22-70%) higher FSH levels and 21% (95% CI 8-33%) lower inhibin B levels compared to those in the lowest intake quartile (<17.5 mg/day). No significant association was seen between iron intake and any semen parameter.
Conclusions: This study is the first to examine associations between dietary iron intake and markers of testicular function in healthy young men. Our data suggest that iron may negatively impact Sertoli cell function, as reflected by elevated FSH and decreased inhibin B levels, without affecting semen parameters. These data suggest that a moderate increase in iron may act at the level of the testis, as opposed to the pituitary impacts that are seen with severe iron overload.