Fresh holy basil (tulsi) leaves and herbal tea. Illustrative image.
This article is part of our Cortisol & Stress: The Complete Guide.
Holy Basil Cortisol: 3 Human Trials and What They Show
Answer first: holy basil cortisol evidence is real but thin. One 2022 randomized trial found lower hair and salivary cortisol with a standardized extract, while two older studies tracked stress symptoms, not cortisol. CortiSync lists 100 mg of holy basil leaf extract per serving. See the official CortiSync page.
Affiliate disclosure: links to CortiSync on this page are affiliate links (code 618161). We may earn a commission at no extra cost to you. This page is educational and does not diagnose, treat, cure or prevent disease.
Contents
Holy basil is a popular ingredient in stress formulas, yet most pages that mention it say only that “studies suggest” a benefit. This page reads the actual papers. We opened each abstract on PubMed or Europe PMC and report the dose, the number of people, the length and the outcome.
If you are weighing a product that contains it, the honest question is narrower than the marketing. Does holy basil cortisol research exist in humans, how strong is it, and how does the amount on a label compare with the amounts studied?
See the official CortiSync page
Holy basil cortisol: the short answer
Holy basil cortisol evidence comes down to one well-designed trial with cortisol measures, two older studies that measured symptoms, and a review that pools small studies. The signal is encouraging. The base is small, and the extracts differ.
Do not read it as proof that any holy basil product lowers cortisol. Read it as a reasonable, modestly supported ingredient in a stress routine that should still start with sleep, movement and a clinician if symptoms persist.
Holy basil cortisol: what the herb is
Holy basil, also called tulsi, is a plant from the Ayurvedic tradition. The scientific name is Ocimum tenuiflorum, and older papers use Ocimum sanctum. The 2022 trial abstract notes that Ayurveda calls it “the elixir of life”, a traditional belief rather than a proven effect.
Supplements use leaf extracts, often standardized to a marker such as ursolic acid. Because “standardized” has no legal definition for supplements, according to the NIH Office of Dietary Supplements consumer fact sheet, two bottles with the same herb can differ in what they deliver.
Holy basil cortisol: the human trials we opened
The table lists every human study of holy basil for stress that we could confirm from a PubMed or Europe PMC abstract. Only one of them measured cortisol directly.
| Study | Design | Dose used | What it measured | Main limit |
|---|---|---|---|---|
| Holixer trial, 2022 (PMID 36185698) | Randomized, double-blind, placebo-controlled, 8 weeks, 100 adults aged 18-65 | 125 mg twice daily | Perceived stress, sleep, hair and salivary cortisol, blood pressure | One branded extract; sleep tracker data not conclusive, per the authors |
| OciBest trial, 2012 (PMID 21977056) | Randomized, double-blind, placebo-controlled, 6 weeks, 79 placebo and 71 treated | 1,200 mg of actives per day | Self-rated stress symptom scores | Symptoms only; no cortisol reported in the abstract |
| Anxiety study, 2008 (PMID 19253862) | 35 people given the extract for 60 days; the abstract describes no placebo group | 500 mg twice daily | Anxiety, stress and depression rating scales | Small, no placebo arm described |
| Systematic review, 2017 (PMID 28400848) | Review of 24 human studies | Varied | Metabolic, cardiovascular, immune and neurocognitive outcomes | Authors call for work on dose and dose form |
Holy basil cortisol: the 2022 Holixer trial in detail
This is the most useful study for the cortisol question. One hundred volunteers aged 18-65 received either 125 mg of the extract twice daily or a placebo for eight weeks. The primary outcome was the Perceived Stress Scale.
Compared with placebo, the holy basil group improved more on the Perceived Stress Scale (p = 0.003) and the Athens Insomnia Scale (p = 0.025). Hair cortisol was also lower at week 8 (p = 0.025).
The researchers then exposed people to the Maastricht Acute Stress Test. The holy basil group showed lower salivary cortisol (p < 0.001), lower salivary amylase and lower blood pressure. Supplementation was well tolerated, with no major adverse effects reported.
