T Nation

D-Aspartic Acid & Other D-Form Aminos


I've been reading some info on the studies being performed with DAA or D-Aspartic Acid. Apparently when early biological studies seemed to show that there were few to no benefits to tested organisms taking D-form aminos they were not seen as valid.

However recent tests seem to show a marked uptick in Testosterone production as a result of 3 grams or greater suplementation daily of DAA. Is anyone else here following this as a supplement or the research??


It looks like at least a few companies are rushing to market with products that either are straight DAA or a blend of it with other things.

I've so far read about a dozen articles about it and the testing so far performed on rats, humans, etc.

None of them seemed absolutely conclusive that all the effects were beneficial, and I have not as of yet found the illusive '40% increase in testosterone production in men 27 - 37' article. That's the claim that is piquing everyone's interest.

Any of you mods know if the powers that be at tmuscle are looking into it yet?


Supposedly it's a potent test booster. Yes, the study(ies?) showed a 40% boost to test in 8 weeks @3 grams per day. Although not steroid like that's pretty good, and I doubt it would cause shut down. And for the price, a cycle is more affordable than a cycle of most of the alternatives (about $50 for an 8 week run (plus the cost of food, lol)).

I've seen nothing but good things about this supplement. I think Biotest is even looking into it at the moment although i can't officially comment on this or what their thoughts might be, not that if I did would i have any credibility :stuck_out_tongue: TC if you're around maybe you have a comment.


Patrick Arnold has written a lot about it recently. He's also saying that a lot of asian suppliers are selling supp companies L-aspartic acid (the shit version) and the supp companies are getting fucked over.


Yeah that's the scuttle butt I've been hearing to. And without a lab to test how would you know what you were getting or then selling to your customers?

I'm sure it will be gonzo awesome if TMUSCLE decides to do it, and they'll make sure it's right, but I'm skiddish about dropping any serious money on the first adopter types.


Yeah it would be cool to hear what TC or Tim think about this...




I just bought some from nutraplanet. I'll let you guys know if I got ripped off or if I got a legit batch.


Do you have access to a polarimeter? That's about the only way to differentiate the two isomers.


I've twice mentioned this a couple weeks ago but there wasnt much response... glad to see this thread getting action!


I'm afraid I don't. I'm not too worried about it, so I'll stick with how it affects me, but thanks for the suggestion.


Well I did a site search on tmuscle before starting the thread and didn't see too much out there so I'm hoping I haven't stepped on anyone else, but I thought the proposed benefits looked cool enough to open it for dialouge.

A few of the other benefits seem to be cognitive. Apparently there are high concentrations of DAA naturally occuring in white and grey matter in the human brain.

If it is even half of what they claim it looks to be very beneficial. Biotest already has ties to reputable suppliers so I'm sure they could put something out there that would be above suspicion.


I found a study about it. It used ducks, but they say that the results are similar for all vertebrates:


I'll be interested in hearing folks' results with DAA supplementation.


WOW. Notice not only what the study says about DAA, but what it says about NO. Wonder if the guys taking NO Explode know about that?



Yes, we (Biotest) are looking into aspartic acid among other things. Here is the link to the human study:


Also, 40% may not seem like a big increase, but when timed properly it may help upregulate androgen receptors. For example:

J Steroid Biochem Mol Biol. 2009 Apr;114(3-5):195-9. Epub 2009 Feb 21.
Elevated endogenous testosterone concentrations potentiate muscle androgen receptor responses to resistance exercise.

Spiering BA, Kraemer WJ, Vingren JL, Ratamess NA, Anderson JM, Armstrong LE, Nindl BC, Volek JS, Häkkinen K, Maresh CM.

Department of Kinesiology, University of Connecticut, 2095 Hillside Road, Storrs, CT 06269, USA.

The purpose of this study was to determine the influence of endogenous circulating testosterone (T) on muscle androgen receptor (AR) responses to acute resistance exercise (RE). Six healthy men (26+/-4 years; 176+/-5 cm; 75.8+/-11.4 kg) performed a knee extension exercise protocol on two occasions separated by 1-3 weeks. Rest preceded one trial (i.e., control [CON] trial) and a high-volume upper-body RE protocol designed to increase circulating T preceded the other trial (i.e., high T [HT] trial). Serial blood samples were obtained throughout each trial to determine circulating T concentrations. Biopsies of the vastus lateralis were obtained pre-RE (REST), 10-min post-RE (+10), and 180-min post-RE (+180) to determine muscle AR content. Circulating T concentrations remained stable during CON. Alternately, HT significantly (p< or =0.05) increased T concentrations above resting values (+16%). Testosterone area-under-the-time curve during HT exceeded CON by 14%. AR content remained stable from REST to +10 in both trials. Compared to the corresponding +10 value, muscle AR content at +180 tended to decrease during CON (-33%; p=0.10) but remained stable during HT (+40%; p=0.17). Muscle AR content at +180 during the HT trial exceeded the corresponding CON value. In conclusion, acute elevations in circulating T potentiated muscle AR content following RE.

Over time, I would expect an effect like that to improve training adaptations.



P.S. I would expect Alpha Male to result in similar changes in serum testosterone...


Sure thing. Definitely interested in hearing your results with it.


Dr. Z,

Thanks for the update. The stuff looks promising and I can't wait to see what Biotest does with it!

If you have looked into it, can you comment on whether there is potential for competition for absorption of this amino acid if taken with other aminos/protein, meaning can this stuff be taken with food??. FWIW, E-pharm recently released their DAA product, and the directions say to take it on an empty stomach.

Also, I imagine that dosing this right before a workout would be beneficial, although given the empty stomach recommendations, I would think it would be pretty hard to do this, especially if on the anaconda protocol, since "take it on an empty stomach" usually means 30 min before other food.

maybe taking this in the morning with a carbohydrate and BCAA shake would be okay? Or do the branch chain amino transporters compete with those of D-asparate?

Also any other comments on the cognitive aspects if you or anyone else have any? Thanks!


Amazing. Thanks Tim.


I know that the Italians (D'Aniello and colleagues) who have done much of the pioneering research with D-Aspartate, have found it necessary to knock out the D-Aspartate Oxidase (the protein responsible for breaking down D-Asp) gene in order to keep D-Asp levels elevated in the mouse model they use. Oral administration alone over time causes an upregulation in the DAO gene, so effectively the brain is just breaking down the extra D-Asp being taken in. Of course, that is in mice. I imagine things would go about the same in humans, but who knows? But, my point is, if the brain is just breaking down all the extra D-Asp, then cognitive benefits in the long run will be minimal.