What Are Adaptogens? Ashwagandha, Reishi, Lion’s Mane, and the Herbs in Your Supplements

In 1947, a Soviet toxicologist named Nikolai Lazarev was trying to solve a military problem. The USSR wanted its soldiers, athletes, and cosmonauts to perform under extreme stress without breaking down. Stimulants worked short-term but burned people out. Sedatives kept them calm but useless. What Lazarev was looking for was a third category—something that would increase resistance to stress without the jittery upside of stimulants or the drowsy downside of sedatives. He called these hypothetical substances “adaptogens,” from the Latin adaptare—to adjust. The body wouldn’t be pushed up or pulled down. It would be helped to adapt.

That was almost eighty years ago. The term fell into obscurity in Western medicine, got picked up by the supplement industry in the 2010s, and is now plastered across every mushroom coffee, stress gummy, and wellness powder at your local health food store. Most of those products use the word “adaptogen” the way fast food restaurants use the word “artisan”—technically not wrong, but conveying almost nothing useful.

So let’s actually define it. Precisely. Because the word has a real scientific meaning that most of the marketing ignores.

The Actual Definition (Brekhman’s Criteria)

After Lazarev coined the term, it was his student, Israel Brekhman, who formalized the definition in the 1960s. Brekhman established three criteria that a substance must meet to qualify as an adaptogen:

1. It must be non-specific in its action. An adaptogen doesn’t target a single organ or pathway. It increases resistance to a broad range of stressors—physical, chemical, and biological.

2. It must be normalizing. This is the key distinction from stimulants and sedatives. In Brekhman’s framing, an adaptogen brings deviated physiological parameters back toward balance, whichever direction they had drifted, rather than pushing in one direction.

3. It must be non-toxic. At normal doses, an adaptogen should not cause significant side effects or disrupt normal biological functions.

These criteria sound simple, but they’re actually quite demanding. Many herbs that get called adaptogens in marketing materials don’t meet all three. Caffeine is a stimulant, not a normalizer. St. John’s Wort acts mainly on specific serotonin pathways, so it isn’t non-specific in action, and it interacts with many medications. Kava can cause liver toxicity at higher doses, failing criterion three.

The genuine adaptogens—the ones that survive Brekhman’s filter—are a smaller list than the supplement industry would have you believe, and research on most of them is still ongoing.

A Quick Look at the HPA Axis

To understand the idea behind adaptogens, it helps to know the system the term refers to. The hypothalamic-pituitary-adrenal (HPA) axis is the body’s central stress response machinery. When you encounter a stressor—a work deadline, a near-miss in traffic, an argument, even a hard workout—the hypothalamus signals the pituitary gland, which signals the adrenal glands, which release cortisol into your bloodstream. Cortisol mobilizes energy, sharpens attention, and prepares you to fight or flee.

Researchers have proposed several mechanisms by which adaptogens might interact with the body’s stress response. A review by Panossian and Wikman (2010) published in Pharmaceuticals surveys those proposals. They remain hypotheses under active study, not settled findings.

Ashwagandha: The Best-Known Adaptogen

Withania somnifera. Also called winter cherry or Indian ginseng, though it’s not related to ginseng. Used in traditional Ayurvedic practice for thousands of years and one of the most widely researched traditional adaptogens.

In our Daydream blend, ashwagandha is paired with L-theanine and Golden Teacher mushrooms.

Research status: Ongoing. Ashwagandha has been the subject of a number of studies and research continues. It can interact with some medications and is not suitable for everyone, so check with a healthcare professional first.

Reishi: The Traditional Fungus

Ganoderma lucidum. Called “the mushroom of immortality” in traditional Chinese practice, a name that reflects its roughly 2,000-year cultural reputation. Reishi isn’t a plant—it’s a fungus, a polypore mushroom that grows on hardwood trees. It is often listed among adaptogens, though that classification is debated.