The authors still ask for more work. Their conclusion says the sleep findings need gold-standard objective measures. It is one trial, of one extract, so replication by independent groups matters before anyone treats the result as settled.
Holy basil cortisol: what the older studies add
The 2012 OciBest study randomized 150 people to placebo or 1,200 mg of actives daily for six weeks. After six weeks, several self-rated symptoms and the total symptom score improved more with the extract. The authors reported about 39% better control of stress symptoms than placebo.
That figure comes from a self-rated symptom scale in one study. It says nothing about cortisol, and the abstract reports no adverse events. It supports the stress theme, not the hormone claim.
The 2008 anxiety study gave 500 mg twice daily to 35 people for 60 days and reported improvements in anxiety, stress and depression ratings. With no placebo group described in the abstract, it is weaker evidence than the two randomized trials.
Holy basil cortisol: what the 2017 systematic review says
A 2017 review identified 24 human studies of tulsi, covering metabolic disorders, cardiovascular disease, immunity and neurocognition. It reported favourable outcomes and no significant adverse events, and called tulsi a possible treatment for lifestyle-related conditions including psychological stress.
Read that with care. The same authors say further studies are needed to explore mechanisms, clarify dose and dose form, and find who benefits most. A review that pools small studies of different preparations cannot set a dose for you.
Holy basil cortisol: label dose versus trial dose
Label doses are daily totals. CortiSync lists its amounts per serving of two capsules, and the manufacturer directs two capsules daily with a meal. Never assume equivalence between a product and a trial extract.
| Source | Holy basil amount per day | Form | Comment |
|---|---|---|---|
| CortiSync label (read 2026-10-11) | 100 mg | Leaf extract standardized to 2% ursolic acid | One of seven ingredients |
| Holixer trial 2022 | 250 mg (125 mg twice daily) | Standardized extract | Measured hair and salivary cortisol |
| OciBest trial 2012 | 1,200 mg of actives | Extract | Symptom scores only |
| Anxiety study 2008 | 1,000 mg (500 mg twice daily) | Leaf extract | No placebo group described |
On these numbers, the CortiSync holy basil amount is lower than the amounts used in the trials we opened. That is not a verdict. A blend may rely on several ingredients, but we found no trial of the finished formula that tests it.
Holy basil cortisol: where it sits inside CortiSync
The label on the official page lists seven ingredients: Sensoril ashwagandha 300 mg, lemon balm 150 mg, lichi 120 mg, L-theanine 100 mg, holy basil 100 mg, magnolia bark 100 mg and rhodiola 50 mg per serving. Holy basil is a supporting ingredient by amount, not the lead.
The manufacturer states a 67-day guarantee and a dose of two capsules daily with a meal. Those are the brand’s statements, not our findings, and terms change. Check the current offer on the official CortiSync page.
For the other ingredients, see CortiSync ingredients research, which covers each one, and CortiSync vs ashwagandha for the lead ingredient. The Sensoril ashwagandha trials are covered separately.
Holy basil cortisol: safety and who should ask first
The trials we opened report no major adverse effects over six to eight weeks. That is reassuring but short. It says little about long-term use, pregnancy, children or drug interactions, which these abstracts do not address.
NCCIH advises telling every health care provider about the supplements you take, and notes that supplements can interact with medicines and may be untested in pregnancy and breastfeeding. As a precaution, people on blood-sugar, blood-pressure or sedative medicines should ask first, since tulsi has been studied for metabolic and cardiovascular outcomes.
Our safety guide, who should not take CortiSync, goes ingredient by ingredient, and is CortiSync safe covers the formula as a whole.
Holy basil cortisol: who it suits and who should skip it
| A reasonable fit if you | Think twice or ask a clinician if you |
|---|---|
| Want a stress-support ingredient with a small human evidence base and a short-term record | Are pregnant or breastfeeding, or planning pregnancy |
| Prefer a combined formula and accept that the blend itself is untested | Take blood-sugar, blood-pressure, sedative or other prescription medicines |
| Will pair it with sleep, exercise and a clinician check for persistent symptoms | Expect a supplement to fix a diagnosed condition or replace a cortisol test |
For testing, lifestyle and the wider picture, see do cortisol supplements work, best supplements to lower cortisol and how to reduce cortisol levels.
