Natural medicine has long appreciated the benefits of herbs and food as medicine. One such example of this is adaptogenic herbs, or “adaptogens.” There is a good bit of science behind the benefits of adaptogen herbs that I’ll share with you, all of which deal with their impact on the stress response.
As you probably know, your body is built to release the hormone cortisol to respond to stress, but elevated cortisol levels over long periods of time and chronic stress can affect every physiological system in your body, including your thyroid and adrenal glands.
Cortisol is also known as the aging hormone. When cortisol levels rise, you experience the “fight or flight” response, which stimulates your sympathetic nervous system and your adrenal glands. When this occurs, there is a decrease in your digestive secretions and an increase in blood pressure. In normal life, you experience this response, your body and brain respond to the stressor, your cortisol levels even back out and your body adapts back to normal.
However, people who experience the fight-or-flight responses on a regular basis, many times a day, may experience a state of constant stress, which can burn out your adrenal glands, stress your digestive tract and cause you to age more rapidly. Some people at the highest risk for this include young parents, university students and primary caregivers, like nurses or family members who care for invalid relatives or patients.
Long-term, chronic stress leads to adrenal fatigue and even more potentially dangerous problems, if left untreated. While most researchers and doctors agree that an approach to reduce chronic stress is many-layered, I believe that one powerful approach to naturally relieving stress as well as reducing long-term cortisol levels is by using adaptogenic herbs.
What Are Adaptogens?
Phytotherapy refers to the use of plants for their healing abilities. Adaptogens are a unique class of healing plants: They help balance, restore and protect the body. According to naturopath Edward Wallace, an adaptogen doesn’t have a specific action; it helps you respond to any influence or stressor, normalizing your physiological functions. (2)
The term of adaptogenic herbs or substances was first recorded in 1947 by N.V. Lazarev, a Russian scientist, who used it to describe this non-specific effect that increases the body’s resistance to stress. Defined by two other Russian research scientists in 1958, adaptogens “must be innocuous and cause minimal disorders in the physiological functions of an organism, must have a nonspecific action, and usually [have] a normalizing action irrespective of the direction of the pathological state.” (3)
This effect has been observed in animal studies, finding that various adaptogens have the ability to create this generally increased tolerance to stress. (4)
In his book Adaptogenic Herbs, certified herbalist David Winston gives a list of 15 recognized adaptogens. Today, I’ll discuss the seven I believe to be most beneficial as part of a stress-relieving lifestyle (in addition to other natural stress relievers).
Please note: I am reviewing evidence on individual adaptogenic herbs, not combinations of them often marketed as cortisol blockers.
Top 7 Adaptogenic Herbs
1. Panax Ginseng
Benefit-rich ginseng is one well-known adaptogen, and Asian ginseng (Panax ginseng) is considered by many to be the most potent. In humans, Panax ginseng has been shown to successfully improve subjective calmness and some aspects of working memory performance in healthy young adults. (5)
Another study on ginseng in 2003, this time in rats, observed that Panax ginseng reduced the ulcer index, adrenal gland weight, blood glucose levels, triglycerides, creatine kinase (an enzyme that points to stress- or injury-related damaged of the circulatory system and other parts of the body) and serum corticosterone (another stress-related hormone). The scientists came to the conclusion that Panax ginseng “possesses significant anti-stress properties and can be used for the treatment of stress-induced disorders.” (6)
Interestingly, multiple studies on Panax ginseng have found that it doesn’t directly alter cortisol levels, at least in the short term, but does affect various other stress response systems, such as blocking ACTH action in the adrenal gland (a hormone that stimulates production of glucocorticoid steroid hormones). (7)
Just one dose of Panax ginseng showed a 132 percent increase in working capacity in a rat study published in 1988. (8) Saponins found in ginseng may affect the monoamine (neurotransmitter) levels in mice in which stress was induced, reducing the amount of noradrenalin and serotonin released as part of the stress response. (9) A 2004 lab study in the Journal of Pharmacological Sciences confirms that, in a lab, the effects of ginseng seem to be particularly motivated by their saponin content. (10)
This red ginseng also has antioxidant effects (in a lab), has been found to improve mood and mental performance in small studies, may reduce fasting blood sugar levels and may even aid newly diagnosed diabetic patients in losing weight. (11, 12)
In regards to the “cognitive-enhancing” benefits sometimes seen with Panax ginseng, a Cochrane review in 2010 found “a lack of convincing evidence” to prove it increases cognition in healthy patients, and “no high quality evidence” about its efficacy in dementia patients. (13)
Another Cochrane-style review of ginseng studies claimed its benefits were not “established beyond reasonable doubt” for “physical performance, psychomotor performance and cognitive function, immunomodulation, diabetes mellitus and herpes simplex type-II infections,” and found “promising results for improving glucose metabolism and moderating the immune response.” (14)
This review also did not rate or compile evidence on the stress-relieving qualities of Panax ginseng, although some studies on psychomotor performance attempt to encapsulate such findings. Cochrane and similarly styled reviews only examine evidence from “gold-standard” research (randomized controlled trials, or RCTs), which are lacking for Panax ginseng.