Red reishi is one of the ingredients in our Sidekick capsule, alongside lion’s mane and Golden Teacher mushrooms.

Research status: Ongoing. Reishi has a long history of traditional use and continues to be studied.

Lion’s Mane: The Functional Mushroom

Hericium erinaceus. Lion’s Mane is not technically an adaptogen by the strict Brekhman criteria. It shows up in nearly every adaptogen conversation, supplement, and “adaptogenic mushroom” marketing campaign, so we need to address it honestly.

Lion’s Mane is a key ingredient in Sidekick, where it appears with Reishi and Golden Teacher mushrooms.

Research status: Ongoing. Lion’s Mane is the subject of laboratory and early-stage research.

Schisandra Berry: The Five-Flavor Berry

Schisandra chinensis. One of the fifty fundamental herbs in traditional Chinese herbalism. The Chinese name, wu wei zi, means “five-flavor berry” because it contains all five tastes recognized in Chinese herbal theory: sweet, sour, salty, bitter, and pungent. This isn’t only a charming folk detail—the berry also has a complex phytochemistry.

In traditional use, schisandra is regarded differently from settling herbs like ashwagandha and reishi, and it has a long reputation as a tonic in Chinese herbal practice. It was also studied in the Soviet era, when adaptogens attracted military funding, though much of that research was never translated or does not meet current Western trial standards.

Schisandra berry is the botanical in Brighten, which pairs it with Golden Teacher mushrooms.

Research status: Ongoing. Schisandra has a long history of traditional use, and modern research on it continues.

Ginseng: The Grandfather of Adaptogens

Panax ginseng (Asian) and Panax quinquefolius (American). One of the most widely used traditional adaptogens, with a long history in East Asian herbal practice. If adaptogens have a patriarch, ginseng is it.

Our Bloom capsule contains Siberian ginseng (Eleutherococcus senticosus, a different plant from Panax ginseng) alongside maca root, ceremonial cacao, and Golden Teacher mushrooms.

Research status: Ongoing. Ginseng has been studied extensively, with research of widely varying quality.

Rhodiola: A Soviet-Era Favorite

Rhodiola rosea. Another Soviet-era favorite, used by cosmonauts and military personnel. It is not in any current Kind Stranger product.

Research status: Ongoing.

A Note on Evidence

The supplement industry often regards every herb called an adaptogen as equivalent. They are not. Some have long traditional use, some have been studied more than others, and many have been studied only in small or early trials. Research is ongoing, and nothing here should be read as a statement about what any herb does.

When a product label says “adaptogenic blend” and lists eight herbs, the honest question is what each one is actually there for, and what the label can actually back up.

Where These Botanicals Show Up in Our Capsules

Every Kind Stranger capsule pairs Golden Teacher mushrooms with a botanical or functional mushroom. Daydream: ashwagandha and L-theanine. Sidekick: lion’s mane and red reishi. Brighten: schisandra. Holiday: passionflower. Bloom: maca, Siberian ginseng and cacao. This is a list of what each capsule contains, not a description of what it does.

The word Lazarev coined in 1947—adaptogen, from adaptare, to adjust—remains a useful window into how people have thought about stress and herbs, in Soviet laboratories and long before. Whether any given herb deserves the label is still being worked out. Herbs and mushrooms can interact with medications and are not suitable for everyone, so if you are pregnant, nursing, or take prescription medication, check with a healthcare professional first.

Where Kind Stranger Fits In

Several Kind Stranger capsules include an adaptogen or functional mushroom alongside Golden Teacher mushrooms. Daydream contains ashwagandha and L-theanine, Brighten contains schisandra, and Bloom contains Siberian ginseng, maca, and cacao. Sidekick includes lion’s mane and red reishi as functional mushrooms, and Holiday contains passionflower.

You can browse everything in the shop or start with the sample kit, and the Apothecary has more background on the ingredients. Kind Stranger does not make health or medical claims about its products.