What Are Adaptogens — and How Do They Actually Work?
- by EarthWise Natural Health
- 1 day ago
- 6 min read
If you've spent any time researching natural approaches to stress, fatigue, or hormone balance, you've almost certainly come across the word adaptogen. It's used a lot — sometimes accurately, sometimes not. In this article I want to give you a clear, clinically grounded explanation of what adaptogens are, how they work physiologically, which ones have the most evidence behind them, and how to think about using them in practice.
The term sounds modern but the concept is ancient. Herbs now classified as adaptogens have been used in Ayurvedic and Traditional Chinese Medicine for thousands of years — ashwagandha, holy basil, schisandra, and ginseng among them. What changed in the twentieth century was the attempt to define what these herbs had in common and why they worked across such a broad range of conditions.
The definition of an adaptogen — and why it matters
The term was coined by Soviet pharmacologist Nikolai Lazarev in 1947 and later developed by his colleague Israel Brekhman. An adaptogen was defined as a substance that increases non-specific resistance to stress — meaning it helps the body adapt to a wide range of stressors, whether physical, chemical, or biological, without causing harm or disrupting normal function.
Three criteria were established. The herb must be non-toxic at normal doses. It must produce a non-specific response — supporting multiple body systems rather than acting on one target. And it must help normalise physiological function regardless of the direction of the imbalance, working to bring the body back toward balance whether the system in question is overactive or underactive.
That third criterion is what makes adaptogens genuinely different from most herbs and pharmaceuticals, which typically push a system in one direction. An adaptogen is more like a regulator than a stimulant or a sedative.
How adaptogens work — the HPA axis and stress response
To understand what adaptogens are doing in the body, it helps to understand the system they're primarily working on: the HPA axis, which stands for hypothalamic-pituitary-adrenal.
When the body encounters a stressor — physical danger, emotional pressure, blood sugar instability, infection, sleep deprivation — the hypothalamus signals the pituitary gland, which signals the adrenal glands to release cortisol. Cortisol mobilises energy, sharpens alertness, and suppresses non-essential functions like digestion and immune activity. This is the stress response, and in short bursts it's entirely appropriate.
The problem comes with chronic activation. Modern life generates sustained, low-grade stress that keeps the HPA axis in a state of ongoing stimulation. Cortisol remains elevated for longer than the body is designed to sustain. Over time, the adrenal glands struggle to maintain consistent output, cortisol rhythms become dysregulated, and the downstream effects accumulate — disrupted sleep, erratic energy, poor stress tolerance, hormonal imbalance, and immune vulnerability.
Adaptogens work primarily by modulating HPA axis sensitivity. They support the body's ability to mount an appropriate stress response and — critically — to recover from it. Research on several key adaptogens has shown measurable effects on cortisol output, stress hormone regulation, and the sensitivity of cortisol receptors. The body produces less cortisol under chronic load, and the response it does produce is better calibrated to the actual demand.
The key adaptogens and what distinguishes them
Not all adaptogens work in exactly the same way, and understanding the differences helps with choosing the right one for a particular pattern.
Ashwagandha (Withania somnifera) is the most extensively researched adaptogen in Western clinical literature. Multiple randomised controlled trials have demonstrated its ability to reduce serum cortisol and subjective stress scores with consistent use. It has a particular affinity for the adrenal-cortisol axis and also demonstrates direct anxiolytic effects through interaction with GABA and serotonin pathways. In clinical practice I find it most useful where chronic stress has produced that background state of hypervigilance — nothing feels urgent but nothing fully settles either. It also has meaningful effects on thyroid function and testosterone levels in men, which speaks to its broad hormonal influence.
Holy Basil (Ocimum tenuiflorum, also known as Tulsi) works on the HPA axis with particular emphasis on blood sugar stability. Cortisol dysregulation and blood sugar dysregulation are closely linked — elevated cortisol drives glucose release, and blood sugar instability triggers further cortisol production. Holy Basil helps interrupt this cycle. It also has direct effects on mood and cognitive function, with research demonstrating reduced anxiety and improved attention with regular use. In the context of adrenal support, it's the herb I reach for when fatigue is accompanied by sugar cravings, energy crashes in the afternoon, or significant mood volatility.
Siberian Ginseng (Eleutherococcus senticosus) has a long history in Soviet research as a performance-supporting adaptogen, studied extensively in athletes, cosmonauts, and workers in demanding physical conditions. Its primary action is on physical and mental stamina — it supports the body's ability to sustain output under stress without the adrenal cost that stimulants impose. It's particularly useful for people whose depletion has a physical dimension: those who are exhausted not just mentally but in their muscles, their immune resilience, and their ability to recover after exertion.
Rhodiola (Rhodiola rosea) acts on both the HPA axis and the central nervous system, with particular research support for reducing fatigue and improving mental performance under stress. It has a faster onset than some other adaptogens — noticeable effects within days rather than weeks in many people — which makes it useful in acute periods of high demand as well as for longer-term support. There is also good evidence for its effects on burnout specifically, including improvements in energy, concentration, and sleep quality in people meeting clinical criteria for burnout syndrome.
Schisandra (Schisandra chinensis) is classified as an adaptogen but works across several body systems simultaneously — adrenal, liver, and nervous system. Its liver-protective properties make it particularly relevant where the stress load has a detoxification dimension, and its effects on mental clarity and endurance under pressure make it a useful component in formulas aimed at sustained cognitive performance.
What adaptogens won't do
This is worth being direct about, because adaptogens are sometimes marketed as solutions to problems that require more than herbal support.
Adaptogens regulate and support — they don't override. If the source of stress is structural — a work situation that is genuinely unsustainable, a sleep pattern that has been broken for years, a diet that is actively depleting — adaptogens will help the body manage the load better, but they won't remove the load. The most effective clinical outcomes I see are when herbal support sits alongside genuine lifestyle changes, not instead of them.
The other important point is timing. Adaptogens build their effects over four to twelve weeks of consistent daily use. They are tonic herbs by definition — the word tonic refers to the sustained, nourishing quality of the herb's action, as distinct from herbs that produce an immediate acute effect. People who take an adaptogen for a week and notice nothing are not failing to respond; they are simply not yet at the point in the timeline where the regulatory effects become apparent.
How I use adaptogens clinically
In formulating for adrenal and energy support, I combine adaptogens with different points of action rather than using a single herb at high dose. The rationale is that chronic stress affects multiple systems simultaneously — the HPA axis, blood sugar regulation, neurotransmitter balance, physical stamina — and a formula that addresses several of these at once produces better outcomes than one that targets only the cortisol pathway.
Adrenal Guard combines Holy Basil and Siberian Ginseng with Cinnamon and Gymnema to address the adrenal-blood sugar relationship that sustains fatigue patterns. The adaptogens support the stress response while the supporting herbs stabilise the blood sugar fluctuations that keep the adrenal system under load.
Daily Vitality takes a longer-term perspective, combining Rhodiola, Astragalus, Gotu Kola, and Schisandra to build stamina, immune resilience, and sustained cognitive clarity over time. Where Adrenal Guard is formulated for people actively managing fatigue and stress, Daily Vitality is the formula for people who want to maintain and strengthen their reserves as a daily foundation.
If you're uncertain which pattern fits your current picture, the health quiz takes about two minutes and will point you in the right direction.
Sarah Burt is a registered naturopath, medical herbalist and iridologist with 25 years of clinical experience. All EarthWise tonics are formulated by Sarah based on her clinical protocols.
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This article is for informational purposes only and is not intended to diagnose, treat or cure any health condition. Always consult a qualified health practitioner before making changes to your health regimen.
