SupplementScience

Adaptogens 101: What They Are, How They Work, and Which to Choose

DJP
Reviewed by , MD, Board Certified Internal Medicine

This content is for informational purposes only and does not constitute medical advice. Consult your healthcare provider before starting any supplement. Full disclaimer

TL;DR — Quick Answer

Adaptogens are a class of herbs and mushrooms that help the body resist and recover from physical, chemical, and biological stressors. They work primarily by modulating the hypothalamic-pituitary-adrenal (HPA) axis and stress mediators like cortisol and heat shock proteins. The most well-studied adaptogens are ashwagandha, rhodiola rosea, and panax ginseng.

Key Takeaways

  • Adaptogens must meet three criteria: nonspecific stress resistance, normalizing (balancing) effects, and non-toxicity
  • They work primarily by modulating the HPA axis, cortisol levels, and cellular stress proteins (Hsp70)
  • Ashwagandha is best for chronic stress and anxiety; rhodiola is best for acute energy and mental performance
  • Look for branded, standardized extracts (KSM-66, SHR-5) that match the forms used in clinical trials
  • Consult a healthcare provider before using adaptogens if you have autoimmune conditions, thyroid disorders, or take prescription medications

What Are Adaptogens?

The term "adaptogen" was coined in 1947 by Soviet toxicologist Nikolai Lazarev to describe substances that increase the body's nonspecific resistance to stress. To be classified as an adaptogen, a substance must meet three criteria established by researchers Brekhman and Dardymov in 1969:

1. **Nonspecific**: It must increase resistance to a wide range of stressors (physical, chemical, biological)

2. **Normalizing**: It must have a balancing effect, bringing overactive systems down and underactive systems up

3. **Non-toxic**: It must be safe with long-term use and not disturb normal body functions

How Adaptogens Work

Adaptogens primarily modulate the **hypothalamic-pituitary-adrenal (HPA) axis** — the body's central stress response system. When you encounter a stressor, the hypothalamus signals the pituitary gland, which signals the adrenal glands to release cortisol and adrenaline.

Adaptogens work at multiple points in this cascade:

Cortisol modulation: Adaptogens like ashwagandha reduce elevated cortisol levels without suppressing the acute cortisol response needed for immediate danger. This means they dampen chronic stress without blunting your fight-or-flight capacity.

Heat shock protein activation: Adaptogens increase expression of heat shock proteins (Hsp70), which protect cells from stress-related damage and improve stress tolerance at the cellular level.

Neurotransmitter balance: Several adaptogens influence serotonin, dopamine, and GABA pathways, contributing to mood stabilization and cognitive resilience under stress.

Major Adaptogens Compared

AdaptogenPrimary BenefitsBest ForOnsetTypical Dose
AshwagandhaCortisol reduction, anxiety relief, sleepChronic stress, anxiety, sleep4-8 weeks300-600mg (root extract)
Rhodiola roseaMental energy, fatigue resistance, focusAcute fatigue, cognitive performance30 min - hours200-600mg (SHR-5 extract)
Panax ginsengPhysical endurance, immune support, cognitionPhysical performance, immunity2-4 weeks200-400mg (standardized)
Eleutherococcus (Siberian ginseng)General vitality, immune functionDaily resilience, mild stress4-8 weeks300-400mg
Lion's maneNerve growth factor, cognitive functionBrain health, neuroprotection4-8 weeks500-3000mg
CordycepsOxygen utilization, exercise capacityAthletic performance, energy1-4 weeks1000-3000mg

Choosing the Right Adaptogen

For anxiety and sleep: Ashwagandha is the best-studied option. Look for KSM-66 or Sensoril branded extracts, which are the forms used in clinical trials.

For energy and focus: Rhodiola rosea works faster than any other adaptogen and is ideal for demanding mental work. Look for SHR-5 or WS 1375 standardized extracts.

For physical performance: Panax ginseng and cordyceps have the most evidence for exercise capacity and recovery.

For brain health: Lion's mane is unique among adaptogens for its ability to stimulate nerve growth factor (NGF), making it the top choice for long-term cognitive support.

Safety and Interactions

Adaptogens are generally safe for most adults, but important considerations include:

- **Autoimmune conditions**: Ashwagandha and ginseng can stimulate the immune system and may be inappropriate for people on immunosuppressants

- **Thyroid medications**: Ashwagandha can increase thyroid hormone levels and may interact with levothyroxine

- **Blood thinners**: Ginseng may affect platelet aggregation

- **Pregnancy**: Most adaptogens lack safety data in pregnancy and should be avoided

Always consult a healthcare provider before starting adaptogens if you take prescription medications.

Related Supplements

Frequently Asked Questions

Can I take multiple adaptogens at the same time?

Yes, adaptogens can be combined (a practice called "stacking"). Common stacks include ashwagandha + rhodiola (stress + energy), or lion's mane + cordyceps (cognition + physical performance). Start with one adaptogen for 2-4 weeks before adding another so you can assess individual effects and tolerance.

How long do adaptogens take to work?

It depends on the adaptogen. Rhodiola can produce noticeable effects within hours for acute fatigue. Ashwagandha and ginseng typically require 4-8 weeks of daily use for measurable stress and cortisol reduction. Lion's mane may take 4-8 weeks for cognitive benefits. Consistency matters more than dose for most adaptogens.

References

  1. (). Effects of adaptogens on the central nervous system and the molecular mechanisms associated with their stress-protective activity. Pharmaceuticals. DOI