How Ashwagandha Lowers Cortisol and Reduces Stress

By Dr. Kevin Passero

If you frequently feel tired, anxious or unable to relax, often referred to as “wired and tired"—you’re not alone. Chronic stress has become one of the most common health challenges I see with patients in my clinics, and the body’s primary stress hormone, cortisol, is often right at the center of it.

When cortisol stays elevated for too long, it can lead to fatigue, brain fog, poor sleep, compromised immune function, weight gain and even hormone imbalances.

Fortunately, one of nature’s most trusted botanicals, ashwagandha, has been clinically shown to help bring cortisol levels back into balance—restoring calm, focus and energy naturally.

So what is ashwagandha, and how does it balance cortisol to reduce feelings of stress and anxiety? 

Ashwagandha: The Ancient Stress Regulator

Ashwagandha (Withania somnifera) is one of the most revered botanicals in Ayurvedic medicine, where it has been used for more than 3,000 years to promote vitality, resilience and calm. 

Today, modern research gives us a deeper understanding of its unique value in supporting mental clarity, steady energy, hormonal harmony and a balanced stress response. 

Ashwagandha is classified as an adaptogen—a category of herbs that help the body maintain stability and resilience under stress. Adaptogens do not push the body in one direction or another; instead, they restore equilibrium. When stress hormones spike, adaptogens help bring them down. When energy is depleted, they help rebuild.

Ashwagandha works primarily by supporting the HPA axis—the complex communication loop between the brain and adrenal glands that determines how much cortisol you produce. Chronic stress disrupts this system, causing cortisol to surge at the wrong times or remain elevated long after the stressor has passed. This can lead to symptoms like anxiety, irritability, compromised immune function, poor sleep, fatigue and “wired but tired” energy patterns.

By nourishing and normalizing HPA axis activity, ashwagandha helps the body shift out of the chronic fight-or-flight mode and into a state of restoration. 

Many of my patients describe this effect not as sedation, but as a sense of steadiness—clearer thinking, calmer moods and a feeling of being able to handle life’s challenges with a more balanced response.
 
What Are Adaptogens and How Do They Work?

Adaptogens are a unique class of plant compounds that help the body adapt to physical, emotional and environmental stressors. Think of them as thermostats for stress: instead of forcing your nervous system up or down, they help recalibrate your internal settings.

Here is what true adaptogens do:

1. Support HPA Axis Regulation
They help the hypothalamus, pituitary gland and adrenal glands communicate more effectively, which stabilizes cortisol output.

2. Promote Allostatic Balance
Allostasis is the body’s ability to maintain stability through change. Adaptogens reduce “allostatic load”—the wear and tear caused by chronic stress.

3. Protect Mitochondria and Cells from Stress Damage
Many adaptogens, including ashwagandha, provide antioxidant support that reduces oxidative stress and protects brain and nerve tissues.

4. Improve Stress Resilience Without Sedation
Unlike medications that blunt the stress response, adaptogens optimize it. Most people feel more grounded—not drowsy—and often experience improved energy and mental clarity.

This is why adaptogens have become incredibly valuable: they help normalize physiological stress patterns in a world where stress rarely lets up.

How Ashwagandha Regulates Cortisol

When stress becomes chronic, cortisol begins to function less like a helpful alarm and more like a constant flood. Elevated cortisol over time affects nearly every part of the body—sleep cycles, metabolism, thyroid function, blood sugar regulation, immune balance and mood.

Ashwagandha helps interrupt this cycle in several key ways:

1. Regulates HPA Axis Signaling
Ashwagandha improves how the brain and adrenal glands communicate. When your brain perceives stress, it signals the adrenals to release cortisol. Ashwagandha helps fine-tune this signaling so cortisol is released when you need it—but not constantly. This is one of the reasons patients often notice that they feel calmer and more mentally sharp, even within the first few weeks of taking ashwagandha.

2. Lowers Elevated Cortisol—Especially at Night
High nighttime cortisol is one of the biggest disruptors of healthy sleep. Ashwagandha has been shown in multiple human trials to help reduce evening cortisol levels, helping the body shift into a parasympathetic (“rest and digest”) state. Patients often report that they fall asleep faster, wake less frequently, and feel more restored in the morning—because cortisol rhythms begin to normalize.

