6-OXO IS PROVEN TO BE SAFE, EFFECTIVE AT RAISING TESTOSTERONE AND LOWERING AROMATASE ACTIVITY.
Effects of eight weeks of an alleged aromatase inhibiting nutritional supplement 6-OXO (androst-4-ene-3,6,17-trione) on serum hormone profiles and clinical safety markers in resistance-trained, eugonadal males
Dan Rohle1 ,
Colin Wilborn2 ,
Lem Taylor3 ,
Chris Mulligan4 ,
Richard Kreider5 and
Darryn Willoughby5,6
1 Pharmacology Department, Weill Cornell Graduate School of Medical Sciences, 445 East 69th Street, Room 412, New York, NY 10021, USA
2 Department of Exercise and Sport Science, University of Mary Hardin-Baylor, UMHB Station, 900 College Box 8010, Belton, Texas 76513, USA
3 Department of Health, Leisure, and Exercise Science, University of West Florida, 11000 University Parkway, # 72-219, Pensacola, FL 32514, USA
4 Department of Nutrition and Food Science, Colorado State University, Fort Collins, CO 80523, USA
5 Department of Health, Human Performance, and Recreation, Baylor University, Box 97313, Waco, TX 76798, USA
6 Institute for Biomedical Studies, Baylor University, Waco, TX 76798, USA
Journal of the International Society of Sports Nutrition 2007,
4:13doi:10.1186/1550-2783-4-13
The electronic version of this article is the complete one and can be found online at:
Journal of the International Society of Sports Nutrition | Full text | Effects of eight weeks of an alleged aromatase inhibiting nutritional supplement 6-OXO (androst-4-ene-3,6,17-trione) on serum hormone profiles and clinical safety markers in resis
Received:25 September 2007Accepted:19 October 2007Published:19 October 2007
© 2007 Rohle et al; licensee BioMed Central Ltd.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (
Creative Commons — Attribution 2.0 Generic — CC BY 2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract
The purpose of this study was to determine the effects of 6-OXO, a purported nutritional aromatase inhibitor, in a dose dependent manner on body composition, serum hormone levels, and clinical safety markers in resistance trained males. Sixteen males were supplemented with either 300 mg or 600 mg of 6-OXO in a double-blind manner for eight weeks. Blood and urine samples were obtained at weeks 0, 1, 3, 8, and 11 (after a 3-week washout period). Blood samples were analyzed for total testosterone (TT), free testosterone (FT), dihydrotestosterone (DHT), estradiol, estriol, estrone, SHBG, leutinizing hormone (LH), follicle stimulating hormone (FSH), growth hormone (GH), cortisol, FT/estradiol (T/E). Blood and urine were also analyzed for clinical chemistry markers. Data were analyzed with two-way MANOVA. For all of the serum hormones, there were no significant differences between groups (p > 0.05). Compared to baseline, free testosterone underwent overall increases of 90% for 300 mg 6-OXO and 84% for 600 mg, respectively (p < 0.05). DHT underwent significant overall increases (p < 0.05) of 192% and 265% with 300 mg and 600 mg, respectively. T/E increased 53% and 67% for 300 mg and 600 mg 6-OXO, respectively. For estrone, 300 mg produced an overall increase of 22%, whereas 600 mg caused a 52% increase (p < 0.05). Body composition did not change with supplementation (p > 0.05) and clinical safety markers were not adversely affected with ingestion of either supplement dose (p > 0.05).
While neither of the 6-OXO dosages appears to have any negative effects on clinical chemistry markers, supplementation at a daily dosage of 300 mg and 600 mg for eight weeks did not completely inhibit aromatase activity, yet significantly increased FT, DHT, and T/E.
