Life Extension Magazine®
Woman talking with physician on increasing ashwagandha intake

Ashwagandha's Brain Benefits

The herb ashwagandha improves brain function and may defend against cognitive decline.

Scientifically reviewed by: Gary Gonzalez, MD, on May 2021. Written By Rick Wilson.

Ashwagandha has been used in traditional Indian medicine for thousands of years.1

Scientists have identified specific effects that ashwagandha has on brain activity.1-4

In human studies, ashwagandha intake:5,6

  • Improved cognitive performance in healthy adults.
  • Reduced anxiety and stress.

Lab studies show that it may also help protect against structural changes that can lead to Alzheimer's and other forms of dementia.7-10

A Staple of Ancient Medicine

Extracts of ashwagandha's roots and leaves contain a mixture of bioactive compounds, including withaferin A, withanolides, withanosides, and others.2

These compounds function as antioxidants and anti-inflammatory agents. They also act in other ways to protect the brain from disease.

They cross the blood-brain barrier and enter brain tissue, where they can exert beneficial actions.11,12

In healthy adults, ashwagandha taken daily has been shown to improve cognitive performance—with boosts in reaction time, discrimination, vigilance, and other tests of brain function.5

Relieving Anxiety and Depression

Woman holding head due to anxiety

Nearly 10% of American adults suffer from mood disorders like anxiety, depression, and bipolar disorder in any given year.13

Stress and anxiety are often treated with drugs that stimulate the receptor for a neurotransmitter called GABA (gamma aminobutyric acid). These drugs have side effects, including fatigue and cognitive impairment.

Ashwagandha stimulates these same GABA receptors, without the side effects.14,15 Rather than causing fatigue or cognitive impairment, ashwagandha is known to enhance cognitive performance.5

Ashwagandha has long been used to reduce stress and support a healthy mood.14 A review of human trials found that it improved anxiety symptoms, compared to a placebo.6

In animal models of depression, ashwagandha extracts reverse signs of behavioral despair and other abnormalities and improve cognitive function.16-19

In two studies in rodents, the magnitude of this impact was comparable to the effects of imipramine and fluoxetine (Prozac®), two drugs used in humans to treat depression and other disorders.16,17

In patients with schizophrenia, who are prone to anxiety and depression, an ashwagandha extract reduced symptoms of both.20

Protecting Brain Cells

Ashwagandha may protect against various forms of dementia.

In laboratory studies of animal models of Alzheimer's disease, ashwagandha displays various mechanisms known to reduce its progression.

One of the primary features of Alzheimer's is the accumulation of an abnormal protein called beta-amyloid.

This buildup inflicts toxic effects on brain cells and incites aggressive chronic inflammation, which leads to further deterioration of brain function.

Preclinical studies have shown that ashwagandha:

  • Reduces the formation of amyloid in the brain and brain cells,21,22
  • Prevents the accumulation and aggregation of amyloid,23
  • Reduces the toxic impact of existing amyloid, protecting brain cells from injury and inflammation, and21,22,24
  • Aids in removing existing amyloid deposits, reversing Alzheimer's disease pathology.25

Animal models of Alzheimer's also show a drop in two key proteins associated with brain maintenance and repair: brain-derived neurotrophic factor (BDNF) and glial fibrillary acidic protein (GFAP). Ashwagandha helps maintain higher levels of both these protective proteins.26,27

Boosting Acetylcholine

Dried ashwagandha in mortar and pestel

One effect of memory loss caused by Alzheimer's disease is a loss of acetylcholine function.

Acetylcholine is a neurotransmitter used for cell-to-cell communication in the brain. It is vital to normal cognitive function.

Some medications used to treat Alzheimer's inhibit the enzyme that breaks down acetylcholine, boosting its levels. Ashwagandha also blocks this enzyme, increasing acetylcholine levels.8-10

Together, these actions suggest that ashwagandha could help fight some of the primary damage that is among the causes of Alzheimer's disease, while also supporting healthy brain function.

