Androstenedione: Definition and Clinical Significance
Androstenedione is a naturally occurring steroid hormone that serves as a precursor to both testosterone and estrogen, but has limited clinical benefits while posing significant health risks when used as a supplement.
Biochemical Role and Natural Production
- Androstenedione is an endogenous steroid hormone produced in the gonads (testes and ovaries) and adrenal glands 1, 2
- It functions as a key intermediate in the biosynthetic pathway for both testosterone and estrogen production 2, 3
- Compared to testosterone and dihydrotestosterone (DHT), androstenedione is considered a less potent androgen 1
Marketed Uses and Claims
- Commonly marketed as "andro" to athletes and bodybuilders as a "natural alternative" to anabolic steroids 2, 4
- Supplement manufacturers claim it improves testosterone levels, increases muscle mass and strength, reduces body fat, enhances mood, and improves sexual performance 5, 2
- It has been aggressively marketed to the general public as a performance-enhancing supplement 5, 6
Scientific Evidence on Effectiveness
- Despite marketing claims, most scientific studies contradict the purported benefits of androstenedione supplementation 5, 4
- Research indicates that androstenedione supplementation does not significantly increase strength, lean body mass, or athletic performance 4, 6
- When administered orally to postmenopausal women, androstenedione does increase serum testosterone and estrone levels, but not estradiol levels 3
Health Risks and Side Effects
- Androstenedione supplementation can abnormally elevate estrogen-related hormones, potentially increasing risk for prostate or pancreatic cancers 5
- Studies show significant declines in high-density lipoproteins (HDL) with use, leading to increased cardiovascular disease risk 5, 6
- Supplementation may cause virilizing effects in women, including hirsutism 4, 3
- The long-term health effects of prolonged androstenedione supplementation remain largely unknown 7, 5
Regulatory Status
- Androstenedione is listed among performance-enhancing drugs (PEDs) banned by the World Anti-Doping Agency and the International Olympic Committee 2
- In the United States, the Anabolic Steroid Control Act of 2004 classified androstenedione and 17 other steroids as controlled substances 6
- As of January 2005, these substances cannot be sold without prescription in the United States 6
Clinical Monitoring and Testing
- Androstenedione can be measured in serum as part of the evaluation of reproductive endocrine disorders 1
- Normal reference ranges vary by laboratory, but elevated levels (>10.0 nmol/L) may warrant investigation for adrenal or ovarian tumors 1
- In clinical practice, androstenedione is sometimes measured alongside other hormones like testosterone, DHEAS, and LH/FSH when evaluating conditions like polycystic ovary syndrome (PCOS) 1
Alternative Approaches
- For those seeking to improve muscle mass and strength, evidence-based approaches include proper nutrition and resistance training 6
- For those with hormonal deficiencies, medically supervised hormone replacement therapy may be more appropriate 1, 7
- For female sexual dysfunction, FDA-approved medications like flibanserin or other approaches such as pelvic physical therapy may be more appropriate than androstenedione 7