Hormone-related claims evidence brief
D-aspartic acid is an amino acid marketed for testosterone, fertility, strength, and muscle gain. The commercial claim is mainly hormone support.
Resistance-trained men are unlikely to see higher testosterone, strength, or muscle gain from D-aspartic acid.
Trained-men trial: 3 g no T effect; 6 g reduced total/free T by day 14.
Common studies use 3-6 g/day, but higher dosing has not solved the lack of useful sport outcomes.
Fertility or untrained-population findings do not validate broad testosterone or performance claims.
Source Drawer
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.
Send the disputed claim, source link, and why it changes the practical verdict. Corrections that materially affect the claim, dose, caveat, or rating are prioritized.
Report a source or rating issue