D-Aspartic Acid: How It Works, Benefits, Clinical Studies And Side Effects

D-Aspartic Acid

What is D-Aspartic Acid?

D-Aspartic Acid

It is an alpha-amino acid which is required by the body in building proteins, predominantly found in the testes and pituitary gland.

Function: It regulates the synthesis of the male hormone, testosterone, and can be effective for male infertility. Used as test booster by the supplement manufacturing companies.

Similar test boosting herbs: Tribulus terrestris, Fenugreek, Nettle leaf, Panax Ginseng, etc.

It is a non-essential amino acid which is eminent for playing a major role in the synthesis of testosterone by its regulation. It collects in the testes and plays an important role in the biosynthesis of sex hormones, especially testosterone in the body. The D-Aspartic acid supplements continue to produce testosterone even after stopping its use.

Benefits of D-Aspartic Acid as a Testosterone Booster

D-Aspartic acid has the following effects as a testosterone booster:

  • It regulates and stimulates the release of testosterone in the body
  • The synthesis of testosterone continues for some time even after stopping the use of the supplement
  • D-Aspartic acid accumulates in the testes and continues to produce testosterone in the absence of the supplement
  • It is more effective and efficient than L-Aspartate in increasing testosterone
  • It can treat male infertility
  • Increased libido
  • Increased sperm count

By increasing testosterone levels in the body, D-Aspartic acid can have the following effects for bodybuilding:

  • Increased muscle strength
  • Increased muscle mass
  • Increased exercise endurance
  • Improved physical performance
  • Increased energy

How Does It Work?

D-AA is mainly found in the brain (where it works as neurotransmitter) and in the testes. It is present in abundance in the leydig cells of the testes, where it also serves as a signalling molecule. It receives signals from the pituitary gland and then stimulates the leydig cells to form testosterone from cholesterol.

Other Benefits

Some other benefits of D-Aspartic acid are as follows:

  • Improves brain function
  • Helps in memory and learning
  • It may play an important part in neurotransmission
  • It may have a significant impact on sight
  • It works as a neuromodulator
  • It helps in the release of certain hormones such as LH (luteinizing hormone), growth hormone and follicle stimulating hormone
  • It works as a signalling molecule

D-Aspartic Acid SourceSources

It is found in many fruits and vegetables such as avocados, oysters, asparagus, sprouts, molasses and meat. For body building and increasing testosterone levels, it is wise to take D-Aspartic acid supplements as they have been proven to be effective for both.

Clinical Studies

In a study, 23 men were given D-Aspartate for a period of 12 days, while another group of 20 men received a placebo. Meanwhile, an animal study was also carried out on rats. Two groups of 10 rats were either given a solution of D-Aspartic acid, or a placebo for 12 days.

At the end of the study, it was found that D-Aspartic acid plays a role in pituitary gland and testes in the synthesis and regulation of testosterone (both in humans and rats).


D-Aspartic acid may be taken in the range of 2-5gm per day. If you are working out to build muscle, it is recommended to take the supplement an hour or 30 minutes before workout.

Side Effects

There are no serious side effects of D-Aspartic acid, but some people may experience the following side effects of D-Aspartic acid:

  • Enhanced libido
  • Increased appetite
  • Increased hair growth
  • Acne
  • Enhanced levels of aggression
  • Headaches
  • Mood swings
  • Diarrhoea


D-Aspartic acid is commonly present in the pituitary gland and testes where it works as a neurotransmitter and signalling molecule. For men with low testosterone, such as older men, D-Aspartic acid serves as a remedy by boosting testosterone. It stimulates the production of testosterone in the leydig cells of the testes, when signalled by the pituitary gland. By increasing testosterone, D-Aspartic acid has also become a popular supplement among men who are aiming to build muscle and increase their muscular strength. Before starting on D-Aspartic acid as a supplement, either as a treatment or for enhancing your workout sessions, you must consult with your doctor to ensure your health safety. Although, there are no serious side effects of D-Aspartic acid, but refrain from exceeding the recommended dosage as certain health implications might occur as a consequence.