D-Aspartic Acid
D-aspartic acid is the mirror-image form of the amino acid aspartic acid. It occurs naturally in nerve and hormone-producing tissue and is mostly studied for testosterone.
Also listed as D-AA, D-Aspartate, DAA
What do we know about unwanted effects?
The systematic review records irritability, nervousness, rapid heart rate and headache in three participants in one trial. Small, short studies cannot establish long-term safety. The available male study populations also leave safety in pregnancy, breastfeeding and children unanswered. 1 2
The 12-week trial found lower estradiol without a testosterone increase. The clinical meaning was uncertain; a hormone moving downward is not automatically a health benefit. 1 2
Adverse findings
Ratings where the reported effect was unwanted. Each lists the studies behind it.
For information, not individual medical advice. Ingredient studies do not establish the effectiveness of these products.