Context: No large studies of young men have examined circulating sex hormones in relation to visceral and subcutaneous adipose tissues (VAT and SAT).

Objective: To investigate the role of VAT and SAT on circulating sex hormones and the impact of obesity on sex hormone reference-intervals.

Design, Setting, and Participants: Population-based study of 783 Danish, 20-29 year-old men employing dual-energy X-ray absorptiometry in all men and magnetic resonance imaging in 406 men.

Main Outcome Measures: Total, bioavailable, and free testosterone (TT, BT, FT), dihydrotestosterone (DHT), total and bioavailable estradiol (E₂ and BE₂), SHBG, and LH.

Results: In multiple regressions, VAT was an independent, inverse correlate of BT and FT. SAT correlated negatively with SHBG and positively with BE₂ adjusted for TT. Both VAT and SAT correlated inversely with TT and DHT: Adjusting for SHBG, only VAT remained significantly correlated. Low TT in viscerally obese men was not accompanied by increased LH. The androgen reference-intervals were significantly displaced towards lower limits in obese vs. non-obese men (TT: 8.5-29.3 nmol/l vs. 12.5-37.6 nmol/l; BT: 6.1-16.9 nmol/l vs. 7.6-20.7 nmol/l; FT: 0.29-0.78 nmol/l vs. 0.23-0.67 nmol/l; and DHT: 0.63-2.5 nmol/l vs. 0.85-3.2 nmol/l), while E₂ (36.5-166 pmol/l) and BE₂ (23.4-120 pmol/l) reference-intervals were not. In obese men, 22.9% had TT<12.5 nmol/l.

Conclusions: VAT correlate independently with BT and FT in young men. The inverse relationship between TT and SAT seems to be accounted for by variations in SHBG. The reference-intervals for TT, BT, FT, and DHT are displaced towards lower limits in obese men.