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Ashwagandha Benefits for the Brain, Thyroid, Muscles & More
May 15, 2023
Ashwagandha (aka Withania somnifera) is an adaptogenic herb that’s popular in Ayurvedic and traditional medicine. It has been used for more than 2,500 years and has been extensively researched (used in over 200 studies) for its potential thyroid-modulating, neuroprotective, anti-anxiety and anti-inflammatory properties.
In India, it is known as the “strength of the stallion” because it traditionally has been used to strengthen the immune system after illness. It’s also been referred to as “Indian ginseng” because of its ability to enhance your stamina and work as a natural stress reliever, and those aren’t the only benefits of ashwagandha.
Like all adaptogenic herbs, it helps the body maintain homeostasis, even in moments of emotional or physical stress. In Ayurvedic medicine, it’s characterized as a “rasayana,” which means that it’s used to support physical and mental health, defend the body against disease and damaging environmental factors, and slow the aging process.
Research published in the International Journal of Home Science indicates that 1,000 milligrams of dehydrated ashwagandha root powder contains the following:
- 2.5 calories
- 0.05 gram carbohydrates
- 0.04 gram protein
- 0.032 gram fiber
- 0.03 milligram iron
- 0.02 milligram calcium
- 0.08 microgram carotene
- 0.06 milligram vitamin C
Ashwagandha contains many beneficial elements, including flavonoids and antioxidants, such as catalase, superoxide dismutase and glutathione, which is known as the “mother of all antioxidants.”
It also contains alkaloids, amino acids (including tryptophan), neurotransmitters, sterols, tannins, lignans and triterpenes. These valuable compounds allow for the herb’s pharmacological activities and are responsible for the many ashwagandha benefits.
What are some ashwagandha benefits for men and women? Here are some of the top uses that are supported by research:
1. Improves Underactive Thyroid Function
One of the most incredible aspects of adaptogen herbs is that they help people with thyroid problems. Ashwagandha has been shown to support a sluggish thyroid for people diagnosed with Hashimoto’s disease, or underactive thyroid.
For the millions of people who struggle with thyroid problems, many of whom don’t even know it, it may serve as the solution they’ve been waiting for. These ashwagandha health benefits for the thyroid also account for the herb’s benefits for weight loss since thyroid issues can lead to weight fluctuations.
In a 2017 pilot study published in the Journal of Alternative and Complementary Medicine, ashwagandha benefits for helping patients with subclinical hypothyroidism were evaluated. The 50 participants were diagnosed with thyroid disorder but didn’t display obvious symptoms of thyroid deficiency.
During an eight-week period, the treatment group received 600 milligrams of ashwagandha root extract daily, and the control group received starch as the placebo. Researchers found that the extract improved serum thyroid stimulating hormone (TSH) and thyroxine (T4) levels significantly compared to placebo.
It was concluded that the herb may be beneficial for normalizing thyroid levels in patients with hypothyroidism.
Another study published in the Journal of Ayurveda and Integrative Medicine also found that ashwagandha has thyroid-enhancing properties. In the study, patients with bipolar disorder used the herb to improve cognitive function for an eight-week period.
Lab testing found that some of these patients experienced T4 increases during the treatment period, although that was not the original purpose of the study. Research suggests that, since ashwagandha increases thyroid function, it may not be suitable for people with hyperactive thyroid, such as those with Graves’ disease.
2. Helps Relieve Adrenal Fatigue
Research shows that ashwagandha may be useful in supporting adrenal function and helping overcome adrenal fatigue. Your adrenals are endocrine glands that are responsible for releasing hormones, specifically cortisol and adrenaline, in response to stress.
If your adrenals are overtaxed due to an overabundance of emotional, physical or mental stress, this can lead to a condition referred to as adrenal fatigue.
When your adrenals become exhausted, this can also disrupt other hormones in your body, including progesterone, which can cause infertility and lower levels of DHEA, a hormone that’s tied to longevity and maintaining a strong body.
3. Combats Stress and Anxiety
One of the most well-known ashwagandha benefits is its ability to work as a natural remedy for anxiety. In a 2009 study published in PLOS One, ashwagandha proved to be comparable to common pharmaceutical drugs lorazepam and imipramine but without the adverse effects.
In the 12-week, controlled study, 75 participants with anxiety were divided into two groups, one that received naturopathic care and another that received standardized psychotherapy intervention. The naturopathic care group received dietary counseling, deep breathing relaxation techniques, a standard multivitamin and 300 milligrams of ashwagandha twice daily.
The psychotherapy intervention group received psychotherapy, deep breathing relaxation techniques and placebo pills twice daily.
When anxiety levels were measured after the 12-week period, the group that received ashwagandha had anxiety scores that decreased by 55 percent, and the psychotherapy group’s scores decreased by 30.5 percent.
