D-Aspartic Acid

Last Updated: September 28 2022

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.

What else is D-Aspartic Acid known as?
Note that D-Aspartic Acid is also known as:
  • D-AA
  • D-Aspartate
  • DAA
D-Aspartic Acid should not be confused with:
  • DL-Aspartate
  • Aspartate
Dosage information

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.

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1.^Man EH, Bada JLDietary D-amino acidsAnnu Rev Nutr.(1987)
2.^Friedman MChemistry, nutrition, and microbiology of D-amino acidsJ Agric Food Chem.(1999 Sep)
4.^Maroudas A, Palla G, Gilav ERacemization of aspartic acid in human articular cartilageConnect Tissue Res.(1992)
6.^Man EH, Sandhouse ME, Burg J, Fisher GHAccumulation of D-aspartic acid with age in the human brainScience.(1983 Jun 24)
7.^Perna AF, D'Aniello A, Lowenson JD, Clarke S, De Santo NG, Ingrosso DD-aspartate content of erythrocyte membrane proteins is decreased in uremia: implications for the repair of damaged proteinsJ Am Soc Nephrol.(1997 Jan)
8.^Hashimoto A, Kumashiro S, Nishikawa T, Oka T, Takahashi K, Mito T, Takashima S, Doi N, Mizutani Y, Yamazaki T, et alEmbryonic development and postnatal changes in free D-aspartate and D-serine in the human prefrontal cortexJ Neurochem.(1993 Jul)
9.^Fisher GH, D'Aniello A, Vetere A, Padula L, Cusano GP, Man EHFree D-aspartate and D-alanine in normal and Alzheimer brainBrain Res Bull.(1991 Jun)
12.^Lee JA, Homma H, Tashiro K, Iwatsubo T, Imai KD-aspartate localization in the rat pituitary gland and retinaBrain Res.(1999 Aug 14)
13.^Imai K, Fukushima T, Hagiwara K, Santa TOccurrence of D-aspartic acid in rat brain pineal glandBiomed Chromatogr.(1995 Mar-Apr)
14.^Lee JA, Homma H, Sakai K, Fukushima T, Santa T, Tashiro K, Iwatsubo T, Yoshikawa M, Imai KImmunohistochemical localization of D-aspartate in the rat pineal glandBiochem Biophys Res Commun.(1997 Feb 13)
17.^D'Aniello A, Di Cosmo A, Di Cristo C, Annunziato L, Petrucelli L, Fisher GInvolvement of D-aspartic acid in the synthesis of testosterone in rat testesLife Sci.(1996)
18.^Sakai K, Homma H, Lee JA, Fukushima T, Santa T, Tashiro K, Iwatsubo T, Imai KLocalization of D-aspartic acid in elongate spermatids in rat testisArch Biochem Biophys.(1998 Mar 1)
19.^Topo E, Soricelli A, D'Aniello A, Ronsini S, D'Aniello GThe role and molecular mechanism of D-aspartic acid in the release and synthesis of LH and testosterone in humans and ratsReprod Biol Endocrinol.(2009 Oct 27)
21.^Pampillo M, Scimonelli T, Bottino MC, Duvilanski BH, Rettori V, Seilicovich A, Lasaga MThe effect of D-aspartate on luteinizing hormone-releasing hormone, alpha-melanocyte-stimulating hormone, GABA and dopamine releaseNeuroreport.(2002 Dec 3)
23.^Lamanna C, Assisi L, Botte V, Di Fiore MMInvolvement of D-Asp in P450 aromatase activity and estrogen receptors in boar testisAmino Acids.(2007 Jan)
24.^Assisi L, Botte V, D'Aniello A, Di Fiore MMEnhancement of aromatase activity by D-aspartic acid in the ovary of the lizard Podarcis s. siculaReproduction.(2001 May)
25.^Raucci F, D'Aniello S, Di Fiore MMEndocrine roles of D-aspartic acid in the testis of lizard Podarcis s. siculaJ Endocrinol.(2005 Dec)
