Myelin is an important part of the nervous system and is vital for optimal cognitive function. Read on to learn more about its purpose and find out which factors may increase myelin in the body.
What Is the Myelin Sheath?
Definition & Facts
The myelin sheath is a cover made out of fats and proteins that wraps around the axons (projection) of nerve cells. It insulates neurons so they can send electrical signals faster and more efficiently. This supports brain health and nervous system function [1, 2].
Here are some quick facts about myelin:
- About 80% fats/cholesterol and 20% proteins.
- Considered an outgrowth or extension of a type of glial cell (oligodendrocyte – CNS, Schwann cell – PNS).
- Continues to grow throughout adolescence and even into our early 20s.
- Myelinated axons are white in appearance, hence the term “white matter” of the brain.
Myelin improves the conduction of action potentials, which are needed to send information down the axon to other neurons .
The myelin sheath increases the speed of impulses in neurons. It facilitates conduction in nerves while saving space and energy .
Myelin helps prevent the electrical current from leaving the axon. It allows for larger body sizes by maintaining efficient communication at long distances.
When babies are born, many of their nerves lack mature myelin sheaths. As a result, their movements are jerky, uncoordinated, and awkward. Scientists think that, as myelin sheaths develop, movements become smoother, more purposeful, and more coordinated [4, 5].
Research suggests that myelination might improve children’s cognitive performance improves as they grow and develop .
Additionally, when a peripheral fiber is severed, the myelin sheath provides a track along which regrowth can occur .
When Does Myelination Stop?
Researchers think that myelination occurs most significantly during childhood, but some brain imaging studies suggest it may continue until 55 years of age and possibly even throughout life .
Oligodendrocytes vs. Schwann Cells
Oligodendrocytes and Schwann cells are types of cells that produce, maintain, and repair myelin .
Schwann cells normally produce myelin in peripheral nerves (outside the brain), but can enter the brain when needed .
On the other hand, oligodendrocytes are found solely in the brain. They are responsible for the formation of new myelin in both the injured and healthy adult brains .
Symptoms and Conditions Linked With Myelin Loss or Damage
Demyelination refers to myelin damage or loss. It disrupts signals between neurons and may result in a diverse range of neurological symptoms. These depend on whether peripheral (outside the brain) or central (in the brain and spinal cord) neurons are affected, and to what extent .
Symptoms differ from patient to patient and have different presentations, depending on the specific demyelinating disorder. The most common demyelinating disorder affecting the central nervous system is Multiple Sclerosis .
Thus, symptoms shown here are commonly associated with demyelinating disorders. This list is not exhaustive. The most important step is to see your doctor or other health care professional to get an accurate diagnosis and treatment .
- Blurred vision that may affect only one eye
- Double vision
- Loss of vision/hearing
- Odd sensation in legs, arms, chest, or face, such as tingling or numbness (neuropathy)
- Muscle weakness
- Cognitive dysfunction, including speech impairment and memory loss
- Heat sensitivity
- Loss of dexterity
- Difficulty coordinating movement and/or balance
- Difficulty controlling bowel movements and/or urination
Multiple sclerosis is the most common demyelinating disorder. The cause of multiple sclerosis is unknown, though many contributing factors have been proposed .
- Acute disseminated encephalomyelitis
- Acute hemorrhagic leukoencephalitis
- Neuromyelitis optica
- Chronic inflammatory demyelinating polyneuropathy
- Central pontine myelinosis
- Inherited demyelinating diseases such as leukodystrophy
- Charcot-Marie-Tooth disease
- Adrenoleukodystrophy and adrenomyeloneuropathy
- Leber hereditary optic neuropathy
- Progressive multifocal leukoencephalopathy
The exact cause of many demyelinating disorders is often an enigma. Science suggests that certain primary demyelinating disorders develop after a viral infection or vaccination against viral infection .
Some researchers hypothesize that this might be because a virus or another substance somehow triggers the immune system to attack the body’s own tissues (autoimmune reaction). The autoimmune reaction results in inflammation, which damages the myelin sheath and the nerve fiber under it [10, 12].
HIV infection can also cause white matter abnormalities, including myelin damage .