Significant differences between the two groups were also found in mental health, concentration, social functioning, vitality, fatigue and overall quality of life, with the ashwagandha group displaying greater clinical benefits.
In addition to these positive findings, researchers indicated that no serious adverse effects occurred in either group. A major ashwagandha benefit is that there are no or minimal adverse reactions when taking it.
Conversely, antidepressant and anti-anxiety medications may cause drowsiness, insomnia, loss of sexual desire and increased appetite, among other negative effects.
4. Helps Improve Depression
Not only does ashwagandha benefit people who deal with anxiety and chronic stress, but it can also be helpful for people who experience signs of depression. The herb improves resistance toward stress, and studies show that it thereby improves people’s self-assessed quality of life.
In a 2000 experimental study involving rats, ashwagandha efficacy was compared to the antidepressant medication imipramine. Researchers found that it exhibited antidepressant effects that were comparable to imipramine when rats were exposed to “behavioral despair” and “learned helplessness” tests.
It was concluded that ashwagandha can be used as a mood stabilizer in clinical conditions of depression.
5. Balances Blood Sugar Levels
Ashwagandha has been evaluated for its anti-diabetic effects, which are possible because of the presence of phenolic compounds, including flavonoids. Research shows that flavonoids possess hypoglycemic activities, and a study involving rodents concluded that both ashwagandha root and leaf extracts helped achieve normal blood sugar levels in diabetic rats.
An animal study published in Reports of Biochemistry and Molecular Biology found that when ashwagandha was given to fructose-fed rats, it inhibited the fructose-induced increases in glucose, insulin resistance and inflammation.
This data suggests that ashwagandha extract may be helpful in improving insulin sensitivity and reducing inflammatory markers in humans.
6. Helps Fight Cancer
Research suggests that ashwagandha has promising anti-tumor effects, can help reduce tumor cell growth and may work to prevent cancer cells from growing.
The extract has been shown to help inhibit the proliferation of cancer cells — specifically breast, lung, stomach and colon cancer cells, which are among the leading types of cancers in the world. It’s believed that ashwagandha helps prevent the growth of cancer cells mostly due to its immune-boosting and antioxidant abilities.
In addition to the anti-cancer ashwagandha benefits that have been displayed in multiple studies, researchers also suggest that the herb can help reduce the adverse reactions of anti-cancer agents that can reduce immunity and quality of life.
According to an overview published in the African Journal of Traditional, Complementary and Alternative Medicines, ashwagandha acts as an immunomodulator that can enhance the life span of cancer patients, who are especially at risk of lowered immunity.
An animal study published in the Journal of Ethnopharmacology found that supplementing with ashwagandha was correlated with an increase in white blood cells within the body. This indicates that the immune system is better able to protect the body from disease and harmful invaders when using this herb.
The decreased count of white blood cells in the body after chemotherapy is a major concern because it puts cancer patients at a much higher risk of health issues, like contracting an infection. This is why this herb may serve as a complementary addition to conventional cancer treatments.
7. Reduces Brain Cell Degeneration and Improves Memory
Emotional, physical and chemical stress can have damaging effects to the brain and nervous system. Recent research shows that ashwagandha Withania somnifera is more than a stress reliever — it also protects the brain from cell degeneration, which can lead to neurodegenerative diseases like Alzheimer’s and Parkinson’s.
One of the main reasons it is so effective at healing the brain is because it contains powerful antioxidants that destroy the free radicals that cause aging.
Withaferin A and withanolide D are the two main withanolides in ashwagandha that are used to improve cognitive function. Withanolides are naturally occurring steroids that are commonly present in plants of the nightshade family.
When these steroids were injected into rodents to test their cognitive-improving abilities, researchers found that they helped promote cell outgrowth, reverse behavioral deficits and plaque buildup, and reduce amyloid beta burden, which is crucially involved in the development of Alzheimer’s disease.
A 2017 pilot study published in the Journal of Dietary Supplements suggests that ashwagandha effectively enhanced both immediate and general memory in people with mild cognitive impairment.
The herb was also able to improve attention, information processing speed and mental skills. The study involved 50 adults who received 300 milligrams of ashwagandha root extract or placebo for an eight-week period. Researchers concluded that ashwagandha treatment was able to boost memory and other cognitive skills.
8. Boosts Immune Function
Because ashwagandha works as an adaptogen that can reduce the body’s stress hormones, it can help boost your immune system and reduce inflammation within the body. Animal and laboratory research shows that it can enhance immune function by increasing immunoglobulin production.
It is also able to promote an anti-inflammatory environment by suppressing pro-inflammatory cytokines. By downregulating the immune system when it’s compromised, this adaptogenic herb might be a useful tool in the treatment of various inflammatory disorders.
