D-Aspartic Acid
Amino Acid ·Exploratory record · not publication-reviewed ·Updated July 13, 2026
Amino acid isomer studied for male fertility and testosterone, with inconsistent human evidence and no reliable testosterone benefit in healthy or resistance-trained men.
Exploratory record, not a reviewed medical publication.
See the editorial and medical-review policies for the publication gate.
This generated database record has not completed a claim-level review by a qualified human medical reviewer. Bibliography links and evidence labels are not approval. The page remains available for reference and is excluded from search indexing.
What the research says.
A quick, data-only summary. The full evidence, dosing, and sources are below.
D-Aspartic Acid is an amino acid most often used for fertility support (limited evidence in infertile men). NutriStack rates the overall evidence as emerging. A typical adult dose is 2-3 g daily for 2-3 week cycles, commonly taken as d-aspartic acid powder (sodium salt). This profile indexes 16 sources.
The bottom line
Evidence rating emerging. Most-documented uses: fertility support (limited evidence in infertile men). 16 sources indexed (2005–2025), with 0 interaction records on file.
How it works, mechanistically.
Core mechanism
Animal and mechanistic studies suggest hypothalamic-pituitary-gonadal effects, but human trials have not consistently shown increased LH or testosterone.12,15
Dosing & protocol.
What it actually costs.
Real-world pricing across three quality tiers. Assumes D-Aspartic Acid Powder.
Assumes 2-3 g/day during short cycles. Vendor basis: BulkSupplements powder, NOW Sports/iHerb, Vitacost, and Amazon marketplace; capsule formats raise daily cost. Updated 2026-05-28.
The same dose, as food.
How much you'd eat to match a supplemental dose.
Foods provide mixed amino acid proteins; a direct D-aspartic-acid food equivalent is not practical.
Full safety detail.
Sources, by evidence tier.
Numbered references. Citations throughout the page link here.
Meta-analyses & systematic reviews
4- 1Clinical Effectiveness of N-Methyl-D-Aspartate (NMDA) Receptor Antagonists in Adult Obsessive-Compulsive Disorder (OCD) Treatment: A Systematic ReviewPMIDFerguson AA, Khan AI, Abuzainah B et al. · Cureus · 2023
Ferguson AA, Khan AI, Abuzainah B et al.. Clinical Effectiveness of N-Methyl-D-Aspartate (NMDA) Receptor Antagonists in Adult Obsessive-Compulsive Disorder (OCD) Treatment: A Systematic Review. Cureus. 2023
- 2Antibodies against N-Methyl D-Aspartate Receptor in Psychotic Disorders: A Systematic ReviewPMIDMurashko AA, Pavlov KA, Pavlova OV et al. · Neuropsychobiology · 2022
Murashko AA, Pavlov KA, Pavlova OV et al.. Antibodies against N-Methyl D-Aspartate Receptor in Psychotic Disorders: A Systematic Review. Neuropsychobiology. 2022
- 3Use and Safety of Immunotherapeutic Management of N-Methyl-d-Aspartate Receptor Antibody Encephalitis: A Meta-analysisPMIDNosadini M, Eyre M, Molteni E et al. · JAMA neurology · 2021
Nosadini M, Eyre M, Molteni E et al.. Use and Safety of Immunotherapeutic Management of N-Methyl-d-Aspartate Receptor Antibody Encephalitis: A Meta-analysis. JAMA neurology. 2021
- 4N-Methyl-D-Aspartate antagonists in levodopa induced dyskinesia: a meta-analysisPMIDElahi B, Phielipp N, Chen R · The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques · 2012
Elahi B, Phielipp N, Chen R. N-Methyl-D-Aspartate antagonists in levodopa induced dyskinesia: a meta-analysis. The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques. 2012
Randomized controlled trials
5- 5Evaluation of in vivo supplementation of 2660 mg D-aspartic acid and 200 mg ubiquinol and 10 mg zinc on different semen parameters in idiopathic male infertility: a randomized double blind placebo controlled studyPMIDNot specified et al. · Eur Rev Med Pharmacol Sci · 2025
A combination of D-aspartic acid, ubiquinol, and zinc improved semen parameters in infertile men; this does not establish a general testosterone benefit for D-aspartic acid alone.
- 6The effects of d-aspartic acid supplementation in resistance-trained men over a three month training period: A randomised controlled trialPMIDMelville GW et al. · PLoS One · 2017
D-aspartic acid supplementation (6 g/day) is ineffective at changing testosterone levels or positively affecting training outcomes in resistance-trained men over 3 months.
