Association of serum α-tocopherol with sex steroid hormones and interactions with smoking: implications for prostate cancer risk.

Abstract

BACKGROUND:

Vitamin E may protect against prostate cancer, possibly only in smokers and, we hypothesize, through altered sex steroid hormones. A controlled trial in smokers showed that sex hormone levels were inversely associated with baseline serum α-tocopherol and decreased in response to vitamin E supplementation. The vitamin E-hormone relation is understudied in non-smokers.

METHODS:

Serum sex steroid hormones and α-tocopherol were measured for 1,457 men in NHANES III. Multivariable-adjusted geometric mean hormone concentrations by α-tocopherol quintile were estimated.

RESULTS:

We observed lower mean testosterone, estradiol, and SHBG concentrations with increasing serum α-tocopherol (Q1 = 5.5 and Q5 = 4.6 ng/ml, p-trend = 0.0007; Q1 = 37.8 and Q5 = 33.1 pg/ml, p-trend = 0.02; Q1 = 38.8 and Q5 = 30.6 pg/ml, p-trend = 0.05, respectively). Interactions between serum α-tocopherol and exposure to cigarette smoke for total testosterone, total estradiol, and SHBG were found with the inverse relation observed only among smokers.

CONCLUSIONS:

Results from this nationally representative, cross-sectional study indicate an inverse association between serum α-tocopherol and circulating testosterone, estradiol, and SHBG, but only in men who smoked. Our findings support vitamin E selectively influencing sex hormones in smokers and afford possible mechanisms through which vitamin E may impact prostate cancer risk.

• Authors: Alison M Mondul, Sabine Rohrmann, Andy Menke, Manning Feinleib, William G Nelson, Elizabeth A Platz, Demetrius Albanes
• Journal: Cancer causes & control : CCC (Cancer Causes Control) Vol. 22 Issue 6 Pg. 827-36 (Jun 2011) ISSN: 1573-7225 [Electronic] Netherlands
• PMID: 21424597 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Gonadal Steroid Hormones
• Sex Hormone-Binding Globulin
• Testosterone
• alpha-Tocopherol

Topics

• Adult
• Carcinoma (blood, epidemiology, ethnology, etiology)
• Cross-Sectional Studies
• Gonadal Steroid Hormones (blood)
• Humans
• Male
• Middle Aged
• Nutrition Surveys
• Prostatic Neoplasms (blood, epidemiology, ethnology, etiology)
• Risk Factors
• Sex Hormone-Binding Globulin (analysis)
• Smoking (adverse effects, blood, epidemiology)
• Testosterone (blood)
• Young Adult
• alpha-Tocopherol (blood)