Genetic Myelin Sheath Disorders
- Tay-Sachs disease
- Niemann-Pick disease
- Gaucher disease
- Hurler syndrome
- Canavan disease
- Charcot-Marie-Tooth disease
- Krabbe’s leukodystrophy
Other Poorly-Researched Associations
Aside from demyelinating disorders, limited studies have linked the following disorders to white matter or myelin loss or damage:
- PTSD 
- ADHD 
- Depression 
- Chronic Fatigue Syndrome 
- Schizophrenia 
- Mild cognitive impairment in Alzheimer’s disease 
- Traumatic brain injury 
- Tourette’s syndrome 
- Tone deafness 
- Pathological lying 
- Guillain-Barré syndrome 
- Diabetes 
- Nutritional deficiencies (such as B12 deficiency) 
- Poisoning with lead, carbon monoxide, or deadly plants like rosary pea [23, 24, 25]
- Drugs (such as the antibiotic ethambutol used to treat tuberculosis) 
According to some theories, reduced white matter in the brain is a contributing factor to some brain-related conditions. Also, scientists think that certain conditions are caused by white matter reductions. At other times, science suggests that specific conditions themselves may cause white matter reduction .
However, many of these links are purely investigational and lack large-scale human data as support.
Additionally, the majority of studies that focused on these conditions dealt with associations only, which means that a cause-and-effect relationship hasn’t been established.
For example, just because depression has been linked with altered white matter (made up of myelin) in certain brain areas doesn’t mean that depression is caused by myelin damage. Data are lacking to make such claims.
Also, even if a study did find that poor myelination contributes to depression, myelin is highly unlikely to be the only causative factor. Complex disorders like depression always involve multiple possible factors – including brain chemistry, environment, health status, and genetics – that may vary from one person to another.
Therefore, more research is needed to determine the association between these disorders and myelin or white matter abnormalities.
What Happens to Myelin in Multiple Sclerosis?
Multiple sclerosis is an autoimmune condition in which the person’s immune system attacks the myelin sheath or cells that maintain it .
As myelin continues to degrade, symptoms such as impaired balance, and cognition may arise .
Cognitive impairment occurs in 40 to 65% of multiple sclerosis patients. The deficits are typically in complex attention, information processing speed, (episodic) memory, and executive functions .
Myelin & Intelligence
Do We Have a Clear Link?
Since science discovered that myelin works as a sort of a fine cable for the brain – helping carry electrical signals between neurons at high speeds – some have suggested that it may play a critical role in determining intelligence .
Since myelin allows signals to travel faster, researchers think it might make the brain as a whole work better. We know that white matter – nerve fibers coated with myelin – support normal cognitive function, learning, and IQ. But the specifics of the “myelin intelligence” theory have yet to be determined in humans [8, 32].
It’s important to know that studies attempting to find links between brain factors like myelin and intelligence are bound to have inconsistencies and flaws. Intelligence is a complex trait and most studies can only point to possible links. But many factors interact to shape its various aspects: general, verbal, mathematical, emotional, and other types of intelligence 
Myelin controls the speed of impulse conduction through axons, and the synchrony of impulse traffic between distant brain regions seems to be critical for optimal mental performance and learning .
Limited studies suggest that myelination of appropriate brain regions coincides with the development of specific cognitive functions, such as reading, development of vocabulary, and proficiency in executive decision making .
Incomplete myelination of the forebrain until the early twenties has been suggested as a neurological basis for weaker decision-making skills in adolescence, though this association remains controversial .
Small studies have suggested a correlation between individual differences in normal cognitive development, IQ, reading skills, working memory, and musical proficiency with differences in white matter in specific brain regions mediating these tasks. Future large-scale studies are needed to clarify this link .
In another small study, white matter levels in certain regions were also associated with arithmetic ability, reaction time, and cognitive control .
Learning complex skills, such as playing the piano, appear to be accompanied by increased white matter in brain areas involved in musical performance. White matter increased proportionately to the number of hours each subject had practiced the instrument, indicating white matter increases when acquiring certain skills .
However, such studies have limitations that make it difficult to determine whether learning a new skill can directly impact myelination.
A couple of studies have noted a positive correlation between white matter volume and intelligence at the level of whole brain white matter volume as well as in specific white matter regions .
Additionally, researchers suggest that prefrontal white matter volume is disproportionately larger in humans compared to non-human primates .
