Nelson Vergel
Founder, ExcelMale.com
"Smoking is positively and significantly associated with TT (total testosterone) and FT (free testosterone) levels in men in the FAMHES, even after adjusting for age, BMI, fasting blood glucose, triglycerides, alcohol consumption and estradiol level. The mechanism mediating the effect of smoking on testosterone production remains unclear. Several studies have reported that smoking may affect testosterone production not only by chronic mechanisms but also by acute ones. More specifically, Krsmanovic et al have demonstrated that smoking could stimulate acutely the release of gonadotropin-releasing hormone (GnRH) and LH.[SUP]42,43[/SUP] Moreover, it has also been suggested that smoking can increase testosterone levels by reducing the conversion of testosterone to estradiol.[SUP]44,45[/SUP] Additionally, the effects of smoking on testosterone levels have been found to be related to the personal smoking history, and TT and FT levels appeared to be inversely associated with pack-years of smoking in our study. Therefore, it is possible that the effect of smoking on testosterone levels is also mediated indirectly through other mechanisms. Yardimci et al studied the effects of long-term cigarette smoking on Leydig cells and found that cigarette smoking reduces testosterone biosynthesis.[SUP]46[/SUP] Their finding implied that smoking could lead to a gradual decrease in TT levels following long-term exposure, which may be related to the toxic effects of smoke on Leydig cells.[SUP]46
http://www.hormones.gr/8449/article/cigarette-smoking-has-a-positive-and….html
However, this study contradicts this data:
[/SUP][h=2]Smoking is associated with altered semen quality and endocrine hormonal status[/b]
