From the Guidelines
The most effective supplements for increasing testosterone levels in humans are zinc, ashwagandha, and vitamin D3, with zinc supplementation (25-45 mg daily) and ashwagandha (300-600 mg daily of root extract) showing significant improvements in testosterone levels within 1-3 months and 8-12 weeks, respectively, as supported by human clinical trials 1.
Key Findings
- Zinc supplementation can increase testosterone in zinc-deficient men, with studies showing improvements within 1-3 months 1.
- Ashwagandha has demonstrated testosterone increases of 10-22% in human clinical trials over 8-12 weeks, particularly in men with stress or infertility issues 1.
- Vitamin D3 can boost testosterone by 20-30% in deficient individuals after 3-12 months 1.
- Magnesium bisglycinate has moderate human evidence suggesting it may maintain testosterone levels, especially during exercise 1.
- Boron has limited but promising human data showing potential increases after 1-2 months 1.
- Tongkat ali has mixed human evidence but may benefit men with low testosterone or stress 1.
- Fadogia agrestis has only animal data and lacks safety information for humans, making it inadvisable for use 1.
Recommendations
- Address any nutritional deficiencies first, particularly zinc and vitamin D, as these have the strongest connection to testosterone production.
- Consider ashwagandha and magnesium bisglycinate as potential supplements to support testosterone levels.
- Be cautious when using boron and tongkat ali due to limited human evidence.
- Avoid using Fadogia agrestis due to lack of human safety data.
Mechanisms
- These supplements work by supporting various aspects of testosterone synthesis, including enzyme function, stress reduction, and hormone conversion pathways.
- Effects are typically modest compared to pharmaceutical interventions and most beneficial for those with deficiencies or suboptimal levels 1.
From the Research
Efficacy of Zinc on Testosterone Levels
- Zinc deficiency has been shown to reduce testosterone levels, while zinc supplementation can improve testosterone levels 2
- The effect of zinc on serum testosterone may vary depending on basal zinc and testosterone levels, zinc dosage form, elementary zinc dose, and duration 2
- However, excessive intake of zinc can have negative effects, such as increasing the risk of advanced prostate cancer, inhibiting the benefits of bisphosphonate drugs, and promoting immune dysfunction 3
Efficacy of Tongkat Ali on Testosterone Levels
- Tongkat Ali has been shown to stimulate the release of free testosterone, improve sex drive, reduce fatigue, and improve well-being 4
- A study found that daily supplementation with Tongkat Ali root extract improved stress hormone profile and certain mood state parameters, with reduced cortisol exposure and increased testosterone status [+37%] 4
- Another study found that a 200 mg supplement of Tongkat Ali, combined with concurrent training, significantly improved erectile function and increased total testosterone levels in men with androgen deficiency of aging males (ADAM) 5
Efficacy of Zinc and Selenium Supplementation on Testosterone Levels
- A study found that 4-week simultaneous and separate zinc and selenium supplementation had no significant effect on resting testosterone and lactate levels in subjects who consume a zinc and selenium sufficient diet 6
- However, the study found that serum total testosterone levels in the zinc group were higher than in the selenium group after exercise, and serum-free testosterone levels in the zinc group were higher than the other groups 6
Other Substances
- There is no available evidence in the provided studies to support the efficacy of Fadogia agrestis, Ashwagandha (Withania somnifera), magnesium bisglycinate, vitamin D3, and boron on increasing testosterone levels in humans or animals.