How Holy Basil (Tulsi) Lowers Cortisol and Why It Matters for Rare Disease Patients

The Rare360 Editorial Team
Oct 2
4 min read

Tulsi plant beside a glass jar of powder and a wooden spoon on a table, with a cup of tea in the background.

Holy basil (Ocimum sanctum), or tulsi, is often called the “queen of herbs” in Ayurveda. For centuries, it has been used for its healing, adaptogenic, and holistic properties. Today, modern science is catching up with this ancient wisdom, with growing evidence that tulsi may lower cortisol levels - the body’s primary stress hormone. But what does that really mean for our health? And why could this be especially important for individuals living with rare diseases, who face extraordinary levels of stress in their daily lives?

What Is Cortisol and Why Should You Care?

Cortisol is a steroid hormone released by the adrenal glands as part of the hypothalamic-pituitary-adrenal (HPA) axis, which regulates your body’s response to stress. It plays a critical role in regulating metabolism, immune response, and blood sugar levels. In short bursts, cortisol is life-saving; it helps us respond to immediate threats by increasing energy availability and sharpening focus.

But when stress becomes chronic, cortisol levels can remain elevated for long periods. This “cortisol overload” is linked to serious health consequences, including:

Weakened immune function (making individuals more prone to infections)
Insulin resistance and weight gain
Sleep disturbances and fatigue
Anxiety, depression, and brain fog
Accelerated aging and inflammation-related conditions

Given this, researchers have been looking at safe, natural ways to help regulate cortisol levels. This is where holy basil comes in.

The Science Behind Holy Basil (Tulsi) and Cortisol Reduction

Several clinical and preclinical studies support tulsi’s role as an adaptogen—an agent that helps the body adapt to stress.

A 2017 randomized, double-blind, placebo-controlled study published in the Journal of Ayurveda and Integrative Medicine found that holy basil extract significantly reduced serum cortisol levels in individuals with chronic stress compared to placebo. Participants also reported improvements in sleep quality, energy levels, and mood.
Another study published in Evidence-Based Complementary and Alternative Medicine (2015) reviewed clinical trials on tulsi and concluded that it consistently showed anti-stress, anti-anxiety, and antidepressant effects.
Preclinical studies suggest that tulsi’s active compounds—such as eugenol, ursolic acid, and rosmarinic acid—help regulate the hypothalamic-pituitary-adrenal (HPA) axis, the central stress response system. These phytochemicals also exhibit antioxidant and anti-inflammatory effects, which protect the body from stress-induced cellular damage.

Taken together, these findings suggest that tulsi doesn’t just reduce cortisol—it may improve the body’s entire stress response, leading to more balanced emotional and physical health.

Why Cortisol Reduction Is Especially Relevant for Rare Disease Patients

While lowering cortisol benefits everyone, its impact could be particularly meaningful for people living with rare diseases.

Chronic Stress Burden: Rare disease patients often face what’s known as the “diagnostic odyssey”, years of medical tests, misdiagnoses, and uncertainty before receiving a correct diagnosis. This prolonged stress takes a toll on both mental and physical health, often keeping cortisol levels chronically elevated.
Healthcare System Challenges: Fragmented care, insurance battles, and limited treatment options create additional daily stressors. High cortisol levels can worsen fatigue, pain perception, and immune response, compounding the struggles already faced by this population.
Impact on Disease Progression: In certain rare diseases with autoimmune or inflammatory components, persistently high cortisol can fuel inflammation and potentially worsen disease symptoms. Finding safe ways to lower cortisol could help improve quality of life and potentially ease some disease-related complications.
Mental Health Toll: Studies show that individuals with rare diseases are at significantly higher risk of anxiety and depression. By supporting a healthier stress response, Tulsi may help reduce this mental health burden, though more targeted research is still needed.

Reducing cortisol is not just about feeling calmer; it could support immune function, improve sleep, and reduce inflammation, key factors in overall health management for rare disease patients.

What the Research Doesn’t Yet Tell Us

While Tulsi shows great promise, there are important caveats:

Limited Rare Disease Studies: Most Tulsi research involves healthy adults or individuals with general stress. Its effects in rare disease populations remain largely unexplored.
Dosing Variability: Clinical studies use different forms (leaf powder, extracts, teas) and doses of tulsi, making it hard to define a “standard” therapeutic dose.
Medication Interactions: Rare disease patients often take multiple medications. Since Tulsi can affect blood sugar and clotting, medical supervision is essential before adding it to a care plan.

That said, the adaptogenic properties of tulsi suggest it could be a promising complementary therapy—but always under medical supervision.

Practical Ways to Incorporate Tulsi

If you’re living with a rare disease or managing chronic stress, integrating holy basil supplements may help support cortisol balance and overall well-being. However, it’s critical to consult a healthcare provider before starting any new supplement, particularly because of potential drug interactions.

For those interested in trying Tulsi, here are some common approaches (with medical guidance):

Tulsi tea: Widely available and a gentle way to integrate tulsi into daily life.
Capsule or extract form: Standardized supplements used in clinical studies, though dosage should be guided by a healthcare provider.
Fresh leaves: In India, many households consume tulsi leaves directly or use them in herbal preparations.

Conclusion

Scientific research increasingly supports holy basil (Tulsi) as a natural, effective way to lower cortisol and improve stress resilience. For rare disease patients—already facing high health burdens—this herbal remedy could offer additional support in managing stress and improving quality of life. The next step lies in large-scale, targeted clinical trials that explore Tulsi’s safety and effectiveness in these communities.

Scientific research increasingly validates what Ayurveda has known for centuries—holy basil (Tulsi) can reduce cortisol and improve stress resilience. For people living with rare diseases, who often carry the heavy burden of chronic stress, this ancient herb could hold special promise as part of a holistic care approach.

Still, while early findings are encouraging, more research is needed to understand Tulsi’s full potential in rare disease populations. Until then, Tulsi can be viewed as a complementary, not substitute, therapy—one that works best when integrated thoughtfully into broader medical care.