This is the only study I could find on humans!
The fact that “DADAVIT®” is featured all over the research paper, suggests it may have been sponsored, and therefore arguably not 100% reliable.
LH stands for – “Luteinizing hormone”. In men this hormone stimulates Leydig cell production of testosterone.
In this study 23 participants took an oral dose of sodium
D-aspartate – containing 3g D-Aspartic-Acid (DADAVIT®) for 12 consecutive days and 20 participants took an oral dose of placebo (DADAVIT® placebo) for 12 consecutive days; the levels of LH and testosterone in the serum were monitored after 6 and 12 days of treatment and 3 days after suspension of the treatment.
Concerning the LH pattern, the results demonstrated that after 12 days of D-Asp treatment, 20 out of 23 (87%) participants had significantly increased concentrations of LH. The increase was much greater after 12 days of supplementation, compared with 6 days.
Out of 23 participants, 20 had increased testosterone. From a mean of 4.5 ± 0.6 ng/ml serum at zero time, it rose to 6.4 ± 0.8 ng/ml, a 42% increase