What Are Adaptogens?

"Adaptogen" is a word for plants (and, in marketing, some mushrooms) that are thought to help the body resist or adapt to stress. [1] It is a useful word for finding information, but it is not a guarantee. Researchers define it in different ways, no single list of adaptogens is agreed, and the human evidence differs from one ingredient to the next.

Where the term came from

• 1940. A Soviet scientist, N. Lazarev, first proposed the term while describing Schisandra chinensis and other herbs. He gave three criteria: an adaptogen is non-specific (it helps the body resist many kinds of stress), it helps maintain balance (homeostasis), and it does not harm normal body functions. [2]
• About 1950 and 1969. The Soviet scientist I. Brekhman studied ginseng and extended the idea. In 1969 he and Dardymov listed criteria for plant adaptogens, including that they must reduce the harm caused by stress states such as fatigue, infection and depression, and that, unlike traditional stimulants, their stimulating effect must not cause side effects such as insomnia. [2]

How researchers define it today

One review of the field describes adaptogens as herbs that non-specifically and non-toxically help the body resist environmental stress and keep its balance, acting through many targets in the nervous, immune and hormone systems. [2] The same review notes that "adaptogen" has generally been used as a functional term, and that other writers have sorted adaptogens into categories such as primary and secondary adaptogens. [2] In other words, the word describes a proposed function, not a regulated or medically approved class of substances.

Which ingredients are called adaptogens

There is no single accepted list. A 2026 review names Withania somnifera (ashwagandha), Panax ginseng, Rhodiola rosea, Schisandra chinensis and Eleutherococcus senticosus as prominent adaptogens. [3] NIH's complementary health center describes Asian ginseng as having been used as an adaptogen, and calls astragalus an adaptogen, a natural substance theorized to stimulate resistance to stress. [1][4] Many other ingredients are called adaptogens in marketing. See the ingredient directory for the list and the classification questions.

What the evidence looks like

• Laboratory and animal studies are promising for many ingredients, but human trials are often limited by small sizes, short durations and differences between the herbal preparations used. [3]
• NIH's evidence summaries are ingredient-specific and cautious. For ashwagandha, some preparations may be effective for insomnia and stress, evidence is unclear for anxiety, and many studies were small and used different preparations. For rhodiola, there is not enough reliable evidence to say it helps with any health purpose. For Asian ginseng, most trials were small, short, and did not agree on benefits such as fatigue. For astragalus, there is not sufficient evidence for any condition. [5][6][1][4] See Adaptogen research for the side-by-side summary.

So "adaptogens" does not mean "proven to reduce stress." What can be said depends on the specific ingredient, the preparation, the dose, the person, and the outcome measured.

Adaptogens vs stimulants

By Brekhman's definition, an adaptogen's stimulating effect should not cause insomnia the way stimulants do. [2] But insomnia is the most common side effect reported for Asian ginseng, according to NIH. [1] The definition describes an ideal, and not every ingredient matches it. If you are sensitive to stimulants, treat any herb that people call energizing as one that could affect your sleep.

Adaptogens vs nootropics and calming herbs

These labels overlap in marketing, and an ingredient can be sold under more than one. In general: an adaptogen is described by stress resistance, a nootropic is a substance marketed for thinking performance, and a calming herb is used for relaxation. None of the three terms tells you whether a product works. Judge each ingredient by the human evidence, not by the category on the label.

Herbal adaptogens vs mushrooms

Most of the adaptogen research and the NIH summaries above are about plants. Mushrooms such as reishi and cordyceps are marketed as adaptogens, and their guides, evidence and safety notes are in the Mushrooms section, so there is one guide for each.

How to read stress-response claims

• A lab marker such as cortisol is not the same as how people feel or function. Ask what was measured.
• Ask who took part, what exactly they took, for how long, and whether there was a placebo group.
• Be cautious when a claim says the ingredient "balances" hormones or "supports the adrenals." See Adrenal fatigue and "adrenal support" claims.
• Different ingredients have different cautions. See Adaptogen safety.