What does all this mean? For ginseng, it means that there are some initially promising results about the way this adaptogenic herb may affect stress responses in humans, but more solid research must be done to confirm the preliminary results. Anecdotal evidence including reports of individuals taking this in supplement form who claim it has helped them to focus or improved general well-being, but these should not be viewed as scientific evidence. (15)
There are a number of adaptogens referred to as ginsengs that aren’t technically ginsengs, but keep in mind that they may or may not have similar composition or effects.
2. Holy Basil
Also called tulsi, holy basil is known in India as the a powerful anti-aging supplement. Holy basil benefits have long been an integral part of Ayurvedic medicine to treat a large number of conditions, such as “infections, skin diseases, hepatic disorders, common cold and cough, malarial fever and as an antidote for snake bite and scorpion sting.” (16)
In recent years, researchers around the world have investigated the impact of holy basil on the body. Specifically, multiple studies have been conducted in mice and rats to observe its anti-stress activity.
A January 2015 study in humans tested the cognition-enhancing benefits holy basil is thought to have, and found that reaction times and error rates improved compared to placebo. (17)
One reason holy basil may be effective in improving stress response is the presence of three phytochemical compounds. The first two, ocimumosides A and B, have been identified as anti-stress compounds and may lower blood corticosterone (another stress hormone) and create positive alterations in the neurotransmitter system of the brain. (18)
There is also evidence that holy basil may help to prevent recurrence of canker sores, which are thought to be induced by stress, as well as other types of ulcers, such as gastric ulcers. (21, 22, 16)
In addition to these stress-related benefits, holy basil may potentially help to lower blood pressure, reduce seizure activity, fight bacteria, kill certain fungi, combat viral infections, protect the liver, promote immune system function and reduce pain response. (16) However, most of these have not been studied extensively and are in their infancy, as far as research goes.
Ashwagandha is often referred to as Indian ginseng. Its effects on cortisol, stress tolerance and internal stress responses have been studied for decades.
In rats and mice, ashwagandha root extract seems to stop the rise in lipid peroxidation caused by bacteria-induced stress. (23) Lipid peroxidation is the process by which oxidative stress can eventually cause cell damage within blood cells. Also in mice, ashwagandha may prevent stress-related gastric ulcers, prevent weight increase of the adrenal glands (a sign of chronic stress), help stabilize cortisol levels and aid in the non-specific stress resistance common with adaptogenic herbs. (24, 25)
It’s not just stress that ashwagandha seems to help with — reviews have noted potentially beneficial impacts on various types of tumors (cancerous and benign), cognition and memory, neurodegenerative diseases and brain health, inflammation and arthritis. (26)
You might be interested to know that ashwagandha hasn’t only been studied in animals and labs, but in humans as well. A double-blinded, randomized controlled trial (RCTs, considered the “gold standard” of research) of 64 subjects found that, “Ashwagandha root extract safely and effectively improves an individual’s resistance towards stress and thereby improves self-assessed quality of life.” (27) Another RCT in humans discovered that ashwagandha successfully regulated thyroid levels in “subclinical thyroid patients.” (28)
A case report of a 57-year-old woman published in 2012 recounted her experience in self-medicating for six months with an ashwagandha supplement to treat non-classical adrenal hyperplasia, an excess of androgen in women represented by excessive hair growth on the body, abnormal cortisol levels and male-pattern baldness. After six months, her blood levels of various stress hormones, including a form of cortisol, had decreased, and doctors noticed a reduction in the previous hair loss on the patient’s scalp. (29)
4. Astragalus root
Used in Chinese medicine, astragalus has been known to boost immunity and potentially buffer the effects of stress.
One 2005 study observed the impact of astragalus root on piglets and found that at a dose of 500 mg/kg, the adaptogen “decreased the release of inflammatory cytokine and corticosteroid [a stress hormone] and improved the lymphocyte proliferation response.” (30) Excessive inflammation and lymphocyte proliferation, or the replication of a specific type of white blood cell, are both associated with stress responses.
Astragalus root may actually temporarily increase cortisol levels to allow the body to positively respond to certain types of stress. This quick boost in temporary cortisol then lets the hormone level out as soon as the stressor has been removed. (31) Fascinatingly, this is one reason astragalus root improves the survival and healing of skin grafts in mice.
