One substance that people overlook a lot are 5-AR inhibitors. They decrease the conversion of testosterone to dihydrotestosterone, thereby increasing testosterone levels.
There's a misconception that DHT is a more potent form of testosterone but this has never been proven. In fact, in adults DHT has essentially no benefit and only adverse effects like
- Increased sebum production (oily skin)
- Enlarged prostate
- Hair loss
- Even heart issues
Example:
Design, Setting, and Patients The 5α-Reductase Trial was a randomized controlled trial of healthy men aged 18 to 50 years comparing placebo plus testosterone enthanate with dutasteride plus testosterone enanthate from May 2005 through June 2010.
Conclusion Changes in fat-free mass in response to graded testosterone doses did not differ in men in whom DHT was suppressed by dutasteride from those treated with placebo, indicating that conversion of testosterone to DHT is not essential for mediating its anabolic effects on muscle.
https://jamanetwork.com/journals/jama/fullarticle/1105045
Dutasteride, a dual 5-AR inhibitor (type A and type B), increased testosterone levels and even increased weight loss in men:
Our results show that dutasteride treatment in men with BPH led to a significant increase in serum testosterone level and a significant decrease in BMI among those with relatively lower baseline serum testosterone levels.
https://pubmed.ncbi.nlm.nih.gov/19793378/