To sum it up, white matter and myelin have been associated with the following aspects of intelligence in limited, small studies :
- Working memory
- Verbal ability
- Reaction time
- Cognitive control
- Musical ability
- Arithmetic capacities
However, larger and better-designed studies are needed before we can draw any clear conclusions.
Factors that May Increase Myelination
When to see a doctor
If your goal is to increase myelin to improve your neurological issues–including those of cognitive dysfunction – it’s important to talk to your doctor, especially your symptoms are significantly impacting your daily life.
Your doctor should diagnose and treat the condition causing your symptoms.
Additionally, brain structure is not something that people can change on their own with the approaches listed below. Instead, the factors listed here are meant to support overall brain health, nutrient balance, and well-being.
However, the impact of most of the factors listed below on myelination have not been studied in humans.
Therefore, you may try the additional strategies listed below if you and your doctor determine that they could be appropriate.
Read through the approaches listed here and discuss them with your doctor before trying them out. None of these strategies should ever be done in place of what your doctor recommends or prescribes.
Animal studies suggest that sleep increases the amount of oligodendrocyte precursor cells (OPCs) in the body, which can lead to increased myelin formation. Sleep has been associated with higher expression of genes coding for myelination .
Researchers found that the production rate of the myelin-making cells (oligodendrocytes), doubled as mice slept .
The increase was most marked during the type of sleep that is associated with dreaming (REM sleep) .
In contrast, the genes involved in cell death and stress responses were turned on when the mice were forced to stay awake .
Getting enough restful sleep is good for overall brain health and well-being. Human studies are needed to examine the effects of sleep on myelination.
Exercise also seems to increase mitochondrial function, which increases myelin, in animals fed a high-fat diet .
We still don’t know how exercise impacts myelin in humans, but we do know that regular exercise supports brain health .
3) Socializing and New Experiences
Limited research suggests that socializing and enriched environments may support myelination, especially during early development.
The number of myelin-forming oligodendrocytes increased 27 to 33% in the visual cortex of rats raised in environments that are enriched by additional play objects and social interaction .
Enriched environments increased the number of myelinated axons in the corpus callosum of monkeys and rats .
Early experience increased white matter structure in human infants (internal capsule and frontal lobes) in parallel with improved performance in behavioral tests .
Children suffering from severe childhood neglect have a 17% reduction in the corpus callosum area .
4) Learning New Complex Skills
White matter increased proportionately to the number of hours each subject had practiced the instrument, indicating white matter increases when acquiring certain skills .
1) Fish/DHA (Brain)
DHA is deposited within the cerebral cortex at an accelerated rate during the last trimester of pregnancy and during the first 2 years after birth .
Researchers think this might be due, in part, to negative impacts on neurite outgrowth and myelination .
More clinical data are needed.
2) Vitamin D
Maintaining normal vitamin D levels supports bone health and immunity. Animal studies show that vitamin D3 may induce functional recovery and increased myelination in a rat model of facial nerve injury. Scientists are researching whether the vitamin D receptor can increase the production of oligodendrocytes. Human studies are required [50, 51].
3) Vitamin C
Vitamin C, also known as ascorbate, is important as a cofactor in several enzyme reactions. Scientists suspect that ascorbate-dependent collagen synthesis may help with myelination. Ascorbate added to rat Schwann cells and neurons promoted myelin formation .
Human studies are lacking.
Iodine is essential for many bodily functions. Animal research suggests that iodine deficiency may impair myelination. Supplementation with iodine helps improve myelin formation in nerve cells, but no clinical data back up this finding .
6) Choline and Lecithin
In animal models of multiple sclerosis, the choline pathway seems to help with remyelination of myelin sheaths. It enhances myelin repair. This pathway hasn’t been investigated in people with MS .
CDP-choline improved myelination in animal models of multiple sclerosis .
After drug-induced demyelination, CDP-choline enhanced myelin regeneration and reversed motor coordination deficits .
The increased remyelination arose from an increase in the numbers of proliferating oligodendrocytes and oligodendrocyte precursor cells .
Lecithin is a component of myelin .
The effects of these compounds on myelination in humans have yet to be researched.