Ashwagandha has also shown promise in preclinical studies of other neurodegenerative diseases, including Parkinson's disease, amyotrophic lateral sclerosis (ALS), and Huntington's disease.1,2,28,29

Defense Against Neurotoxins

Ashwagandha has been found, in preclinical models, to shield against a range of neurotoxins, including lead, aluminum chloride, streptozotocin, scopolamine, kainic acid, and bisphenol A (BPA, a common additive in plastics).1,30,31

One example is glutamate. Glutamate is an amino acid that acts as a neurotransmitter in the brain. Normal levels of glutamate are vital to brain communication.4

What you need to know

Brain Benefits of Ashwagandha

  • Ashwagandha is a plant native to India and surrounding parts of Asia. It has been used in traditional Indian medicine for millennia to promote overall health.
  • Modern science has found that ashwagandha promotes healthy functioning of the brain.
  • Extracts of ashwagandha may protect the brain from damage caused by a wide range of toxins, injuries, and stroke.
  • Oral intake improves cognitive performance in healthy adults and in those with signs of cognitive decline.
  • Ashwagandha reduces stress and anxiety, and relieves symptoms of depression.
  • Research shows that ashwagandha may help protect against forms of dementia, including Alzheimer's disease.

But very high levels of glutamate can cause excitotoxicity—overstimulation of brain cells that can cause them to go haywire, and even die. Some brain injuries, such as traumatic head injuries and stroke, cause a huge release of glutamate that results in further cell death.4

Glutamate excitotoxicity has been found to be a component of the pathology seen in neurodegenerative disorders, such as Alzheimer's disease, Parkinson's disease, ALS, and multiple sclerosis.4

Ashwagandha defends the brain against this damage. In lab studies, pretreatment with ashwagandha extracts before exposure to high levels of glutamate markedly inhibit cell death and other changes associated with excitotoxicity.1,32,33

Helping Stroke Victims

Neurotansmitters in brain affected by glutamate levels

The most common forms of stroke result from a lack of oxygen and blood to the brain, leading to cell dysfunction and death.

In several animal studies of experimental stroke, ashwagandha intake prevented much of this brain damage.34-38 It reduced the size of the brain injury and the biochemical changes that typically accompany stroke.

This helped prevent the behavioral, motor, and cognitive dysfunction that would otherwise have occurred.

These actions, along with its other benefits, make ashwagandha a powerful neuroprotective nutrient.

Summary

The herb ashwagandha has been used for its diverse health benefits for thousands of years.

Ashwagandha extract appears to be beneficial to the brain.

It may shield the brain from damage resulting from exposure to toxins, physical injury, and stroke.

It helps relieve stress and improves symptoms of anxiety and depression.

Ashwagandha also improves cognitive performance and may defend against cognitive decline and dementia.

Additional Brain-Boosting Nutrients

Sage leavesthat can produce extract

Sage

Researchers have identified a unique form of sage that improves cognitive function.

Clinical evidence demonstrated that this proprietary extract increased memory performance in older adults by nearly 60% and improved attention by 250%within hours of ingestion.39

In addition to enhancing cognitive function in humans, this unique sage extract has been shown to increase lifespan by 12% in a C. elegans model of aging.40

Phosphatidylserine

Phosphatidylserine is a phospholipid, one of the structural components of the membranes that surround all cells in the body.41,42 This is especially critical for nerve cells in the brain, because it is their cell membranes that carry nerve impulses throughout the nervous system.43 The myelin that surrounds nerve fibers and aids signal conduction also relies on phosphatidylserine for normal structure and function.

Aging is associated with structural deterioration in the nervous system, which may be reduced by phosphatidylserine's ability to preserve cognitive function.

Blueberries packed with anthocyanins

Blueberry

Blueberries are packed full of anthocyanins, powerful compounds that help protect the plant from oxidative stress. These compounds have been explored in the medical literature for years for their potential health benefits to humans.

Several recent trials in humans have demonstrated that blueberries enhance cognitive function. Not only has blueberry been found to enhance memory and other cognitive performance in older subjects, it improves mood and cognition in children and young adults as well.44-48

Pregnenolone

Pregnenolone, a hormone and hormone-precursor, as well as the derivatives it forms in the brain, have modulatory effects on nervous system function.

Several studies in animals and humans have reported beneficial effects for the brain.49

Pregnenolone appears to be a neuroprotectant, defending the brain from various forms of injury. It has also been found to have positive effects on mood, memory, and other aspects of cognition.


If you have any questions on the scientific content of this article, please call a Life Extension® Wellness Specialist at 1-866-864-3027.

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