D-aspartic acid (D-AA) is an amino acid regulator of testosterone synthesis and may act on a stimulatory receptor (NMDA). D-AA shows promise in aiding male fertility. Healthy men supplementing D-AA experience only temporary increases in testosterone, which limits its use.
D-Aspartic Acid is most often used for
D-aspartic acid is one of two forms of the amino acid aspartic acid. The other form is L-aspartate.
The benefits of D-AA are specific to it, and do not extend to aspartic acid or L-aspartate.
D-AA can be used as a testosterone booster for infertile men, and by athletes as a temporary booster. Elevated testosterone levels only last a week to a week and a half in healthy men, with testosterone returning to normal afterward.
D-AA works in the central brain region to cause a release of hormones, such as luteinizing hormone, follicle-stimulating hormone, and growth hormone. It may also build up in the testicles, where it alleviates a rate-limiting step of testosterone synthesis, which leads to a minor testosterone increase.
Further research is needed on D-AA, as most studies attempt to assess D-AA’s role in the body under normal conditions, and not in the frame of supplementation.
The standard dose for D-aspartic acid is between 2,000 – 3,000mg.
D-AA is taken daily.
Different studies have used different supplementation protocols. One study used 3,000mg for 12 days, taken daily, followed by a week with no supplementation. A different study did not cycle D-AA, and used 2,000mg of continual daily supplementation with no harm. Further study is needed to determine whether D-AA should be cycled.
It is possible that ZMA can cause weird dreams, and the anecdotes support this; however, since this has not been directly investigated the best 'proof' that can be given is weak.
This claim has not been investigated much, but a pilot study suggests that a dose of 250mg pyridoxine can alter dream perception in college aged men, through a hypothesized increased conversion of tryptophan to serotonin. This dose of B6, however, is much higher than that occurring in ZMA products; which tends to range in the 10-50mg range and usually at the lower end.
One other study has reported synergism between B6 and Magnesium in regards to anxiety reduction, when the subjects were women experiencing PMS; it is theoretically possible that the ZMA formulation enhances the actions of pyridoxine allowing the previous research's results to be relevant.