7) Vitamin B12
Iron plays a key role in proper cell function. Some studies suggest that normal iron levels are needed for myelin formation. Iron deficiency has been linked with poor myelination. Therefore, iron may support myelination in the body (oligodendrocytes), but more human data are needed .
9) Vitamin K
Myelin membranes are particularly enriched with glycolipids, including galactosylceramide (GalCer) and its sulfated form, sulfatide .
Animal findings suggest that concentrations of sulfatides increase during brain development, parallel to an increase in brain myelination .
Decreases in myelin sulfatides content and/or changes in their molecule structure have been implicated as important factors in the disruption of myelin structure, with subsequent attenuation of myelin efficiency as an axonal insulator .
Decreases in the content of myelin sulfatides with age have been implicated in behavioral deficits observed in normal aging, and age-associated neurological disorders. However, no large-scale human studies have confirmed this link .
Theoretically, getting adequate amounts of vitamin K may support myelination. Vitamin K has been implicated in increasing sulfatides; a link between sulfatides and vitamin K has been suggested. In the brain, vitamin K is mostly found as vitamin K2 or menaquinone-4 (MK-4) .
Human data are needed.
Some scientists consider that biotin activates enzymes involved in energy production and myelin synthesis .
Two multi-centric double-blind placebo-controlled trials are currently underway. We have yet to see if their results will support the use of biotin in MS or not .
11) Folate/Vitamin B9 (Brain)
Folate deficiency during pregnancy caused lower myelination in rat offspring. Getting enough folate is especially important in the first trimester, during which the nervous system forms. However, myelination happens later in the baby’s development. Exactly how it is affected by prenatal folate intake remains to be determined [63, 64].
12) Pantothenic Acid/Vitamin B5
Chickens deficient in pantothenic acid developed skin irritation, feather abnormalities, and spinal nerve damage associated with the degeneration of the myelin sheath .
Human data are lacking.
Some studies described interactions among phosphatidylserine, cognitive activity, cognitive aging, and retention of cognitive functioning ability. There are insufficient data to draw conclusions on the effects of phosphatidylserine on myelin in humans, though .
Early research suggests that phosphatidylserine is required for healthy nerve cell membranes and myelin .
Additionally, the aging of the human brain has been associated with biochemical alterations and structural deterioration that impair neurotransmission .
Supplemental phosphatidylserine (300 to 800 mg/d) seems to be absorbed well in humans and likely crosses the blood-brain barrier. Scientists are investigating whether it slows, halts, or reverses biochemical alterations and structural deterioration in nerve cells .
According to some scientists, this compound may support human cognitive function: short-term memory formation, long-term memory consolidation. It’s also been hypothesized to affect the ability to create new memories, retrieve existing memories, learn and recall information, focus attention, reason and solve problems, and communicate verbally .
Further clinical trials are required.
Vitamin B1 may help with the development of the myelin sheath, according to research in thiamine-deficient rats. Scientists think it is required both by the nerve cells and by other supporting cells in the nervous system [68, 69].
This B vitamin is being researched in neurodegenerative diseases such as Parkinson’s, Alzheimer’s, and Huntington’s disease .
16) Keto Diets
The impact of keto diets on myelination is still unclear and proper clinical trials are lacking. Carefully consult your doctor before switching to a keto-type diet.
Some scientists have proposed that ketones (3-hydroxybutyrate) may help support myelin growth by being a source of energy and fuel for lipids .
The ketogenic diet might improve myelination by compensating for a certain enzyme (AGC1, which helps make N-acetylaspartate in oligodendrocytes) that causes seizures and poor development in people who lack this enzyme. Much more research is needed to see if ketogenic diets are beneficial for people with this rare type of genetic disorder .
Cholesterol is an essential constituent of myelin. The dry mass of myelin is about 70 to 85% lipids. Cholesterol is needed for myelin membrane growth. Its presence is needed in the membranes in order for the sheath to function normally .
And although cholesterol is harmful in excess, clinical trials should examine whether getting sufficient amounts from nutritious foods like eggs, sardines, or yogurt may be healthy and good for myelination. But be sure to talk to your doctor before increasing your intake of high-cholesterol foods.
Make sure to speak with your doctor before taking any supplements. Let them know about any prescription or over-the-counter medication you may be taking, including vitamins and herbal supplements.