Holy basil cortisol: our verdict
Holy basil has a modest but genuine human record for perceived stress, with one trial that also measured cortisol. It is not the best-studied cortisol ingredient. Ashwagandha holds that position, and holy basil works best as a supporting player.
If a combined formula appeals to you, CortiSync includes holy basil alongside six other ingredients. Compare it with other options and read the PrimeGENIX CortiSync review before buying.
See the official CortiSync page
Holy Basil Cortisol: Frequently Asked Questions
Does holy basil lower cortisol?
One 2022 randomized, placebo-controlled trial of 100 adults found lower hair cortisol at week 8 and lower salivary cortisol after a lab stress test with a standardized extract. It is a single trial of one extract, so the holy basil cortisol evidence is promising but not settled.
How much holy basil should I take for stress?
There is no established dose. The trials we opened used 250 mg a day of one extract, 1,200 mg a day of actives in another, and 1,000 mg a day of leaf extract in a third. Ask a pharmacist or doctor before choosing a dose.
How long does holy basil take to work?
The trials we read ran six weeks, eight weeks and sixty days, and reported changes at the end of those periods. Nothing in the abstracts shows an effect within days, so judge any holy basil product over weeks, not hours.
Is holy basil the same as tulsi?
Yes. Tulsi is the Ayurvedic name for holy basil, and the plant appears in the literature as Ocimum tenuiflorum or Ocimum sanctum. The two Latin names are used for the same herb in the studies we opened.
Is holy basil safe?
The abstracts we opened report no major or significant adverse events in trials lasting six to eight weeks, and the 2017 review reports none in the studies it covered. Long-term safety and drug interactions were not established there, so tell your clinician about any supplement.
Holy basil or ashwagandha for cortisol?
Ashwagandha has the larger body of cortisol trials, including a 2025 meta-analysis. Holy basil has fewer trials and a smaller evidence base. Our comparison page, CortiSync vs ashwagandha, sets out the label doses and trial doses side by side.
How much holy basil is in CortiSync?
The label on the official page, read on 2026-10-11, lists 100 mg of holy basil leaf extract standardized to 2% ursolic acid per serving of two capsules. It is one of seven ingredients. We found no trial of the finished blend.
Can I take holy basil with CortiSync?
Not without asking a pharmacist or doctor. CortiSync already contains holy basil, so an extra holy basil product raises the total amount you take from the same herb and adds to the interaction questions described by NCCIH.
What does the manufacturer guarantee?
The manufacturer states a 67-day guarantee on the official page and a dose of two capsules daily with a meal. Terms and bundle bonuses change, so read the current offer on the official CortiSync page before ordering.
Reviewed By
Reviewed for ingredient accuracy and supplement-safety wording by Dr. John Carter, PharmD, clinical pharmacist and lead scientific reviewer at HealthySupplements.us. The review covers the sources and cautions cited here, not a personal recommendation for any reader.
Authority Sources We Opened
- Holy basil (Holixer) trial on stress, mood and sleep (PubMed 36185698)
- OciBest Ocimum tenuiflorum general stress study (PubMed 21977056)
- Ocimum sanctum leaf and generalized anxiety (PubMed 19253862)
- Clinical efficacy and safety of tulsi in humans: systematic review (PubMed 28400848)
- Ashwagandha, cortisol and perceived stress meta-analysis (PubMed 40746175)
- High-concentration full-spectrum ashwagandha root extract trial (PubMed 23439798)
- L-theanine and stress-related symptoms (PubMed 31623400)
- Rhodiola rosea SHR-5 and stress-related fatigue (PubMed 19016404)
- Lemon balm and mood (PubMed 12888775)
- NCCIH: Using dietary supplements wisely
- NIH Office of Dietary Supplements: Dietary supplements, consumer fact sheet
- NIH Office of Dietary Supplements: Ashwagandha fact sheet
- NCCIH: Ashwagandha
- LiverTox: Ashwagandha
