Testosterone & Hormonal
D-Aspartic Acid (DAA)
Also known as: DAA · D-Asp · Sodium D-aspartate
A naturally occurring amino acid that stimulates LH and testosterone release in untrained or older men. Evidence in trained athletes is inconsistent — testosterone may already be at ceiling.
Effective Dose
2000–3000mg / day
per clinical evidence
Evidence Level
Limited
Testosterone & Hormonal
Mechanism
NMDA receptor agonism in hypothalamus → GnRH → LH → testosterone
primary action
Best For
Testosterone support
Fertility
This profile is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications.
What Is D-Aspartic Acid (DAA)?
D-aspartic acid (the D-isomer of aspartate) is found naturally in the neuroendocrine system and reproductive tissues. It acts on NMDA receptors in the hypothalamus to stimulate GnRH release, which drives LH and subsequent testosterone production in Leydig cells. Effects are most pronounced in men with lower baseline testosterone.
How It Works: The Science
DAA accumulates in the hypothalamic-pituitary axis and testes, stimulating GnRH pulsatility (via NMDA receptor activation), increasing LH and FSH secretion, and directly stimulating testosterone synthesis in Leydig cells via StAR protein upregulation. Aromatase activity may also increase — some studies show co-elevation of oestradiol.
Primary Mechanism
NMDA receptor agonism in hypothalamus → GnRH → LH → testosterone
Evidence-Based Benefits
Dosage Guide
Effective Dose
2000–3000mg / day
2000–3000mg/day. Cycling recommended (3 weeks on, 1 week off) — T may return to baseline or below with chronic use as the HPG axis adapts.
Safety Profile & Side Effects
Generally safe. May increase oestradiol alongside testosterone — monitor if sensitive to oestrogen-related effects. Inconsistent results in trained athletes with normal testosterone levels.
Who Should (and Shouldn't) Take It
Untrained or older men with below-normal testosterone who want to increase it naturally. Trained athletes with normal T likely see minimal benefit.
Frequently Asked Questions
Related Ingredients
Medical Disclaimer
Ingredient profiles are for informational purposes only and do not constitute medical advice. Consult a qualified healthcare professional before starting any supplementation, especially if you have pre-existing conditions or take medications. Full disclaimer →