D-aspartic acid and L-aspartic acid are the two naturally occurring forms of the amino acid aspartic acid.[1] Both are synthesized in the human body, they are also obtained through the diet via any dietary protein source.[1][2] While L-aspartic acid is used as a protein building block, D-aspartic acid is not.[1] Instead, D-aspartic acid has direct effects on the central nervous system and endocrine tissues.[1][3][4] This is why D-aspartic acid is also sold as a dietary supplement.
What is D-aspartic acid?
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•Last Updated: May 16, 2025
D-aspartic acid is 1 of the 2 naturally occurring forms of the amino acid aspartic acid; it is synthesized in the body and obtained from dietary protein sources. Unlike L-aspartic acid, which serves as a protein building block, D-aspartic acid affects the central nervous system and endocrine tissues, which has led to its availability as a dietary supplement.