Ashwagandha: Ancient Medicine for Modern Adrenals

Over the past few years, dozens of Moon Milk recipes have appeared on various culinary and wellness blogs. These beautifully colorful and fragrant bedtime drinks are a trendy twist on the traditional Ayurvedic preparation of warm milk with an adaptogenic herb, usually Ashwagandha, given at bedtime to promote restorative sleep. Cow, coconut or nut milk may be used, and recipes often include other herbs to help promote sleep and alleviate stress, such as nutmeg, chamomile, skullcap or lavender. Variations range from a more traditional Golden Milk with turmeric and warming spices featured on Bon Appetit, to the beautifully fragrant Vanilla Rose Moon Milk, to the visually stunning Mermaid Latte made with blue matcha.

For over 3000 years, Ashwagandha has been used as a "Rasayana" or rejuvenator within Ayurvedic medicine, to promote youthful vigor, muscle strength and endurance

Moon Milk is just one way to take Ashwagandha (Withania somnifera), an Ayurvedic botanical medicine that is enjoying a renaissance for addressing the health issues that accompany chronic stress. For over 3000 years, Ashwagandha has been used as a "Rasayana" or rejuvenator within Ayurvedic medicine, to promote youthful vigor, muscle strength and endurance [1].  Similarly, in Western herbalism, Ashwagandha is valued as an adaptogen – an herbal modulator which can help restore hormone balance and healthy function in various body systems, but especially the adrenal glands, helping to promote stress resistance and energy throughout the day.

Ashwagandha has gained in popularity so much in recent years that, here in the Portland Metro area, we need not leave the urban growth boundary to find a farmer cultivating this herb in and around the city. In fact, it is one of the most frequently discussed botanicals among ZRT Laboratory’s Clinical Consultants on any given day, whether in the context of adrenal stress profiles, male and female hormone profiles, weight management or neurotransmitter testing

Current clinical research largely supports the traditional uses of this plant in promoting a more “youthful” physiology in terms of stress resilience, hormone levels including cortisol, thyroid hormones, DHEA and testosterone, body composition, sexual function, memory and cognition. In this article, we will focus on recent randomized, double-blind, placebo-controlled studies supporting these stress-related health benefits of Ashwagandha:

Modulating Stress Response and Cortisol Levels

Stress is all too familiar to most of us as a state of mental or emotional strain or tension. The stress response is reflected in the body by an acutely elevated cortisol level which can be associated with agitation, irritability, anxiety, and sleep disturbances. Under ordinary circumstances, cortisol levels should return to the normal range within several hours following an acute stressor. However, if stressors persist, the brain and adrenal gland axis may become downregulated, and with significant enough hypothalamus-pituitary-adrenal (HPA) axis dysfunction cortisol levels may drop to normal and eventually low levels. Chronic stress over a prolonged period of time often leads to conditions such as weight gain in the waist, muscle and bone loss, depression, and immune suppression.

As an adaptogen, Ashwagandha is well-known for reducing stress and anxiety in humans. This effect was supported by a 2014 systematic review of 5 human trials which concluded that treatment with Ashwagandha resulted in significantly greater score improvements (than placebo) in outcomes on various symptom scales of stress and anxiety [2].

In addition to improving subjective symptoms of stress and anxiety, Ashwagandha may help regulate cortisol levels.

In addition to improving subjective symptoms of stress and anxiety, Ashwagandha may help regulate cortisol levels. Clinically and anecdotally, we observe Ashwagandha and other adaptogens to modulate both high and low cortisol levels and support a normal diurnal cortisol curve, which is highest in the morning upon waking and falls throughout the day, reaching the lowest cortisol level around midnight. Most clinical research has focused on Ashwagandha’s effect on down-regulating high cortisol levels and less on helping the adrenals raise cortisol levels when low. In one study, 64 subjects with a history of chronic stress were randomized to receive either 300 mg of Ashwagandha root extract, or a placebo twice daily for 60 days. Not only did the treatment group exhibit significant reductions in scores on all the stress-assessment scales, but their serum cortisol levels were also substantially reduced to within normal ranges relative to the placebo group [3].

Supporting Restorative Sleep

In a small study exploring the safety and tolerability of Ashwagandha in healthy volunteers, a significant percentage reported improved sleep quality [4]. There is currently a prospective, randomized, double-blind placebo-controlled study underway to examine the effects of Ashwagandha on nonrestorative sleep, which is often both a result of stress and a direct cause of high cortisol levels as the body attempts to cope with chronic sleep deprivation or poor sleep quality [5].