If you and your doctor agree that supplementing is a good idea, choose products made by a trusted and reliable manufacturer.
Remember that dietary supplements have not been approved by the FDA for medical use. Supplements generally lack solid clinical research. Regulations set manufacturing standards for them but don’t guarantee that they’re safe or effective.
Evidence is lacking to recommend any of the supplements listed below for myelination. Early animal or cellular research has explored whether the following supplements increase myelin:
1) Gotu Kola
4) SAMe and Methylation
7) Grape Seed Extract (Body)
8) Lion’s Mane
9) Ginkgo (Body)
10) Supplemental Lithium
Treatment of adult mice with lithium after facial nerve crush injury stimulated the expression of myelin genes, restored the myelin structure, and accelerated the recovery of whisker movements .
Lithium also promoted remyelination of the sciatic nerve after crush .
The effects of regular and low-dose lithium on myelination in humans are unknown. Clinical trials are needed.
Scientists are investigating whether:
- PQQ increases myelin in Schwann cells .
- Quercetin increases myelin-producing cells (oligodendrocytes) after injury .
- The antioxidant flavonoids luteolin, quercetin, and fisetin can reduce the amount of myelin macrophages break down (phagocytosis) 
The impact of these compounds on myelination hasn’t been explored in animals or humans.
Other Factors & Pathways that May Increase Myelin
This section summarizes the science behind hormonal, cellular, and drug-related factors that may increase myelin. Our aim is to discuss the research findings.
Do not take any of the below-mentioned substances without talking to your doctor.
Some of the substances listed here can have detrimental health effects if used inappropriately. Be sure to discuss all your medications, supplements, and lab results with your doctor.
Progesterone is available only by a doctor’s prescription. It is indicated only for specific hormonal disorders in women.
The delivery of natural progesterone, however, represents a challenge because of its metabolism in the digestive tract and liver .
Recently, the intranasal route of progesterone administration has received research attention for easy and efficient targeting of the brain. Clinical trials need to further explore these formulations .
Progesterone in the brain is derived from glands or from local synthesis by neural cells. Stimulating the natural formation of progesterone is currently explored as an alternative strategy for neuroprotection, axonal regeneration, and myelin repair .
4) Thyroid Hormones
Estimates suggest that men are less likely to develop multiple sclerosis than women .
According to limited research, testosterone stimulates the formation of new myelin and reverses myelin damage in chronically demyelinated brain lesions (oligodendrocytes, working via the androgen receptor) in animals .
Clinical trials (phase II) have found treatment with testosterone can increase gray matter in males with multiple sclerosis. However, its effect on white matter-where myelin is located–hasn’t been explored .
Researchers are studying if erythropoietin (EPO) induces the expression of myelin genes in oligodendrocytes. These genes have been linked with neuron repair, possibly by inducing remyelination after myelin damage. However, this only happens in the erythropoietic EPO receptor (EPOR)-expressing CG4 cells .
9) Acetylcholine and Acetylcholinesterase Inhibitors
Cholinergic treatments, such as acetylcholinesterase inhibitors (AChEIs), may have beneficial effects on myelination, myelin repair, and myelin integrity .
Increasing cholinergic stimulation helps the myelination process .
The acetylcholine muscarinic receptors may increase the survival of precursor cells that increase myelin .
10) Brain-Derived Neurotrophic Factor
The neurotrophin brain-derived neurotrophic factor (BDNF) helps regulate myelin formation in the nervous system. An increase of BDNF levels has been linked with an increase in the rate of myelination in animal and cellular studies. Scientists think this causes an increase in myelin content and thickness .
11) Nerve growth factor
Cellular research is investigating whether NGF promotes axonal regeneration, survival, protection, and production of oligodendrocytes and facilitates their migration to the sites of myelin damage .
12) CB1 Cannabinoid Receptor
13) GSK3b Inhibitors
According to some poorly-researched theories, GSK3β inhibition stimulates the regeneration of myelin-forming cells and remyelination following chemically induced demyelination (oligodendrocytes) .
N-acetylaspartate (NAA) may supply acetyl groups for myelin synthesis. Some researchers think it’s needed for the formation and maintenance of myelin.
