1.5/5
Very weak
evidence
Testosterone booster evidence brief
D-aspartic acid
Resistance-trained men are unlikely to see higher testosterone, strength, or muscle gain from D-aspartic acid.
Headline Finding
Trained-men trial: 3 g no T effect; 6 g reduced total/free T by day 14.
Dose Context
Common studies use 3-6 g/day, but higher dosing has not solved the lack of useful sport outcomes.
Important Caveat
Fertility or untrained-population findings do not validate gym testosterone-booster claims.
Source Drawer
Linked Research
- Systematic review Testosterone boosters systematic review
- Trial Trained men 3g/6g trial
- Trial 12-week trained-men RCT
- Trial Male climbers trial
- Trial NMDA heavy-training trial
How To Read This Rating
The score reflects evidence that the supplement does its stated job. Some jobs are direct, such as strength, endurance, or recovery; others are indirect, such as sleep, mood, appetite, or health support. A real effect can still receive a cautious practical rating when dose, safety, product quality, or audience fit remain uncertain.
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