L-serine is an amino acid that plays a role in the function of the nervous system, including the brain. It’s a nonessential amino acid, meaning it is produced within the body. However, the body doesn’t produce enough l-serine on its own, so it’s important to get enough via diet or supplementation.1Phosphoserine Aminotransferase Deficiency: A Novel Disorder of the Serine Biosynthesis Pathway
In this guide:
| Quick Glance | ||
 | Best Powder: Micro-Ingredients – Pure L-Serine Powder (500 g) “This is pure l-serine powder, with no fillers or artificial ingredients.” | Check Price |
 | Best Capsules: Douglas Laboratories – L-Serine Capsules “These capsules contain 100% pure l-serine powder.” | Check Price |
 | Best Value: BulkSupplements – L-Serine Powder (1000 g) “Per serving, this is one of the most inexpensive l-serine supplements available.” | Check Price |
Top 3 L-Serine Supplements
Best L-Lysine Powder
Micro Ingredients – Pure L-Serine Powder (500 g)
This is the go-to l-serine supplement. It’s pure l-serine powder, with no fillers or artificial ingredients. In addition, Micro Ingredients guarantees that the their l-serine powder is free of gluten, soy, and GMOs.
Best L-Lysine Capsules
Douglas Laboratories – L-Serine Capsules
60 capsules | 500mg per capsule |
Not everyone likes to take powders directly. These l-serine capsules are a great alternative. They contain 100% pure l-serine powder, each with a 500-milligram dose.
Best Value L-Lysine Supplement
BulkSupplements – L-Serine Powder (1000 g)
BulkSupplements is the king of inexpensive health products, and their l-serine supplement powder is no different. Per serving, this is one of the most inexpensive l-serine supplements available.
L-Serine Benefits
More research on l-serine is needed, but there have been some interesting findings on this amino acid thus far.
Research has found a correlation between low levels of l-serine and decreased cognitive function.2l-Serine synthesis in the central nervous system: A review on serine deficiency disorders These low-l-serine deficits can include the following:3An update on serine deficiency disorders4Treatment with amino acids in serine deficiency disorders5Continuing Education in Neurometabolic Disorders – Serine Deficiency Disorders6l-Serine in disease and development
Effects of Low L-Serine Levels
- Decreased psychomotor skills (i.e., hand-eye coordination, dexterity, fine manipulation, etc.)
- Increased risk of seizures
- Polyneuropathy (nerve damage resulting in numbness, weakness, and/or pain)
- Psychiatric disorders
L-serine is required to produce compounds vital to proper brain function, including certain phospholipids and neurotransmitters.7Serine-deficiency syndromes Neurotransmitters are chemicals involved in relaying signals among nerve and muscle fibers. Phospholipids, a component of cell membranes, sometimes play a similar role.
L-Serine vs. D-Serine
Research has shown that d-serine may help support the brain and nervous system, as discussed below. But what’s the difference between l-serine and d-serine?
L-serine is converted into d-serine in glial cells surrounding neurons. However, taking d-serine directly as a supplement may not be safe. It is not classified as a Generally Regarded as Safe substance by the FDA, while l-serine is. Research on supplementing d-serine directly is limited.
Taking all of this into account, most people looking to supplement serine will opt for l-serine, since it’s converted to d-serine anyway and is regarded as safe to supplement.
Benefits of L-Serine’s Byproduct: D-Serine
Studies have identified a handful of potential effects and benefits of d-serine, the product of l-serine.
- Potential Memory Improvement
Research has shown that increased d-serine levels may support mechanisms associated with memory.8Long-term potentiation depends on release of D-serine from astrocytes
- Potential Neuron Signaling Improvement
Research has demonstrated that d-serine plays a vital role in supporting certain neurotransmitters.9Glia-Derived d-Serine Controls NMDA Receptor Activity and Synaptic Memory In turn, neurotransmitters play a role in transmitting signals throughout the body’s nervous system, including the brain.
- Potential Impact on Schizophrenia Symptoms
Several studies found that supplementing d-serine reduced symptoms of schizophrenia in most subjects.10D-serine added to antipsychotics for the treatment of schizophrenia11D-serine efficacy as add-on pharmacotherapy to risperidone and olanzapine for treatment-refractory schizophrenia12High dose D-serine in the treatment of schizophrenia It’s very important to note that d-serine was taken alongside the patients’ usual anti-psychotic medication. A regimen of d-serine alone against schizophrenia symptoms has not been studied.
L-Serine and Alzheimer’s Disease
The little research that has been performed on l-serine and Alzheimer’s disease thus far is unclear and conflicting.
One study found that levels of d-serine (a product of l-serine) were higher in patients with Alzheimer’s disease than in control subjects.13D-serine levels in Alzheimer’s disease: implications for novel biomarker development Another study found that levels of d-serine were lower in patients with Alzheimer’s disease.14Possible role of d-serine in the pathophysiology of Alzheimer’s disease The same study found that l-serine levels were higher in Alzheimer’s disease patients.
As it currently stands, research does not support l-serine supplementation as a means to impact Alzheimer’s disease symptoms.
L-Serine Dosage
There is currently no official recommended l-serine dosage. However, several studies have found that an l-serine dosage of up to 400 milligrams per kilogram of bodyweight per day is likely safe.15Clinical and metabolic consequences of L-serine supplementation in hereditary sensory and autonomic neuropathy type 1C16L-Serine Supplementation in Hereditary Sensory Neuropathy Type 1
L-serine dosages can be broken up throughout the day or taken all at once. There is no research to suggest timing of an l-serine dosage is important. They can be taken either with or in between meals.
L-Serine Side Effects
At an l-serine dosage of up to 400 milligrams per kilogram of bodyweight per day, studies have not noted any significant side effects. Some individual users have reported upset stomach and/or diarrhea, but this has not been widely found in studies.
Summary
L-Serine supplements may be considered as a way to support brain and nervous system function. However, while the current data is promising, more research on this amino acid is needed.
There are more thoroughly-studied supplements that have been shown to support cognitive health and performance, such ashwagandha and rhodiola. These may be better alternatives for some people.
| Best L-Serine Supplements Overview | ||
| | Best Powder: Micro-Ingredients – Pure L-Serine Powder (500 g) “This is pure l-serine powder, with no fillers or artificial ingredients.” | Check Price |
| | Best Capsules: Douglas Laboratories – L-Serine Capsules “These capsules contain 100% pure l-serine powder.” | Check Price |
| | Best Value: BulkSupplements – L-Serine Powder (1000 g) “Per serving, this is one of the most inexpensive l-serine supplements available.” | Check Price |