RXRgamma must combine with the Vitamin D Receptor to induce gene expression and create these myelin-producing cells .
No animal or human data are available.
16) PPAR-delta and PPAR-gamma
A variety of factors might increase/decrease their function.
17) Neuregulin 1
NRG1 is a protein that helps increase Schwann cells. Scientists think neuregulin 1 is important for synaptic plasticity, inhibiting the amygdala (to shut down anxiety), myelination (Schwann cell maturation, survival, and motility), and heart function (cardiac growth factor). Human studies are needed .
Glial cell line-derived neurotrophic factor (GDNF) seems to be capable of increasing axonal regeneration myelin in cells, but its effects in animals and humans are unknown .
We don’t know how pregnenolone might affect myelination in animals or humans. Pregnenolone is considered an unapproved drug by the FDA. We highly recommend against taking it.
Pregnenolone is a neurosteroid produced in the body. According to some theories, these brain-produced hormones known as neurosteroids may regulate the synthesis and repair of myelin. This theory has not been verified, though.
Pregnenolone is a precursor of other steroid hormones. Research on Schwann cells is studying if natural increases in pregnenolone can raise myelin formation .
Epidermal Growth Factor Receptor (EGFR) and ErbB3 receptor tyrosine kinase:
- Epidermal growth factor receptor plays an important role in myelination and remyelination. EGFR signaling hypothetically increases myelin repair and myelination .
- ErbB3 receptor tyrosine kinase is a receptor located on Schwann cells. Inhibition of its expression may, theoretically,l result in reduced myelination .
Factors that May Reduce Myelination
There’s not enough reliable information about factors that may reduce myelination. Most of the studies outlined below deal with associations or were conducted in animals or cells. Human data are lacking.
We’re outlining the following factors to present research findings only.
If you’re worried about myelination, talk to your doctor to get accurate diagnosis, treatment, and recommendations on complementary brain-healthy habits that you can incorporate into your daily routine.
It’s thought that inflammatory cytokines reduce myelination .
Myelin and oligodendrocyte (OL) destruction occur in cultured preparations subjected to cytokines such as TNF alpha and lymphotoxin (LT) .
Multiple sclerosis is a disease that causes demyelination. Some studies have shown these and other cytokines to be elevated at lesion sites and in the Cerebrospinal fluid of multiple sclerosis (MS) patients, with similar findings in animal models. More human studies are needed .
Teen binge drinking is associated with low frontal white matter integrity .
In rats, adolescent binge drinking reduced the size of the corpus callosum, and degraded myelin basic protein in the gray matter .
Myelin was also damaged on axons in the prefrontal cortex (medial) in adolescent rats who binge drank – and heavier drinking predicted worse performance on the working memory task in adulthood .
These findings establish a causal role of voluntary alcohol on myelin and give insight into specific prefrontal axons that are both sensitive to alcohol and could contribute to the behavioral and cognitive impairments associated with early-onset drinking and alcoholism .
Statins are drugs that help treat heart disease. Some controversial animal studies suggest that statins may have a negative impact on oligodendrocytes and myelin formation. Large-scale human data is needed to verify these claims .
4) EMF Exposure
5-6) SIRT1 and AMPK Activation
SIRT1 inactivation increases the production of oligodendrocytes (myelin-producing cells). In mice, SIRT1 inactivation will lead to oligodendrocyte production, which then increases the formation of myelin and white matter abnormalities .
Likewise, when AMPK levels are high in animals, myelin production is slowed .
Human research should explore these links.
Limitation and Caveats
There are many different models that are cited when we say that a certain factor may increase or decrease myelin. As mentioned, the studies brought down do not provide enough evidence to make a conclusion that they will increase myelin in humans.
The article is simply listing these as potential contenders for increasing myelin in humans.This post is to be used as a springboard for you to to do further research.
Want More Targeted Ways to Enhance Brain Function?
If you’re interested in natural and targeted ways of improving your cognitive function, we recommend checking out SelfDecode’s Limitless Mind DNA Protocol. It gives genetic-based diet, lifestyle and supplement tips that can help improve your cognitive function. The recommendations are personalized based on your genes.
SelfDecode is a sister company of SelfHacked. The proceeds from your purchase of this product are reinvested into our research and development, in order to serve you better. Thanks for your support!