- 7Three and six grams supplementation of d-aspartic acid in resistance trained menPMIDWilloughby DS et al. · J Int Soc Sports Nutr · 2015
Total testosterone was significantly reduced in men taking 6 g/day D-aspartic acid; free testosterone was also significantly reduced compared to placebo.
- 8The role and molecular mechanism of D-aspartic acid in the release and synthesis of LH and testosterone in humans and ratsSource linkedPMIDTopo E, Soricelli A, D'Aniello A et al. · Reprod Biol Endocrinol · 2009
- 9A randomized trial of an N-methyl-D-aspartate antagonist in treatment-resistant major depressionPMIDZarate CA Jr, Singh JB, Carlson PJ et al. · Archives of general psychiatry · 2006
Zarate CA Jr, Singh JB, Carlson PJ et al.. A randomized trial of an N-methyl-D-aspartate antagonist in treatment-resistant major depression. Archives of general psychiatry. 2006
Reviews & position papers
3- 10Anti-N-methyl-D-aspartate receptor-associated encephalitis: A review of clinicopathologic hallmarks and multimodal imaging manifestationsPMIDBeutler BD, Moody AE, Thomas JM et al. · World journal of radiology · 2024
Beutler BD, Moody AE, Thomas JM et al.. Anti-N-methyl-D-aspartate receptor-associated encephalitis: A review of clinicopathologic hallmarks and multimodal imaging manifestations. World journal of radiology. 2024
- 11N-methyl-d-aspartate (NMDA) receptor antagonists for treatment of catatonia in adults: Narrative reviewPMIDLee JH, Suzuki J · General hospital psychiatry · 2024
Lee JH, Suzuki J. N-methyl-d-aspartate (NMDA) receptor antagonists for treatment of catatonia in adults: Narrative review. General hospital psychiatry. 2024
- 12The putative effects of D-Aspartic acid on blood testosterone levels: A systematic reviewPMIDMelville GW et al. · J Int Soc Sports Nutr · 2017
Animal studies suggest reproductive-hormone effects, but human testosterone findings are inconsistent and the evidence remains sparse and low quality.
Observational studies
2- 13Electroconvulsive therapy in N-methyl-d-aspartate receptor encephalitis: A retrospective cohort and scoping review of literaturePMIDWright MA, Guasp M, Lachner C et al. · Journal of neuroimmunology · 2024
Wright MA, Guasp M, Lachner C et al.. Electroconvulsive therapy in N-methyl-d-aspartate receptor encephalitis: A retrospective cohort and scoping review of literature. Journal of neuroimmunology. 2024
- 14Occurrence of D-aspartic acid in human seminal plasma and spermatozoa: possible role in reproductionPMIDD'Aniello G et al. · Fertil Steril · 2005
D-aspartic acid concentration in seminal plasma was significantly reduced in oligoasthenoteratospermic men compared to normospermic donors, implicating D-Asp in male fertility.
Mechanistic & preclinical
1- 15Dietary supplementation with barley sprouts and d-aspartic acid improves reproductive hormone concentrations, testicular histology, antioxidant status, and mRNA expressions of apoptosis-related genes in aged broiler breeder roostersPMIDBarbarestani SY, Samadi F, Zaghari M, Pirsaraei ZA, Kastelic JP · Theriogenology · 2024
In aged broiler roosters, D-aspartic acid changed reproductive hormones and sperm measures; animal data should not be presented as human testosterone support.
Common questions.
Quick answers about D-Aspartic Acid, drawn from the data on this page.
What is D-Aspartic Acid?
Amino acid isomer studied for male fertility and testosterone, with inconsistent human evidence and no reliable testosterone benefit in healthy or resistance-trained men.
What is D-Aspartic Acid used for?
Commonly cited benefits of D-Aspartic Acid include: Fertility support (limited evidence in infertile men). NutriStack rates the overall evidence as emerging.
What is a typical dose of D-Aspartic Acid?
A typical adult dose of D-Aspartic Acid is 2-3 g daily for 2-3 week cycles. The commonly recommended form is D-Aspartic Acid powder (sodium salt). These are general ranges, not personalized advice; confirm the right dose with a clinician.
What are the side effects of D-Aspartic Acid?
Reported side effects include irritability, headache, acne, estrogen increase (via aromatase). This is educational information; check with a healthcare professional before use.
How strong is the evidence for D-Aspartic Acid?
NutriStack rates this as Emerging, meaning early RCT signal, mechanistic data, or limited human evidence. Full tier criteria are at https://nutristackapp.com/methodology/evidence-tiers.
Use this with your stack
D-Aspartic Acid in NutriStack.
Add it to your stack, see how it interacts with everything else you take, and get a Stack Score that updates the moment it does.