9. Increases Stamina and Endurance
Studies show that ashwagandha can boost endurance during physical activity by sharpening brain function and reducing bodily pain. Due to its positive, calming, energizing effects on the brain and its ability to lower stress hormones, it’s helped improve concentration, motivation and stamina in conducted studies.
A 2015 double-blind, randomized and placebo-controlled study conducted in India evaluated the efficacy of ashwagandha extracts in enhancing cardiorespiratory endurance in 50 healthy adult athletes.
During a 20-minute shuttle run test, the oxygen consumption of each participant’s peak physical exertion was measured. The participants were also given a questionnaire about their physical health, psychological health, social relationships and environmental factors to assess changes in their quality of life after ashwagandha treatment.
Researchers found that ashwagandha extracts improved cardiorespiratory endurance at eight and 12 weeks of treatment and significantly improved the quality of life scores of the participants in the extract group.
10. Helps Increase Muscle Strength
Ashwagandha Withania somnifera may be a helpful tool for people engaging in resistance training and other forms of exercise that can be strenuous on your muscles.
A 2015 study published in the Journal of the International Society of Sports Nutrition highlights that ashwagandha supplementation was associated with significant increases in muscle mass and strength. The eight-week study involved 57 males between the ages of 18 and 50 with little experience in resistance training.
The men in the treatment group consumed 300 milligrams of ashwagandha root extract twice daily, and the control group consumed starch placebos.
Researchers found that the treatment group had significantly greater increases in muscle strength on the bench-press and leg-extension exercises. Those receiving ashwagandha also displayed significantly greater muscle size increase of the arms and chest, a significantly greater reduction of exercise-induced muscle damage, increased testosterone levels, and greater decrease in body fat percentage.
Even with increased muscle mass, your joints must be strong to operate at peak performance levels. Ashwagandha appears to help with that, too.
Clinical trials studying general joint pain and joint pain related to rheumatoid arthritis have found extremely positive results, with the herb relieving major pain and causing no documented side effects.
11. Helps Improve Sexual Function and Fertility
In Ayurvedic medicine, ashwagandha has been used as a natural aphrodisiac that can help improve sexual dysfunction. It is also used to boost testosterone levels and improve male fertility.
A pilot study published in BioMed Research International set out to determine the efficacy and safety of 300 milligrams of ashwagandha root extract supplementation twice daily for eight weeks for improving sexual function in 50 healthy women. Researchers found that the treatment group displayed significantly higher improvements, compared to placebo, in sexual function scores, specifically in areas of arousal, lubrication and orgasm.
Another study was conducted to analyze the spermatogenic activity of ashwagandha in patients with low sperm concentrations and possible male infertility. Forty-six males participated in the study and received either 675 milligrams of ashwagandha divided into three doses per day for a 90-day period or a placebo.
At the end of the treatment period, semen parameters and serum hormone levels were estimated. Researchers found that there was a 167 percent increase in sperm count, 53 percent increase in semen volume and 57 percent increase in sperm motility among the participants treated with ashwagandha. In the placebo group, the improvements were minimal.
Additionally, a 2010 study published in Fertility and Sterility describes that ashwagandha supplementation was able to improve testosterone levels in 75 men who were undergoing infertility screening. It also reduced oxidative stress and improved levels of diverse antioxidants in the treatment group.
How to Use
Ashwagandha Withania somnifera supplements are widely available online and in health food or vitamin stores. The most popular form of the herb is the root extract, but leaf extracts are also available. You can find the extracts in capsule and powder forms, and ashwagandha tea is available as well.
When purchasing ashwagandha supplements, make sure they’re standardized for human consumption. The withanolide content should range from 1 percent to 10 percent, but not all supplements are labeled with this information.
Purchasing a high-quality supplement produced with gold-star standards is the best way to guarantee you get a product high in withanolides. The higher the withanolide content, the stronger the effects of the supplement.
Of course, organic ashwagandha is preferable to non-organic.
When supplementing with an organic ashwagandha power or other product, the general recommendation is starting with 300 to 500 milligrams per day, with withanolides in a range of 5 percent to 10 percent. Slowly increase your ashwagandha dosage, watching for potential adverse effects.
Many supplements recommend between 1,000–1,500 milligrams per day at full dosage. Various sources claim the optimal ashwagandha dosage to take may be as high as 6,000 milligrams each day.
It’s smart to do this under the guidance of your naturopathic practitioner or health care provider, and when to take ashwagandha depends on why you are taking it.
A study published in the Journal of Ayurvedic and Integrative Medicine found that in the form of extract in capsules, with gradual escalating doses from 750 milligrams per day to 1,250 milligrams per day, ashwagandha was well-tolerated and safe on biochemical organ function and hematological tests. It was able to help improve quality of sleep, lower cholesterol levels and promote muscle strength as well.
