Adaptogens are synthetic compounds or plant extracts that may help improve the body’s response (i.e., help you “adapt”) to stress, anxiety, and fatigue. Traditionally used in Chinese and Ayurvedic medicine, these types of medicinal herbs have been making their way into mainstream grocery and health food stores in North America and elsewhere. Modern interest in adaptogens appears to have first surfaced during World War II as scientists searched for ways to improve mental and physical performance in humans during periods of stress; indeed, several studies investigating the stimulating and tonic effects of berries from the Schisandra chinensis (S. chinesis) plant, a fruit-bearing vine native to China, were published in Russian (formerly the USSR) military journals in 1945.¹ In the late 1950s, Russian scientist Nikolay Lazarev formally introduced the term adaptogen to describe compounds that could increase “the state of nonspecific resistance” in stress.¹ The study of adaptogens subsequently progressed further in Russia during the 1960s and 1970s, becoming a formal field of biomedical research geared toward developing products that could help humans maintain physical and mental performance during periods of stress.¹ 

Today, a number of commercially available compounds marketed as adaptogens exist,² but the criteria used to define a true adaptogen vary. The European Medicines Agency defines an adaptogen as 1) “almost non-toxic to the recipient”; 2) “non-specific in its pharmacological properties and acts by increasing the resistance of the organism to a broad spectrum of adverse biological, chemical, and physical factors”; 3) “a regulator having a normalizing effect on the various organ systems of the recipient organism”; and 4) having an effect that is “as pronounced as deeper are pathologic changes in the organism.”³ Other research indicates there are three categories of adaptogens—primary, secondary, and companion—based on how many criteria they meet. For example, unlike primary adaptogens, secondary adaptogens cannot influence the hypothalamic–pituitary–adrenal axis directly but do affect the immune, nervous, and endocrine systems, whereas adaptogen companions do not function as adaptogens themselves but instead work synergistically with primary and secondary adaptogens to improve their effects.⁴ In the United States, adaptogens are considered dietary supplements under the purview of the U.S. Food and Drug Administration (FDA).⁵ 

Research suggests that the stress-protective activity of adaptogens is associated with their selective reduction and enhancement of the expression levels of key mediators of the stress response common to all cells, helping to maintain or return these cells to a state of homeostasis.¹ Adaptogens can also have stimulating and tonic effects, but differ from conventional stimulants in that they don’t possess addiction, tolerance, and abuse potentials and they don’t impair mental function or lead to psychotic symptoms with long-term use.¹ 

Different adaptogens also have neuroprotective effects. Rhodiola rosea (R. rosea)—a flowering herb native to cold, high-altitude regions of Europe and Asia—has been shown to have an antidepressive effect in individuals with mild-to-moderate depression.⁶ Ashwagandha, an evergreen shrub that grows in Asia and Africa, has been shown to facilitate reductions in the Hamilton Anxiety Rating Scale and Depression, Anxiety, and Stress Scale-21 scores (scales used by physicians to measure the severity of depression and/or anxiety symptoms in their patients), as well as morning cortisol levels in stressed but otherwise healthy adults.⁷ In a multicenter U.S. trial of patients with early-stage Alzheimer’s disease,⁸ extract from Ginkgo biloba (G. biloba)—a coniferous tree native to China—showed efficacy in improving or delaying cognitive deficits. Panax ginseng (P. ginseng) extract—made from the roots of a type of ginseng native to the mountains of East Asia—demonstrated effectiveness in preventing the development of locomotor deficits in a rat model of Parkinson’s disease.⁹ 

Some adaptogens also have cardioprotective effects. A preparation of dry extracts of Aralia mandshurica—a deciduous shrub native to the mountain woodlands of Asia and North and South Amercas—P. ginseng, R. rosea, and Eleutherococcus senticosus (E. senticosus)—a small, woody shrub native to Northeastern Asia—showed therapuetic promise by reducing contractility dysfunction in heart failure and preventing irreversible cardiomyocyte damage during ischemia and reperfusion.¹⁰ Extensive research has also shown that P. ginseng can normalize blood pressure, exerting both antihypertensive and antihypotensive effects.¹¹ 

Adaptogens may also help to lessen the effects of infectious diseases. Evidence from preclinical and clinical studies reveals that different adaptogens may aid in prophylaxis and treatment of viral infections during all stages of illness, including post-infection recovery, by exerting direct antiviral effects, modulating the immune response, exhibiting anti-inflammatory activity, and repairing oxidative stress in compromised cells.¹² Indeed, along these lines, a meta-analysis of 14 studies reported that echinacea appeared to reduce the odds of developing the common cold by 58 percent,¹³ while a single study of patients with long COVID-19 reported that blood creatine levels were significantly reduced in patients who took a combination of R. rosea, E. senticosus, and S. chinensis, compared to the placebo group, suggesting a prevention of renal failure progression.¹⁴

Editor’s note: Please consult with a licensed healthcare professional before taking any herbal supplements, especially if you are already taking medication. The National Center for Complementary and Integrative Health of the U.S. National Institutes of Health has published a “Herbs at a Glance” series of fact sheets that offer information on different adaptogens, including on potential side effects, which can be found at https://www.nccih.nih.gov/health/herbsataglance.

Sources

1. Panossian A, Wikman G. Effects of adaptogens on the central nervous system and the mo-lecular mechanisms associated with their stress—protective activity. Pharmaceuticals (Basel). 2010;3(1):188–224.

2. Institute of Culinary Education. All about adaptogens: a natural gourmet center guide. https://ice.edu/blog/adaptogens-list-adaptogenic-mushrooms. Accessed 17 Sep 2022.

3. Liao L-Y, He Y-F, Li L, et al. A preliminary review of studies on adaptogens: comparison of their bioactivity in TCM with that of ginseng-like herbs used worldwide. Chin Med. 2018;13:57.

4. European Medicines Agency. Reflection paper on the adaptogenic concept. https://www.ema.europa.eu/en/documents/scientific-guideline/reflection-paper-adaptogenic-concept_en.pdf. Accessed 17 Sep 2022.

5. United States Food and Drug Administration website. FDA 101: dietary supplements. https://www.fda.gov/consumers/consumer-updates/fda-101-dietary-supplements. Accessed 17 Sep 2022.

6. Darbinyan V, Aslanyan G, Amroyan E. Clinical trial of Rhodiola rosea L. extract SHR-5 in the treatment of mild to moderate depression. Nord J Psychiatry. 2007;61(5):343–348.

7. Lopresti AL, Smith SJ, Malvi H, Kodgule R. An investigation into the stress-relieving and pharmacological actions of an ashwagandha (Withania somnifera) extract: a randomized, double-blind, placebo-controlled study. Medicine (Baltimore). 2019;98(37):e17186. 

Written by NHR Staff