Effects of a high-fat diet on postabsorptive and postprandial testosterone responses to a fat-rich meal.
Postprandial testosterone concentrations have been shown to significantly decrease after a fat-rich meal, which may be due to inhibition of testosterone production by chylomicrons. We examined the effects of a high-fat diet known to reduce postprandial chylomicrons on the testosterone response to a fat-rich meal. Total testosterone (TT), free testosterone (FT), cortisol, and insulin responses to a high-fat test meal containing 5.44 MJ (1,300 kcal, 11% carbohydrate, 3% protein, 86% fat) were determined before (week 0) and after (week 8) an 8-week high-fat diet (64% fat) in 11 healthy men. The high-fat diet resulted in significant reductions in postabsorptive and postprandial serum triacylglycerols (55% and 50%, respectively). There were no significant changes in postabsorptive serum TT, FT, and cortisol, but insulin concentrations were significantly (P < or = .05) lower at week 8 (-28%). There was a significant reduction 1 hour after the fat-rich meal for TT (-22%) and FT (-23%), which remained significantly below baseline for 8 hours. Postprandial TT and FT responses were not significantly different after the 8-week high-fat diet. Postprandial serum cortisol concentrations were significantly reduced 1 hour after the meal. There were no significant differences before and after the high-fat diet. Insulin was significantly increased at the 0-, 1-, and 2-hour postprandial time points before and after the high-fat diet. Compared with week 0, insulin concentrations were significantly lower prior to and immediately after the fat-rich meal at week 8. These data indicate a fat-rich meal results in a prolonged reduction in TT and FT concentrations that is not altered by lowering postprandial chylomicrons. Alternative mechanisms (eg, higher uptake at the receptor level of cells) other than chylomicron-induced or insulin-induced inhibition of steroidogenesis are likely responsible for the reduction in TT and FT after a fat-rich meal.
Volek
J S
JS
Human Performance Laboratory, Ball State University, Muncie, IN 47306, USA.
Gómez
A L
AL
Love
D M
DM
Avery
N G
NG
Sharman
M J
MJ
Kraemer
W J
WJ
D000284:Administration, Oral; D000328:Adult; D002914:Chylomicrons / Q000097:blood; D004041:Dietary Fats; D005215:Fasting / Q000502:physiology*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007328:Insulin / Q000097:blood; D008055:Lipids / Q000008:administration & dosage*; D008297:Male; D019518:Postprandial Period / Q000502:physiology*; D013739:Testosterone / Q000097:blood*; D013997:Time Factors; D014280:Triglycerides / Q000097:blood; D044465:White People
D002914:Chylomicrons; D004041:Dietary Fats; D007328:Insulin; D008055:Lipids; D014280:Triglycerides; D013739:Testosterone; D006854:Hydrocortisone