You may find that ashwagandha doesn’t have the most appealing smell, but if you choose to use it in powder form, you can mix it with other foods or drinks to make it more pleasant and create a healing tonic. You can try adding ashwagandha powder to an energy ball recipe, a turmeric or pumpkin spice latte, or even to a smoothie.
Drinking ashwagandha tea is also a popular way to consume the herb, and you can add a little organic honey to improve the flavor.
How long does it take for ashwagandha to work? It may take two weeks or more to notice the benefits of ashwagandha, so be consistent. It takes some time to reverse the damage of chronic stress and increased cortisol levels.
There isn’t enough evidence to say that taking the herb for a long-term period is safe, but there are several studies that include treatment periods lasting several months.
Maca root and ginseng are other popular adaptogenic herbs that are used to boost mood and promote brain function. They have similarities and differences that you should be aware of, including the following:
- Ashwagandha, maca root and ginseng are all plants that have been used for centuries for their medicinal properties.
- All three plants contain powerful antioxidants and are known to help improve memory and brain function, boost mood, improve sexual function, regulate blood sugar levels, reduce inflammation, and increase energy levels.
- All three plants are widely available in extract, capsule and powder forms, which are most commonly made from the roots of the plants, meant for therapeutic use.
- These three plants have very different tastes. Ashwagandha is known for its bitter taste and horse-like smell, which is why it works better in capsule form or as a powder mixed with other foods. Maca root has an earthy, nutty taste, and ginseng has a bitter-spicy flavor.
- Ginseng is commonly used in Traditional Chinese Medicine, maca root traces back to the ancient Peruvians and ashwagandha is a staple in Ayurvedic medicine and among the most popular Ayurvedic herbs.
- The recommended doses of each herb is different. For ginseng, effective doses range from 200 to 900 milligrams daily, the daily dose for maca root is one to three tablespoons and, for ashwagandha, the daily recommended dose is 1,000 to 1,500 milligrams per day.
Risks and Side Effects
Ashwagandha is made up of steroidal lactones or withanolides, including withanolide A, withaferin A and withanone. These structures are unique to this herb and have different medicinal effects.
Some parts of the plant contain more of these compounds than others, so when you choose an ashwagandha extract, you should pay attention to where it comes from. Leaf extracts usually contain higher levels of withaferin A than root extracts.
When taken in appropriate doses for therapeutic use, it has been regarded as safe for human consumption. Some possible side effects of ashwagandha include upset stomach, vomiting and diarrhea. If you notice any of these issues, stop taking the herb right away.
It should never be used by women who are pregnant or breastfeeding. There is some evidence it may induce miscarriages, and there is no available safety information about breastfeeding while taking the herb.
People using diabetes medications, blood pressure medications, medications that suppress the immune system, sedatives or medications for thyroid problems should not use ashwagandha unless they’ve consulted with their doctors first.
Those with hyperthyroidism may notice an additional increase of thyroid function when taking the herb and should only do so under the controlled supervision of a doctor, if at all. Because the herb also works to modify these conditions, there may be adverse interactions.
It is possible that ashwagandha could increase symptoms of autoimmune diseases like multiple sclerosis, lupus and rheumatoid arthritis.
If you are going to have surgery that requires anesthesia, you should stop taking ashwagandha at least two weeks beforehand in case the herb further slows down your central nervous system.
How to Avoid Adverse Reactions:
In order to get the most from your supplement, be sure to use as directed, and follow the instructions for how to take ashwagandha carefully. It’s also advisable to start with a low dose and work your way up to monitor and assess your tolerance.
Additionally, be sure to select a high-quality supplement to maximize the health benefits of ashwagandha while also preventing ashwagandha capsules side effects. Buy from a reputable retailer, read the ashwagandha reviews from other consumers and check the ingredients label to pick a product that is free of chemicals, additives and fillers.
It’s also important to look for supplements that contain between 1 percent and 10 percent withanolides, which are the main phytochemicals found in ashwagandha.
If you do experience any ashwagandha root or ashwagandha tea adverse effects, consider decreasing your dosage to see if symptoms persists. For serious side effects, discontinue use, and consult with your doctor.
How Much Ashwagandha Is Safe?
So how much ashwagandha should you take per day? Although there’s no official recommended ashwagandha dosage, many recommend taking around 300–500 milligrams per day and working your way up to around 1,000–1,500 milligrams daily.
Although many sources advise taking doses as high as 6,000 milligrams per day, it’s best to stick to a moderate dosage unless under the guidance of a trusted health care practitioner.
- Ashwagandha Withania somnifera is an important herb in Ayurvedic medicine because it serves many purposes and benefits many body systems, including the immune, neurological, endocrine and reproductive systems.
- This is one of the most commonly used adaptogens because of the many ashwagandha benefits. The top and most well-researched health benefits of ashwagandha include improving thyroid function, boosting energy levels, relieving adrenal fatigue, reducing cortisol levels, reducing stress and anxiety, improving depression, and much more.