In young men, chronic ingestion of 100 mg androstenedione (ASD), three time
s per day, does not increase serum total testosterone but does increase ser
um estrogen and ASD concentrations. We investigated the effects of ASD inge
stion in healthy 30- to 56-yr-old men. In a double-blind, randomly assigned
manner, subjects consumed 100 mg ASD three times daily (n = 28), or placeb
o (n = 27) for 28 days. Serum ASD, dihydrotestosterone (DHT), free and tota
l testosterone, estradiol, prostate-specific antigen (PSA), and lipid conce
ntrations were measured at week 0 and each week throughout the supplementat
ion period. Serum total testosterone and PSA concentrations did not change
with supplementation. Elevated serum concentrations of ASD (300%), free tes
tosterone (45%), DHT (83%), and estradiol (68%) were observed during weeks
1-4 in ASD (P < 0.05). There was no relationship between age and changes in
serum ASD (r(2) = 0.024), free testosterone (r(2) = 0.00), or estradiol (r
(2) = 0.029) concentrations with ASD, whereas the serum DHT response to ASD
ingestion was related to age (r(2) = 0.244; P < 0.05). Serum concentration
s of high-density Lipoprotein cholesterol were decreased by 10% during the
supplementation period (P < 0.05). These results suggest that the ingestion
of 100 mg ASD, three times per day, does not increase serum total testoste
rone or PSA concentrations but does elicit increases in ASD, free testoster
one, estradiol, and DHT and decreases serum high-density lipoprotein choles
terol concentrations.