26.^D'Aniello S, Somorjai I, Garcia-Fernàndez J, Topo E, D'Aniello AD-Aspartic acid is a novel endogenous neurotransmitterFASEB J.(2011 Mar)
28.^Davies LP, Johnston GAUptake and release of D- and L-aspartate by rat brain slicesJ Neurochem.(1976 May)
30.^Erreger K, Geballe MT, Kristensen A, Chen PE, Hansen KB, Lee CJ, Yuan H, Le P, Lyuboslavsky PN, Micale N, Jørgensen L, Clausen RP, Wyllie DJ, Snyder JP, Traynelis SFSubunit-specific agonist activity at NR2A-, NR2B-, NR2C-, and NR2D-containing N-methyl-D-aspartate glutamate receptorsMol Pharmacol.(2007 Oct)
31.^Topo E, Soricelli A, Di Maio A, D'Aniello E, Di Fiore MM, D'Aniello AEvidence for the involvement of D-aspartic acid in learning and memory of ratAmino Acids.(2010 May)
36.^Sugawara T, Lin D, Holt JA, Martin KO, Javitt NB, Miller WL, Strauss JF 3rdStructure of the human steroidogenic acute regulatory protein (StAR) gene: StAR stimulates mitochondrial cholesterol 27-hydroxylase activityBiochemistry.(1995 Oct 3)
37.^Caron KM, Ikeda Y, Soo SC, Stocco DM, Parker KL, Clark BJCharacterization of the promoter region of the mouse gene encoding the steroidogenic acute regulatory proteinMol Endocrinol.(1997 Feb)
39.^D'Aniello G, Ronsini S, Guida F, Spinelli P, D'Aniello AOccurrence of D-aspartic acid in human seminal plasma and spermatozoa: possible role in reproductionFertil Steril.(2005 Nov)
41.^D'Aniello G, Grieco N, Di Filippo MA, Cappiello F, Topo E, D'Aniello E, Ronsini SReproductive implication of D-aspartic acid in human pre-ovulatory follicular fluidHum Reprod.(2007 Dec)
43.^Furuchi T, Homma HFree D-aspartate in mammalsBiol Pharm Bull.(2005 Sep)
44.^Lee JA, Long Z, Nimura N, Iwatsubo T, Imai K, Homma HLocalization, transport, and uptake of D-aspartate in the rat adrenal and pituitary glandsArch Biochem Biophys.(2001 Jan 15)
45.^Long Z, Lee JA, Okamoto T, Nimura N, Imai K, Homma Hd-Aspartate in a prolactin-secreting clonal strain of rat pituitary tumor cells (GH(3))Biochem Biophys Res Commun.(2000 Oct 5)
46.^D'Aniello G, Tolino A, D'Aniello A, Errico F, Fisher GH, Di Fiore MMThe role of D-aspartic acid and N-methyl-D-aspartic acid in the regulation of prolactin releaseEndocrinology.(2000 Oct)
47.^Ishio S, Yamada H, Hayashi M, Yatsushiro S, Noumi T, Yamaguchi A, Moriyama YD-aspartate modulates melatonin synthesis in rat pinealocytesNeurosci Lett.(1998 Jun 19)
48.^Yamada H, Yamaguchi A, Moriyama YL-aspartate-evoked inhibition of melatonin production in rat pineal glandsNeurosci Lett.(1997 Jun 6)
50.^Kim MH, Uehara S, Muroyama A, Hille B, Moriyama Y, Koh DSGlutamate transporter-mediated glutamate secretion in the mammalian pineal glandJ Neurosci.(2008 Oct 22)
51.^Yamada H, Yatsushiro S, Yamamoto A, Hayashi M, Nishi T, Futai M, Yamaguchi A, Moriyama YFunctional expression of a GLT-1 type Na+-dependent glutamate transporter in rat pinealocytesJ Neurochem.(1997 Oct)
53.^Errico F, Pirro MT, Affuso A, Spinelli P, De Felice M, D'Aniello A, Di Lauro RA physiological mechanism to regulate D-aspartic acid and NMDA levels in mammals revealed by D-aspartate oxidase deficient miceGene.(2006 Jun 7)