Department of Nutritional Sciences, University of Toronto, Toronto, Canada.
Department of Urology, Murray Koffler Urologic Wellness Center, Mount Sinai Hospital, Toronto, Canada.
J Nutr. 2024 Sep;154(9):2680-2687. doi: 10.1016/j.tjnut.2024.06.013. Epub 2024 Jun 26.
Infertility impacts 16% of North American couples, with male factor infertility contributing to ∼30% of cases. Reproductive hormones, especially testosterone, are essential for spermatogenesis. An age-independent population-level decline in testosterone concentrations over the past few decades has been proposed to be a consequence of diet and lifestyle changes. Vitamin B is present in the testes and has been suggested as an adjuvant nutritional therapy for male infertility due to its potential to improve sperm parameters. However, evidence examining the relationship between vitamin B and reproductive hormones is limited.
The objective was to cross-sectionally examine the relationship between serum vitamin B and male reproductive hormones (luteinizing hormone, follicular stimulating hormone, total testosterone, estradiol, and prolactin).
Men with infertility (n = 303) were recruited from Mount Sinai Hospital in Toronto, Canada. Serum was analyzed for vitamin B and reproductive hormones. Statistical analyses included nonparametric Spearman's rank correlation coefficient, linear regression, logistic regression, and effect modification by age and BMI linear regressions.
An independent monotonic relationship between serum vitamin B and total testosterone (ρ = 0.19, P = 0.001) was observed. Serum vitamin B was linearly associated with total testosterone (unadjusted β = 0.0007, P = 0.008 and adjusted β = 0.0005, P = 0.03). Compared to individuals in the lowest tertile of serum vitamin B, those in the middle tertile (adjusted odds ratio [OR] = 0.48; 95% confidence interval [CI]: 0.25, 0.93, P = 0.03) and the highest tertile (unadjusted OR = 0.41; 95% CI: 0.22, 0.77, P = 0.005 and adjusted OR = 0.44; 95% CI: 0.22, 0.87, P = 0.02) had reduced odds of testosterone deficiency.
These findings suggest that among men with infertility, low serum vitamin B is associated with a higher risk of testosterone deficiency and impaired androgenic hormonal profiles that impact spermatogenesis and consequently, fertility.
不孕不育影响了北美 16%的夫妇，其中男性因素导致的不孕不育约占 30%。生殖激素，尤其是睾酮，对精子发生至关重要。过去几十年，人群中睾酮浓度呈与年龄无关的下降趋势，这种下降被认为是饮食和生活方式改变的结果。维生素 B 存在于睾丸中，因其有可能改善精子参数而被提议作为男性不育的辅助营养疗法。然而，关于维生素 B 与生殖激素之间关系的证据有限。
本研究旨在横断面研究血清维生素 B 与男性生殖激素（黄体生成素、卵泡刺激素、总睾酮、雌二醇和催乳素）之间的关系。
从加拿大多伦多西奈山医院招募了 303 名患有不育症的男性。分析血清中的维生素 B 和生殖激素。统计分析包括非参数 Spearman 秩相关系数、线性回归、逻辑回归以及年龄和 BMI 线性回归的效应修饰。
血清维生素 B 与总睾酮之间存在独立的单调关系（ρ=0.19，P=0.001）。血清维生素 B 与总睾酮呈线性相关（未校正β=0.0007，P=0.008；校正β=0.0005，P=0.03）。与血清维生素 B 最低三分位的个体相比，中三分位（校正比值比[OR] = 0.48；95%置信区间[CI]：0.25，0.93，P=0.03）和最高三分位（未校正 OR = 0.41；95% CI：0.22，0.77，P=0.005；校正 OR = 0.44；95% CI：0.22，0.87，P=0.02）的男性患睾酮缺乏症的风险降低。
这些发现表明，在患有不育症的男性中，血清维生素 B 水平低与睾酮缺乏症风险增加以及雄激素激素谱受损相关，后者影响精子发生，进而影响生育能力。
