Ashwagandha's Brain Benefits

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

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, and^21,22,24
• 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

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

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

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.

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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