Full profile
| Also known as | Tulsi, Ocimum sanctum, Ocimum tenuiflorum |
|---|---|
| Best for | Healthy stress response support · Cortisol balance under everyday stress |
| Evidence grade | Grade B — Moderate — several human trials, some mixed results |
| Studied dose range | 125 mg twice daily, up to roughly 1200 mg/day of standardized extract. |
| Time to effect | Stress/cortisol studies generally run 6–8 weeks of daily use. |
| Best form | Standardized leaf/stem extract — Holixer or OciBest are the best-studied branded forms. |
Evidence, honestly graded
Multiple double-blind, placebo-controlled stress/cortisol RCTs exist across more than one manufacturer's standardized extract (including Holixer and OciBest), which is the specific reason this clears B rather than the single-sponsor C ceiling that applies to many adaptogens — independent replication across sponsors, not just repeated trials from one.
See the full grading rubric — study type, replication, population match, and dose adequacy — in The Evidence Standard.
427 licensed natural health products in Health Canada's LNHPD list Holy Basil as a medicinal ingredient.
That makes Holy Basil a recognized, licensable medicinal ingredient in Canada — regulated by Health Canada's Natural and Non-prescription Health Products Directorate, which issues each licensed natural health product a Natural Product Number (NPN). Search the LNHPD to verify.
Side effects
- Generally well tolerated
- Mild GI upset in some users
Who should avoid it or check first
- Pregnant or breastfeeding without clinician guidance
- Scheduled for surgery (theoretical bleeding/glucose effects)
Interactions
- Theoretical antiplatelet effect — caution with anticoagulants
- Theoretical hypoglycemic effect — caution with diabetes medication — discuss with a clinician
Stacks well with
What to look for on a label
- Specify the branded standardized extract (e.g. Holixer, OciBest), not generic "holy basil leaf."
- Use structure/function language — cortisol balance and stress response, not disease treatment.
References
- Saxena RC, Singh R, Kumar P, Negi MPS, Saxena VS, Geetharani P, Allan JJ, Venkateshwarlu K (2012). Evidence-Based Complementary and Alternative Medicine, 2012:894509Significant reduction in general-stress symptom scores versus placebo.
- Holixer (Ocimum tenuiflorum) stress/cortisol RCT. A separate randomized, double-blind, placebo-controlled trial of the Holixer extract (a different manufacturer than OciBest) in stressed adults reported lower hair cortisol and improved perceived-stress and sleep scores. PMC9524226. The two distinct manufacturers' extracts each with a placebo-controlled trial — genuine cross-sponsor replication, not repeated single-sponsor trials — is the specific basis for the B grade. Educational, not a product claim.
Grades and studied doses are our conservative reading of the human research, shown for education. They are not product claims, and a studied dose is not a recommended dose.
Revision history
Every change to this ingredient's evidence status, dated and explained. The full cross-library log lives at Evidence Updates.
- 2026-07-07New profile
Initial profile published at Grade B: stress and cortisol RCTs replicate across more than one manufacturer's standardized extract — cross-sponsor replication rather than repeated single-sponsor trials.
See how Holy Basil compares on grade, dose, and goal in the Evidence Explorer.
