Chronic stress, immune imbalance, and thyroid dysfunction are deeply interconnected. This forms a stress–immune–thyroid triad where each system influences the others, affecting energy, mood, and resilience. Research shows that targeted support—including adaptogens, micronutrients can help restore communication across this network. Rather than offering quick fixes, this systems-based approach addresses underlying feedback loops, combining clinical insight, patient engagement, and supportive lifestyle practices to rebuild physiological balance and improve well-being over time.
By Corey Schuler, PhD, FNP, CNS
Ocimum tenuiflorum, commonly known as holy basil or Tulsi and also known as Ociumum sanctum, has long been considered a sacred plant in Ayurveda, traditionally used to promote longevity, resilience, and spiritual clarity.* Modern science is beginning to validate some of these traditional uses, with a growing body of evidence supporting its adaptogenic, and neuroendocrine effects.* Recent clinical trials and preclinical safety assessments have spotlighted Holixer™, a standardized Ocimum tenuiflorum extract, for its ability to reduce perceived stress, improve sleep quality, and modulate stress biomarkers.* Its use may rival ashwagandha, a more well known Ayurvedic adaptogen.
Clinical Benefits: Stress Relief and Sleep Support
In a randomized, double-blind, placebo-controlled trial, 100 adults received either 250 mg per day of Holixer™ or placebo for 8 weeks. The study evaluated indices of perceived stress (PSS), sleep (AIS), and both subjective and objective markers of sleep and physiological stress response including cortisol.* Participants also underwent the Maastricht Acute Stress Test (MAST) to simulate acute stress and assess their neuroendocrine response.* [1]
Key findings:
- 37% reduction in perceived stress in the Holixer™ group (vs. 19% placebo; p = 0.003).*[1]
- 48% decrease in the AIS index (vs. 27% placebo; p = 0.025) suggesting support for sleep.*[1]
- Significant reductions in salivary cortisol, alpha-amylase, and blood pressure following acute stress exposure.*[1]
- Significantly lower hair cortisol levels, reflecting effects on hypothalamic-pituitary-adrenal (HPA)-axis activity.*[1]
- Improved sleep efficiency by 3.4% (Fitbit-based tracking), though total sleep time did not significantly differ from placebo.*[1]
These outcomes confirm the capacity of Holixer™' to mitigate both the subjective experience of stress and its objective physiological impacts, supporting its classification as a clinically effective adaptogen.*
Safety First: Preclinical Evidence
A rigorous toxicology assessment further substantiates the safety of Holixer™. This extract was evaluated using OECD-compliant protocols, including bacterial reverse mutation (Ames test), in vitro chromosomal aberration, and in vivo micronucleus assays in rodents. Additionally, an acute oral toxicity study was conducted in rats.
Safety highlights:
- No mutagenic or genotoxic effects observed up to 5000 µg/plate in vitro and 2000 mg/kg in vivo.* [2]
- Safe at oral doses up to 5000 mg/kg in rats, with no clinical signs of toxicity.*[2]
These findings reinforce the extract’s non-genotoxic, non-clastogenic, and safe oral profile, supporting its use as a dietary supplement in humans.
Mechanisms of Action: A Multi-Targeted Adaptogen
The adaptogenic effects of Ocimum tenuiflorum appear to arise from its diverse phytochemistry. Key constituents such as eugenol, ursolic acid, β-caryophyllene, ocimumosides, and rosmarinic acid modulate pathways involved in cytokine balance, free radical scavenging, and neuroendocrine regulation.*[3–6]
Mechanistically, Ocimum tenuiflorum:
• Inhibits CRH receptor-1 and 11β-HSD1, modulating HPA-axis reactivity.*[5,6]
• Reduces levels of salivary cortisol and sAA, indicating sympathetic nervous system and HPA-axis dampening.*[1]
• Enhances monoamine neurotransmission, including serotonin and dopamine.*[4]
• Supports free radical scavenging and cytokine activity, which may account for some of its activity in mood and sleep.*[3,4]
Additional Clinical and Preclinical Evidence
- Beyond Holixer™, other trials have demonstrated stress-reducing and cognitive benefits from different Ocimum tenuiflorum extracts*:
- A 6-week RCT with 1200 mg per day of O. tenuiflorum (OciBest®) showed improvements in stress-related experiences.*[7]
- In an open-label trial participants reported significant improvements in occasional anxiety and stress responses using 500 mg O. sanctum twice daily.*[8]
- Animal studies show promising potential which are now replicated in small human trials.* [6,9]
Taken together, these studies confirm the relevance of O. tenuiflorum, not just as a folk remedy, but as a scientifically supported botanical for healthy stress response.*
Conclusion: A Botanical with Modern Clinical Backing
In the face of the growing awareness of stress and sleep support needs, Ocimum tenuiflorum stands out as a safe, well-tolerated, and clinically validated adaptogen.* Holixer™, a phytochemically standardized extract, has demonstrated measurable benefits on stress perception, sleep quality, and physiological stress response in a modest daily dose of 250 mg, which makes combining it with other ingredients more practical.*
Whether used as a standalone or part of a comprehensive protocol, Ocimum tenuiflorum represents a meaningful addition to the toolkit for clinicians supporting the stress response.*
Disclaimer:
The information provided is for educational purposes only. Consult your physician or healthcare practitioner if you have specific questions before instituting any changes in your daily lifestyle including changes in diet, exercise, and supplement use.
Corey Schuler, PhD, FNP, CNS has dedicated his career to advancing the science and clinical art of integrative medicine and serves as director of medical affairs for Allergy Research Group. He is a family nurse practitioner and practices holistic primary care at Synergy Family Physicians in White Bear Lake, Minnesota.