The hormone testosterone is well-known for its role in building muscle and influencing sex drive. For this reason, men of all ages seek natural methods for increasing their levels of this powerful hormone.
The use of natural supplements that increase testosterone levels is one of the most popular ways men attempt to achieve this. These supplements often contain the ingredient D-aspartic Acid.
This article will cover what D-aspartic Acid is and how it affects testosterone.
What is D-Aspartic Acid and How Does It Work?
Amino acids can be described as molecules having multiple important functions in the body. They are essential for building all forms of protein as well as specific neurotransmitters and hormones.
Nearly every amino acid can be identified as having two different forms. Therefore, aspartic acid occurs as both D-aspartic acids and L-aspartic acid.
Although they share the same chemical composition, their molecular structures mirror one another. This is why the D- and L- forms of an amino acids are often referred to as “right-” or “left-handed”.
L-aspartic acid is found in nature and also in the human body. While L-aspartic acid is used to make proteins, D-aspartic acid is not. Rather, it performs an important function in hormone production in the body.
D-aspartic Acid is able to increase the production of luteinizing hormone (LH) in the brain, which directly influences testosterone production. It is also involved in raising testosterone production and secretion in the testes.
Because of the role that D-aspartic acid plays in testosterone production, it is a popular ingredient in many testosterone-boosting supplements.
How D-Aspartic Acid Affects Testosterone Levels
The results of clinical studies have so far been mixed when it comes to possible effects that D-aspartic acid has on testosterone levels. While some research has shown that D-aspartic does increase testosterone levels, but other research does not support this.
Research involving otherwise healthy men between the ages of 27 and 37 looked into the effects of D-aspartic acid supplementation over a 12-day period. The study found that out of the 23 men who took D-aspartic acid, 20 had a 42% average increase in testosterone levels by the end of the study. (1)
The average testosterone level of the participants was still 22% higher three days after having stopped taking the supplement.
Another research study involving obese and overweight men found mixed results. After taking D-aspartic acid for 28 days, some of the men experienced no increase in testosterone, but men who had lower testosterone levels at the start of the study saw increases of more than 20%. (2)
Other research involving men between the ages of 27 and 43 looked at the effects of supplementation for periods of greater than one month. Researchers observed a 30% to 60% increase in testosterone in the men who took D-aspartic acids for 90 days. (3)
While these studies didn’t specifically include subjects who were physically active, three other studies did look into effects that D-aspartic acid had on active men. One study observed that testosterone levels did not increase in young men who practiced weight training exercises and used D-aspartic for a 28-day period. (4)
Interestingly, another study showed that a high dose of D-aspartic acid at 6g per day actually reduced testosterone in young who performed weight training. (5) Additionally, a follow up study of men using 6 grams of DAA per day over a three-month period revealed no changes in testosterone levels. (6)
Similar studies involving women are not available at the moment, possibly because some of D-aspartic acid’s effects are specific to the testes.
See Also: The Best Testosterone-Boosting Supplements Ranked
Bottom Line
D-aspartic acid could raise testosterone levels in men with low testosterone or who are inactive. It has not, however, been proven to increase testosterone in men who lift weights or are otherwise physically active.
References:
- https://rbej.biomedcentral.com/articles/10.1186/1477-7827-7-120
- https://benthamopen.com/ABSTRACT/TONUTRAJ-8-43
- https://www.scirp.org/journal/paperinformation.aspx?paperid=24016
- https://www.sciencedirect.com/science/article/abs/pii/S0271531713001735?via%3Dihub
- https://www.tandfonline.com/doi/full/10.1186/s12970-015-0078-7
- https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0182630