Another animal study demonstrates the ability of astragalus as an adaptogen to improve immunity and antioxidant levels. (32)
While it has not been studied extensively in human trials, a 2012 study of female athletes saw indications that astragalus improved physical performance, helped the body get rid of disease-promoting free radicals, improved the use of glucose in the bloodstream and protected the liver. (33)
5. Licorice root
Licorice root can increase energy and endurance, boost the immune system, and protect the thymus from being damaged by cortisol, but its use requires professional supervision because of how it may affect blood pressure and potassium levels. (34)
In human volunteers, supplementation with licorice root helped to regulate hormone levels associated with stress, including cortisol. (35) One potential outcome of this is the observed effect of this adaptogenic herb to help prevent ulcers. (36)
Rhodiola (rhodiola rosea), or golden root, is a potent adaptogen that has been the focus of much research. Like the other adaptogens, rhodiola provides a biological defense against stress — a study in roundworms suggests that it actually acts as a mild stressor when ingested, allowing the organism to boost its stress defenses (similar to how astragalus root works). (39) This process is known technically as “hormesis.” (40)
A human trial conducted in 2009 by scientists in Sweden tested rhodiola’s impact on people “suffering with stress-related fatigue.” They found that repeatedly administering rhodiola rosea “exerts an anti-fatigue effect that increases mental performance, particularly the ability to concentrate, and decreases cortisol response to awakening stress in burnout patients with fatigue syndrome.” (41) This demonstrates the hormesis process, this time in human subjects.
Interestingly, rhodiola may even have an impact on acute stress responses, as explained by a 2012 study in human subjects. Giving the individuals rhodiola rosea resulted in a small reduction in cortisol (tested in saliva) and a very large reduction in the acute stress caused by “intense short duration physical exercise in sedentary persons.” (42)
It has been reviewed as potentially effective for a number of issues, such as job performance, loss of appetite, sleep disturbances, irritability, high blood pressure, headaches and fatigue. (45) However, a 2012 review of rhodiola rosea found mixed results, concluding that it is possible it has positive benefits, but that the lack of well-designed, high-quality research makes it difficult to say for sure. (46)
Another review conducted in 2010 also noted the promising results of initial research, and points out that the fact rhodiola rarely interacts with medications or causes serious side effects, it’s an attractive candidate as a safe supplement. (47) This sentiment was also echoed in another 2011 review. (48)
7. Cordycep mushrooms
Cordyceps, reishi, shiitake and maitake mushrooms are fungi with antioxidant properties. That means nutrition-rich mushrooms have all the benefits of antioxidant foods. They may not be adaptogens in the classic sense, but each has adaptogenic, anti-tumor and immune-enhancing properties.
In particular, cordyceps have been observed for their impacts on cortisol levels and oxidative stress. For example, a 2006 trial involving the use of a powdered cordycep supplement found that sedentary adult males had better regulated cortisol levels after exercise-induced stress and that the supplement had anti-fatigue qualities. (49)
In mice, cordyceps helped to slightly increase the cortisol and testosterone levels in healthy male rats, giving them an edge of protection from physiological stress in a 1997 report. The same study also saw a slowing in the growth and spread of a type of lung cancer known as Lewis pneumonic cancer. (50)
Another human trial found that cortisol levels of both men and women were lower over time compared to placebo in subjects recovering from motion fatigue, a form of stress. (51)
Again, it seems that the adaptogenic effect of cordyceps involve a temporary higher boost in cortisol when exposed to stress, followed by a large drop during non-stress periods when compared with no treatment. The same was true for a three-month trial in endurance cyclists conducted in 2014, where the testosterone/cortisol ratio significantly protected the athletes from the chronic stress and related fatigue to which they often succumb. In this trial, researchers also noted that the blood of the participants confirmed an increase in antioxidant activity, quelling excessive oxidative stress. (52)
Adaptogenic herbs do have some incredible benefits, but their effects have not generally been tested long-term. My usually recommendation is to take adaptogens in six-week cycles and usually only take one at a time, to minimize any potential interactions. I would not personally take any adaptogen more than 12 weeks in any given year.
As always, you should discuss any new supplements or medications with your doctor before beginning a regimen. This is especially true with adaptogenic herbs, as several of them interact with prescription medications and are not recommended for people with certain conditions.
In particular, licorice root should never be taken except under the supervision of a physician or integrative practitioner because of the way it can impact blood pressure and potassium levels.
To touch on the subject of so-called cortisol blockers: in my experience, these are often blends of adaptogens. You don’t want to actually block cortisol, but instead give your body the ability to use it efficiently, which is why I typically don’t use such supplements.
Be sure to do your research on any supplements you are considering, and only purchase high-quality, organic varieties from trustworthy sources.
- Eating well, getting proper rest, staying active, writing down what you’re grateful for and maintaining social connection all help protect you from chronic stress, which can kill your quality of life.
- Adding adaptogens to your routine can make you even more resilient to the damaging effects of chronic stress and give your body protection against perpetually high cortisol levels.
- Seven adaptogenic herbs than can help protect you from the effects of chronic stress include Panax ginseng, holy basil, ashwagandha, astragalus root, licorice root, rhodiola rosea and cordyceps.
- Adaptogenic herbs should not be taken for long periods of time, and should only be used under the supervision of a healthcare provider.
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