Adaptogens and Scientific Research
This is part three of a five-part article series on adaptogens: Miracle Plant or Myth. If you haven’t read any of the previous parts, you can find them here: An introduction to adaptogens (part 1), Adaptogens and stress (part 2).
In this part, we will examine the research on adaptogens, both from the historical and contemporary perspectives.
As a refresher, plant adaptogens have been defined as compounds that increase the ability of an organism to adapt to environmental factors and to avoid damage from such factors (Panossian and Wagner 2005(3)).
The Adaptogenic Concept & Modern Pharmacology
The concept of one drug → one symptom or disease does not apply to adaptogens, making it difficult to relate the definition of an adaptogen to the concepts in modern pharmacology. The actions of adaptogens are described as “not disease-specific”. Adaptogens are reported to promote non-specific resistance of the body against different symptoms, diseases, and types of stress.
Scientific Research on Adaptogens
Historically, most of the research on adaptogens between the 1960s and 1980s (over 1000 articles published) happened in Russia. Even though knowledge about some of these plants dates back thousands of years to ancient Chinese and ayurvedic healing cultures, the Russian scientists studied these plants extensively. The concept adaptogen was introduced by Dr. Lazarev (a pioneering Soviet researcher) in the 1950s. Later, Israel Brekhman a Russian pharmacologist extensively studied Panax Ginseng and Eleutherococcus senticosus in the 1960s. Because these studies were published in Russian-language journals, they are relatively difficult to access.
However, starting in the 1990s, more studies began to be published outside of Russia that increased medical and scientific attention to adaptogens. In the 1990s and the 2000s, a group of scientists, comprised of Hildebert Wagner, George Wikman, and Alexander Panossian, performed and published many studies on adaptogens. Dr. Panossian, Ph.D., Dr.Sci., is the Head of R&D at the Swedish Herbal Institute and Editor-in-Chief of Phytomedicine, the International Journal of Phytotherapy and Phytopharmacology.
Numerous pre-clinical and clinical studies have been performed to prove the concept of an adaptogen. If you perform a preliminary search for adaptogens in the PubMed database, you will find hundreds of published articles on the subject. The number of studies on adaptogens has shown a steady increase over the past 10 years. And with scientific research continuously conducted more than half a century later, the concept of adaptogens has been modified and perfected.
Challenges with Scientific Research on Adaptogens
And although the concept of adaptogens is widely embraced in the herbal community, it is yet to gain recognition from mainstream pharmacology and western medicine. It is difficult to find good scientific information on adaptogens. In contrast, there is a plethora of unscientific information and baseless claims available on the internet. This makes it easy to discredit, dismiss, and undermine any validity from some existing scientific studies.
Here are two articles that summarize some misinformation available on adaptogens and products containing them. Adaptogens, the mysterious herbs that supposedly alleviate your stress, explained and Read This Before Spending Money on Adaptogens for Stress Relief (or Anything Else) These authors seek to inform readers that, while there is no shortage of adaptogenic products (drinks, creams, and elixirs) and misleading claims, there isn’t clear evidence yet that adaptogens improve well-being or cures diseases.
The problem is, viewing adaptogens as a dichotomy of either panaceas or poisons can blind us to the fact that in most cases the answer is neither. Even though many statements in the aforementioned articles are justified, I exercise caution and I invite you to do the same. Here is why.
- Don’t throw the baby out with the bathwater. The plethora of unscientific information available on the internet easily undermines the validity of some scientific studies available.
- Even after looking past the noise and unverified claims on adaptogens on the internet, there are still many challenges tied to researching the clinical efficacy of plant adaptogens. Proving their efficacy in controlled studies is complicated by many factors such as:
- Lack of standardization. Each plant is made up of many chemical compounds with varying concentrations, whereas chemical compounds synthesized in laboratories can easily be standardized.
- Plant biodiversity: Plants are by nature diverse. Even within the same plant species, there are varying ratios of active and inactive constituents.
- Quality control: The quality of the herb, meaning where it is grown, how it is harvested, stored and ultimately administered greatly contributes to its efficacy.
- Before we completely dismiss the idea of turning back to plants for its medicinal contribution, let’s not forget that plants have been an important source of pharmacologically active substances, with many drugs derived directly or indirectly from plants. Willow bark (aspirin), Penicillium mold (penicillin) Digitalis purpurea (digoxin), Atropa belladonna (Atropine), Papaver somniferum (codeine, morphine), Cinchona ledgeriana (quinine), Taxus brevifolia (Taxol), to name a few.
