There are few known side effects associated with D-aspartic acid supplementation.
However, there are no long-term studies DAA supplementation and the risk of side effects remains ill-defined.
Many use DAA to increase testosterone levels and boost athletic performance. Low testosterone affects millions of American men, especially those who are 45 and older.
Testosterone replacement injections are becoming increasingly popular in the United States, but may lead to side effects.
When testosterone injections are administered regularly, a feedback loop may be triggered where the body produces less testosterone. Over time, this may diminish natural testosterone production while doing nothing to address the underlying cause of low testosterone.
D-aspartic acid (DAA) is thought to encourage the body’s natural production of testosterone. However, it is unclear whether it may also cause side effects related to testosterone suppression with long-term use. For this reason, it is typically used for a maximum of three weeks at a time.



- Shown to increase testosterone production
- Supports athletic performance, fat loss & strength
- Boosts sexual health & libido
D-Aspartic Acid Guide
Related Topics
- What is D-Aspartic Acid?
- D-Aspartic Acid vs. L-Aspartic Acid
- DAA Supplements
- Aspartic Acid Supplements
- Effects and Benefits
- Recommended Dosages
- DAA and Testosterone
- DAA for Bodybuilding
- Results for Bodybuilders
- DAA Testosterone Booster
- Possible Side Effects
- Buy D-Aspartic Acid
- DAA Pure Review
- N-Methyl-D-Aspartic Acid
D-aspartic acid (DAA) is an enantiomer of aspartic acid. Enantiomers are molecules that share the same chemical composition, but structurally are mirror images of one another.
In the case of aspartic acid, there are two enantiomers – L and D – that play different roles in the body. D- and L-aspartic acid can also be differentiated because they bend light in different directions.
Aspartic acid is a non-essential amino acid, which means it is naturally produced by the body and does not need to be consumed in food to maintain healthy levels. This is as opposed to essential amino acids that cannot be synthesized by the body and must be ingested for survival.
However, some individuals choose to take DAA to support improved testosterone levels and as part of a bodybuilding supplementation plan. DAA has been observed to start a biochemical cascade that is associated with testosterone production.
DAA supplements were not introduced to the American marketplace until the mid-1990s. The majority of studies available on DAA focus on its natural role in the body and not on the effects of supplementation.
D-Aspartic Acid and Testosterone Effects
Supplementation with DAA may be helpful for improving low testosterone levels. When a man is affected by low testosterone levels, he may experience any or all of the following:
- Low sex drive (libido);
- Decreased muscle mass and strength;
- Irritability and/or depression;
- Symptoms of erectile dysfunction, including premature ejaculation, inability to get and maintain erections and poor sexual performance levels;
- Androgenic alopecia (hair loss);
- Inability to focus;
- Increased triglyceride levels (stored fats);
- Low self-worth.
There are several methods of testosterone replacement therapy available. Transdermal skin patches, topical gels, mouth patches, implants and injections are used by hundreds of thousands of males every day.
These testosterone replacements options come with a set of possible side effects including, but not limited to:
- Liver damage;
- Enlarged prostate;
- Gynecomastia (male breast development);
- Priapism (non-ending, painful erections);
- Acne and/or rashes;
- Baldness.
Testosterone plays a number of important functions in the body. DAA supplementation has been observed to increase testosterone synthesis in the testicles, which may support increased muscle size and strength, increased athletic/sexual endurance, improved fat metabolism, more restful sleep, increased sex drive, better moods and elevated energy levels.
It is unclear whether DAA will also cause side effects similar to those of Testosterone Replacement Therapies. More research and comparative studies are needed.
D-Aspartic Acid Side Effects
When DAA is taken in doses of less than four grams per day, there are very few side effects that have been reported.
DAA is a natural amino acid that plays a number of integral roles in human health and well being.
It is generally very well tolerated by humans. In rare cases, the following side effects have been observed with DAA supplementation:
- Acne;
- Nausea and/or vomiting;
- Irritability, depression and/or mood changes;
- Diarrhea;
- Headache.
Speak to your doctor to determine whether this supplement is appropriate for you. While there have not been any drug or supplement interactions noted in the literature, it is possible that this supplement may be contraindicated for some people.
Side effects of excess use of D-Aspartic Acid may be similar to those of other testosterone-boosting agents.
Research into D-Aspartic Acid Supplementation
Clinical research into DAA is limited. While there have been promising preliminary results, more research is needed to attribute DAA with any particular therapeutic benefits.
The following are some observations that have been reported from DAA studies:
- Sperm quantity, quality and motility have been observed to increase significantly in infertile men supplementing with DAA over a 90-day period.
- Baseline sperm motility rates were observed to increase between 50 and 100 percent after 90-day DAA supplementation in men with oligoasthenozoospermia and asthenozoospermia.
- 12-day supplementation with D-aspartic acid was observed to cause a 33 percent increase in LH (luteinizing hormone) and a 42 percent increase in free testosterone.
- 14-day supplementation of DAA in rats was correlated with memory improvements;
- DAA was observed to enhance postsynaptic secondary neurotransmission.
- DAA has been observed to stimulate improved hippocampal performance in studies on rats.
- DAA build-up in the anterior pituitary gland has been associated with increases in gonadotropin releasing hormone (GnRH), which increases LH (luteinizing hormone), which leads to testosterone production.
- DAA supplementation has been observed to increase follicle stimulating hormone (FSH), human growth hormone (hGH) and prolactin.
- D-aspartic acid concentration is highest in the pineal gland.
- DAA suppresses the excessive synthesis of melatonin, which controls sleep/wake cycles.
- D-aspartic acid increases the synthesis of messenger RNA that generates the StAR (stimulating steroidogenic acute regulatory) protein, which increases testosterone production.
There are few known side effects associated with DAA supplementation, but long-term studies are lacking. Similarly, there are no known drug contraindications. Please consult with your doctor before you start taking this supplement to avoid D-aspartic acid side effects.
- Melville GW, Siegler JC, Marshall PWM. Three and six grams supplementation of D-aspartic acid in resistance trained men. J Int Soc Sports Nutr. 2015; 12: 15.
- D'Aniello A, Di Cosmo A, Di Cristo C, Annunziato L, Petrucelli L, Fisher G. Involvement of D-aspartic acid in the synthesis of testosterone in rat testes. Life Sci. 1996;59(2):97-104.
- Ota N, Ting S, and Sweedler JV. D-aspartate acts as a signaling molecule in nervous and neuroendocrine systems. Amino Acids 43.5 (2012): 1873–1886.
Article last updated on: March 31st, 2018 by Nootriment