3. Protects the Brain from Cortisol-Induced Stress
Ashwagandha’s bioactive compounds, known as withanolides, provide antioxidant and neuroprotective effects. Chronic stress creates inflammation and oxidative stress in the brain; withanolides help neutralize these effects, supporting memory, focus and emotional stability.

4. Reduces Physical Stress as Well as Emotional Stress
Cortisol isn’t just a mental stress hormone—it also rises during physical strain, overtraining, illness or inflammation. Ashwagandha has been shown to improve stamina, recovery and physical resilience—making it equally valuable for individuals under mental, emotional or physiological stress.

5. Clinically Proven Effects on Cortisol
Ashwagandha is one of the best-studied adaptogens, with numerous human clinical trials showing significant reductions in stress, anxiety and cortisol. In one double-blind, placebo-controlled human trial, daily supplementation with 600 mg of standardized ashwagandha extract reduced cortisol levels by 33% in just 8 weeks. Study participants also reported less anxiety, improved sleep and higher energy.

Myths and Facts About Ashwagandha and Stress

MYTH: Ashwagandha works instantly.
FACT: While some people feel calmer within days, most studies show best results after 6-8 weeks of consistent use.

MYTH: It only helps with mental stress.
FACT: Research shows ashwagandha also supports physical stress resilience improving stamina, recovery and endurance.

MYTH: It’s a sedative.
FACT: Ashwagandha doesn’t sedate—it balances. It helps quiet an overactive stress response while boosting vitality and stamina.

Choosing the Right Ashwagandha Supplement

When choosing an ashwagandha supplement, quality truly matters. That’s why I developed Durable ASHWAGANDHA®—a clinically validated, full-spectrum formula designed to help your body manage stress more effectively, restore balance to the stress response system and build long-term resilience.

Here’s what makes Durable ASHWAGANDHA superior:

Features KSM-66® Organic Ashwagandha Root Extract 
KSM-66® is the most clinically studied ashwagandha extract available today and is the only ashwagandha on the market proven in human clinical trials to be safe for long-term use. Backed by over 50 clinical trials supporting its safety and efficacy, KSM-66® is standardized for withanolide content and is clinically shown to lower cortisol levels by 33% in 8-weeks while reducing feelings of stress and anxiety, improving sleep and boosting energy.  

Full-Spectrum Root Extract (Not Leaf)
KSM-66® is made exclusively from root material—never leaves—to ensure maximum efficacy and safety. The root contains the traditional therapeutic profile used for thousands of years in Ayurvedic medicine. Some products use leaf extract, which has a different chemical balance and may cause overstimulation or unwanted side effects. 

Organic and Sustainably Grown
Choosing an organic ashwagandha, such as certified organic KSM-66® means the plants are grown without pesticides, chemical fertilizers or synthetic processing agents. This not only protects the potency and purity of the herb but also ensures a cleaner extract that’s free from environmental toxins. 

Clinically Validated Dosage
Based on the extensive clinical research, the ideal daily dose for stress and cortisol balance is 600 mg of KSM-66® ashwagandha, often split into two servings (morning and evening).

Third-Party Testing and Transparency
Each batch of Durable ASHWAGANDHA is independently tested by a third-party lab confirming potency, purity and the absence of heavy metals or contaminants.

Reduce Cortisol and Stress-Related Symptoms with Ashwagandha 

Ashwagandha is one of the most studied adaptogens in the world — and one of the few natural compounds proven in human trials to lower cortisol and reduce stress-related symptoms safely and effectively.

By supporting the HPA axis, balancing hormone output, and protecting against the long-term effects of stress, ashwagandha helps restore calm, focus and energy—without dependency or side effects.

Durable ASHWAGANDHA delivers a clinically proven 600 mg dose of organic KSM-66® Ashwagandha, along with organic Storg-C® Amla Extract. Amla’s rich vitamin C content and naturally occurring polyphenols and bioflavonoids nourish the adrenal glands, strengthens immune function, protects mitochondria and neutralizes oxidative damage driven by chronic stress.

In clinical studies, KSM-66® Ashwagandha has been shown to:
• Significantly reduce cortisol along with feelings of stress and anxiety 
• Improve mood and sleep quality
• Enhance memory and focus
• Improve energy and stamina 

To learn more about Durable ASHWAGANDHA, click here.