It’s Not Just Cortisol; Anxiolytic Effects via GABA Modulation

A 2018 review article identifies Ashwagandha as one of only a handful of phytomedicines able to modulate the activity of the neurotransmitter GABA to exert an anxiolytic (calming) effect. This effect was first demonstrated in animal models of anxiety, and later observed in human clinical trials on male fertility, in which Ashwagandha demonstrated GABA-mimetic activity [6].

Managing Weight Gain Related to Chronic Stress

Weight gain associated with chronic stress is a growing health concern, with over 70% of the adult US population now in the overweight and obesity BMI categories. Because of Ashwagandha’s anxiolytic effects and ability to improve serum cortisol levels, researchers conducted a study to assess whether it could also reduce hunger and stress-eating behaviors. A total of 52 subjects under chronic stress received either 300 mg of Ashwagandha or placebo twice daily. Primary efficacy measures were Perceived Stress Scale and Food Cravings Questionnaire. Secondary efficacy measures were Oxford Happiness Questionnaire, Three-Factor Eating Questionnaire, serum cortisol, body weight, and body mass index. Each subject was assessed at the start and at 4 and 8 weeks. The treatment group showed significant improvements in both primary and secondary measures, suggesting that Ashwagandha root extract may be a useful adjunct to other strategies for body weight management in adults under chronic stress [7].

Small studies suggest Ashwagandha may also help improve upper and lower-body strength and support a favorable body composition, and is associated with significant increases in muscle mass and when used in conjunction with a resistance training program in young, recreationally active men over a period of 8 to 12 weeks [8]. A higher proportion of lean muscle mass in turn helps to maintain a healthy metabolic rate.

Dosing and Considerations

In the studies mentioned above, Ashwagandha was typically given in doses of 250 to 600 mg/day, in two divided doses. It can be taken as a tea, tincture, powdered herb, or in capsules, and is generally well-tolerated with few side effects. Although Ashwagandha itself can be given at any time of day and even assist with restorative sleep, it is often found in combination formulas with other adrenal adaptogen herbs, bovine adrenal glandular material, vitamins C and B5, and other nutrients that are best dosed in the morning and at lunchtime to avoid overstimulation near bedtime. 

Ashwagandha is most effective when combined with lifestyle measures to support healthy adrenal function and continued production of cortisol, including adequate sleep, proper diet with adequate protein and vitamins B and C, and stress management practices such as yoga and meditation. Before incorporating herbs like Ashwagandha into your routine, it is best to determine where you are out of balance. ZRT’s adrenal stress, weight management, sleep balance, and neurotransmitter testing can help you and your doctor pinpoint your imbalances to ensure optimal clinical outcomes. Enjoying a cup of Moon Milk or Ashwagandha tea as a part of a relaxing bedtime ritual may be the perfect way to help release the stresses of the day and prepare for a restful night – and to do it all again tomorrow.  Sweet dreams!

Moon Milk Recipes Too Beautiful Not to Try:

Related Resources


[1] Mirjalili MH, et al. Steroidal lactones from Withania somnifera, an ancient plant for novel medicine. Molecules. 2009;14(7):2373-93.

[2] Pratte MA, et al. An alternative treatment for anxiety: a systematic review of human trial results reported for the Ayurvedic herb ashwagandha (Withania somnifera). J Altern Complement Med. 2014;20(12):901-8.

[3] Chandrasekhar K, et al. A prospective, randomized double-blind, placebo-controlled study of safety and efficacy of a high-concentration full-spectrum extract of ashwagandha root in reducing stress and anxiety in adults. Indian J Psychol Med. 2012;34(3):255-62.

[4] Raut AA, et al. Exploratory study to evaluate tolerability, safety, and activity of Ashwagandha (Withania somnifera) in healthy volunteers. J Ayurveda Integr Med. 2012;3(3):111-4.

[5] Deshpande A, et al. Study protocol and rationale for a prospective, randomized, double-blind, placebo-controlled study to evaluate the effects of Ashwagandha (Withania somnifera) extract on nonrestorative sleep. Medicine (Baltimore). 2018;97(26):e11299.

[6] Savage K, et al. GABA-modulating phytomedicines for anxiety: A systematic review of preclinical and clinical evidence. Phytother Res. 2018;32(1):3-18.

[7] Choudhary D, et al. Body Weight Management in Adults Under Chronic Stress Through Treatment With Ashwagandha Root Extract: A Double-Blind, Randomized, Placebo-Controlled Trial. J Evid Based Complementary Altern Med. 2017;22(1):96-106.

[8] Wankhede S, et al. Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trial. J Int Soc Sports Nutr. 2015;12:43.