That being said, where can we turn to for scientific authority and consolidated research on this subject?
Governing Authorities & Position Statements
Even though there is an accepted definition for the concept of adaptogens, no internationally recognized herbal or scientific organization has come forward with an obligatory definition for the term. As a result, many supplements and products are mislabelled as adaptogenic without consequence.
Adaptogens are considered supplements in the United States, and as with all supplements, are not regulated by the Food and Drug Administration (FDA), and therefore companies making these products can’t make drug-like claims. The FDA has no officially published statement on adaptogens. In contrast, the European Medicines Agency (EMA), the equivalent of the FDA in the European Union (EU) has a committee called; The Committee on Herbal Medicinal Products (HMPC).
The HMPC is responsible for compiling and assessing scientific data on herbal substances and the preparations. Here you can find the official committee’s opinion on the concept of adaptogens, monographs, summary information for the public, assessment reports, and a summary of references for adaptogens.
The HMPC published a reflection paper on the adaptogenic concept in 2008 based on reviewing the available research articles on adaptogens and came to the following conclusions summarized below;
- The principle of an adaptogenic action needs further clarification and studies in both the pre-clinical (animal) and clinical (human) areas.
- The term “adaptogen” is considered not appropriate for marketing authorization, more clinical studies and data on the efficacy in a well-defined clinical condition would be necessary
- The concept of adaptogens is sufficient to be considered in the assessment of traditional herbal medicinal products.
The reason for this conclusion is that the clinical data (available at the time of the review) had many shortcomings such as; deficiencies in the description of inclusion and exclusion criteria and the medication, deficiencies in the diagnosis, study design, and analysis.
Even though this reflection paper was published in 2008 in service to the EU countries, from here we can begin to piece together where adaptogens stand in the scientific space.
Most Researched Adaptogens
Adaptogens are classified as primary adaptogens, secondary adaptogens and adaptogen companions in the book Adaptogens in Medical Herbalism (4)
- American ginseng root (Panax quinquefolius)
- Ashwagandha root (Withania somnifera)
- Asian ginseng root (Panax ginseng)
- Eleuthero root and leaf (Eleutherococcus senticosus)
- Rhodiola root (Rhodiola rosea)
- Schisandra seed and fruit (Schisandra chinensis)
Common secondary adaptogenic herbs (not an extensive list):
- Astragalus root (Astragalus membranaceus)
- Holy basil (Ocimum sanctum)
- Licorice root (Glycyrrhiza glabra)
- Oat seed (Avena sativa)
- Reishi mushroom (Ganoderma lucidum)
- Shatavari root (Asparagus racemosus)
- Cordyceps fungus (Cordyceps sinensis)
Of the primary adaptogens, here are the most extensively studied ones.
- Rhodiola (Rhodiola rosea)
- Schisandra (Schisandra chinensis)
- Eleuthero (Eleutherococcus senticosus)
- Panax ginseng C.A. Meyer
- Ashwagandha (Withania somnifera)
In part 4, I will present a summary of the clinical studies of these adaptogens: Rhodiola, Schisandra, Eleuthero, Panax ginseng, and Ashwagandha.
- Winston, David, and Steven Maimes. Adaptogens: Herbs for Strength, Stamina, and Stress Relief. Healing Arts Press, 2019.
- Liao, Lian-Ying, et al. “A Preliminary Review of Studies on Adaptogens: Comparison of Their Bioactivity in TCM with That of Ginseng-like Herbs Used Worldwide.” Chinese Medicine, vol. 13, no. 1, 2018, doi:10.1186/s13020-018-0214-9.
- Panossian, Alexander, and Georg Wikman. “Effects of Adaptogens on the Central Nervous System and the Molecular Mechanisms Associated with Their Stress-Protective Activity.” Pharmaceuticals (Basel, Switzerland) vol. 3,1 188-224. 19 Jan. 2010, doi:10.3390/ph3010188
- Yance, Donald R. Adaptogens in Medical Herbalism: Elite Herbs and Natural Compounds for Mastering Stress, Aging, and Chronic Disease. Healing Arts Press, 2013.