Table of ContentsView AllTable of ContentsWhat Is D-Aspartic Acid?UsesDosageSafetySimilar SupplementsFrequently Asked Questions
Table of ContentsView All
View All
Table of Contents
What Is D-Aspartic Acid?
Uses
Dosage
Safety
Similar Supplements
Frequently Asked Questions
D-aspartic acid (D-asp) is an amino acid that is important for both the endocrine system and the central nervous system (the brain and spinal cord). Studies have indicated that it boosts testosterone levels, improves fertility, and reduces symptoms of schizophrenia, but more research is needed.
D-asp may function as aneurotransmitter, a chemical messenger that transmits signals between nerves and other cells, though scientists debate this role.It’s made in the body and found in certain foods—like spinach, beets, and strawberries—as well as supplements.
In the United States, the Food and Drug Administration (FDA) does not regulate supplements the way it regulates prescription drugs. That means some supplement products may not contain what the label says. Whenchoosing a supplement, look for independently tested products and consult a healthcare provider, registered dietitian nutritionist (RD or RDN), or pharmacist.
Taking a break from exercise with a protein shake.Luza Studios / Getty Images
Luza Studios / Getty Images
D-aspartic acid binds toN-methyl-D-aspartate receptors (NMDARs)in the brain and helps control neuroplasticity and brain activity.It also helps regulate hormones like:
D-asp is made in the body. Levels in the brain are highest before birth, while levels in the endocrine glands increase after birth.It’s also found in the following foods:
D-aspartic acid is also available as a dietary supplement in capsule and powder form.
It has been studied for conditions likeschizophrenia,Alzheimer’s disease,autism, and hormone-related issues likefertility.
D-Aspartic Acid Supplement FactsActive ingredients:Aspartic acidAlternate names:D-aspartate, aminosuccinic acidLegal status:Over-the-counter (OTC) supplement in the U.S.Suggested dose:3–6 grams a day for up to three months has been studied in clinical trialsSafety concerns:hasn’t been studied in pregnancy, lactation, children, older adults, or those with chronic conditions
D-Aspartic Acid Supplement Facts
Active ingredients:Aspartic acidAlternate names:D-aspartate, aminosuccinic acidLegal status:Over-the-counter (OTC) supplement in the U.S.Suggested dose:3–6 grams a day for up to three months has been studied in clinical trialsSafety concerns:hasn’t been studied in pregnancy, lactation, children, older adults, or those with chronic conditions
Although D-aspartic acid is commonly promoted as anergogenic aidto increase exercise performance, it has not been studied much in humans for this or any other condition.
Here’s what the latest research suggests about the potential benefits of D-asp.
Boosting Testosterone Levels
D-asp has been shown toincrease testosterone levelsin some populations, though the evidence is inconsistent.
A systematic review concluded that D-aspartic acid supplements may only increase testosterone in males with low baseline levels.
Discusstestosterone replacement therapyor other supplements that may increase your testosterone levels with your healthcare provider if you have low levels and problematicsymptoms.
Fertility
D-asp may improvefertility, but more data is necessary.
A product containing D-asp plusfolic acidand vitamins B6 andB12nearly doubled sperm concentration and mobility in a small study of 60 males.This resulted in a higher pregnancy rate for the partners of those who used the combination product.
Although D-asp hasn’t been well studied for female fertility, higher levels in theovarieswere associated with younger age and high egg quality.
More robust clinical trials are necessary before D-aspartic acid can be routinely recommended for fertility. Discuss treatment options with your healthcare provider if this concerns you.
Schizophrenia
Early research suggests that D-aspartic acid helped reduce symptoms in people with treatment-resistantschizophrenia.
It’s been studied in mice models, which showed that those with high levels of D-asp had increased brain connectivity and spatial memory.Very small studies—up to 20 people—showed that D-asp levels were 30% lower in the brains of people with schizophrenia than those without.
Clinical trials in humans are necessary to confirm these effects.
Keep in mind that mental health conditions like schizophrenia should not be self-treated. If not appropriately managed, quality of life and functioning could decline.
D-aspartic acid has been studied in clinical trials at doses of 3–6 grams per day for fertility and testosterone enhancement.
Avoid D-aspartic acid if you’re allergic to it or its components (parts).
Seek immediate medical attention if you have asevere allergic reaction(itching, hives, shortness of breath, etc.).
Side Effects
In general, very little safety data is available for amino acid supplements like D-aspartic acid.This means not enough is known about these supplements' safety, particularly at high doses or with long-term use.
Increased amounts of any amino acid can cause an imbalance in other amino acid concentrations in the body, including lower levels of these other amino acids.
D-aspartic acid may cause the following side effects, according to a clinical trial:
Interactions
Because D-aspartic acid may alter levels of testosterone andestrogen,it can interact with other medications that affect these hormones. A few common examples of medicines that affect hormone levels include:
Precautions
D-aspartic acid supplements may be riskier for some than others. Keep the following precautions in mind when deciding if D-aspartic acid is suitable for you.
There’s not enough safety data to recommend D-asp for people with chronic conditions or those who are:
To optimize safety, consult your healthcare provider, pharmacist, or registered dietitian before taking dietary supplements.
Many dietary supplements are marketed as testosterone boosters, though for some, there is very little evidence to support these claims. Some supplements people take to increase testosterone levels include the following:
Before taking supplements toboost testosterone, discuss your goals with your healthcare provider so they can tailor your treatment plan to you.
Some supplements that may help symptoms of schizophrenia include the following:
Note that these supplements do not replace first-line therapy with antipsychotics.There’s not enough evidence to recommend them unless a healthcare provider who can monitor your condition is following you closely.
Summary
D-aspartic acid is an amino acid that is made in the body and obtained through the diet. It’s important for brain function and the endocrine system.
It’s often marketed as a testosterone booster or performance enhancer in supplement form.
Though D-aspartic acid may benefit fertility or schizophrenia, it’s too soon to know. There’s little evidence that this supplement increases testosterone, strength, fertility, or mental health for now.
Frequently Asked QuestionsD-aspartic acid is an amino acid that is involved in brain development and hormone regulation.D-aspartic acid is important for nerve signaling and the release of hormones like testosterone, prolactin, and oxytocin. It’s a crucial part of the reproductive process of mammals, though its effects in humans are less studied.D-aspartic acid supplements may improve fertilityor decrease symptoms of schizophrenia,but more clinical trials in humans are necessary to know for sure.We don’t know for sure because there are very limited clinical trials, and most don’t report side effects. More research is necessary to understand the safety of D-aspartic acid.
D-aspartic acid is an amino acid that is involved in brain development and hormone regulation.
D-aspartic acid is important for nerve signaling and the release of hormones like testosterone, prolactin, and oxytocin. It’s a crucial part of the reproductive process of mammals, though its effects in humans are less studied.D-aspartic acid supplements may improve fertilityor decrease symptoms of schizophrenia,but more clinical trials in humans are necessary to know for sure.
D-aspartic acid is important for nerve signaling and the release of hormones like testosterone, prolactin, and oxytocin. It’s a crucial part of the reproductive process of mammals, though its effects in humans are less studied.
D-aspartic acid supplements may improve fertilityor decrease symptoms of schizophrenia,but more clinical trials in humans are necessary to know for sure.
We don’t know for sure because there are very limited clinical trials, and most don’t report side effects. More research is necessary to understand the safety of D-aspartic acid.
23 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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