Body weight, fat mass and fasting insulin levels were increased by overfeeding (P,0.01) and insulin was increased significantly more in FH+ men (P,0.01). Serum sex hormone binding globulin (SHBG) and 5α-dihydrotestosterone (DHT) were reduced with overfeeding (P,0.05), and serum testosterone and DHT were reduced to a greater extent in FH+ men (P,0.05). Overfeeding reduced mRNA expression of 3β-hydroxysteroid dehydrogenase (HSD) and 17βHSD (P≤0.007), independently of group. 5α-Reductase (SRD5A1) mRNA expression was not changed overall, but a time by group interaction was observed (P=0.04).. ...