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Holy Basil

A traditional anti-fertility agent and libido enhancer in Ayurveda, Holy Basil (also known as Tulsi) is currently being investigated for these two claims and its general health properties. A good source of dietary Ursolic acid, which may cause the anti-fertility aspects.

Our evidence-based analysis on holy basil features 26 unique references to scientific papers.

Research analysis led by and reviewed by the Examine team.
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Research Breakdown on Holy Basil

1Sources and Composition


Holy Basil, also known as Tulsi, is an Ayurvetic plant traditionally used for general health and a long life.[1] Traditionally, the active ingredient is an oil extract of the leaves, which although traditionally used for a myriad of reasons is most commonly regonized for anti-stress and pro-vitality properties.[2]

Its herbal name is Ocimum Tenuiflorum, although Ocimum Sanctum is commonly seen as a synonym; these two terms as well as Holy Basil and Tulsi are all interchangeable in regards to supplementation.


As a herbal supplement, Holy Basil contains a few molecules. These include:


2.1Stress and Anxiety

Some components of ocimum sanctum, namely ocimarin and the ocimumosides A and B, appear to exert antistress activity when given to rats at the dose of 40mg/kg.[5]

In otherwise healthy subjects given ocimum sanctum twice daily (500mg each time after meals) over the course of two months, supplementation appeared to reduce symptoms of generalized anxiety disorders as assessed by the BPRS.[7]

3Inflammation and Immunology

One human trial noted that after 4 weeks consumption of 300mg ethanolic extract of Tulsi leaves, that participants experienced an increase in some cytokines associated with the immune system; interferon-y (IFN-y), interleukin-4 (IL-4), as well as T-helper cells and NK-cells.[8] No influence on Cytotoxic T-cells or B-cells were noted in this study. When cells were isolated from subjects and pro-inflammatory chemicals were added (LPS, phytohaemagglutinin) the immune cells of the Tulsi group were more effective in mounting an adaptive immune response via IFN-y and T-helper cells and NK-cells.

These immunomodulatory effects may be secondary to the flavonoid content of Tulsi.[9]

4Interactions with Hormones


The only noted effects of Holy Basil on testosterone levels are from a rabbit study ingesting 2g of Holy Basil per day.[10] This study and previous ones[11][12] noted reductions in sperm count and reproductive potential, which parallels studies with the component of Holy Basil Ursolic Acid.[13][14]

A possible explanation being a possible androgenic analogue in Holy Basil which increases testosterone sufficiently enough to repress luteinizing and follicle-stimulating hormones significantly.[10]

5Peripheral Organ Systems


Holy Basil seems to be effective in preventing toxin-induced damage to the liver[15][16] in doses of 100-200mg/kg bodyweight. These protective effects are due to a supposed membrane stabilizing effect of Holy Basil constituents.[17]

Synergism was noted on hepatoprotection when paired with Milk Thistle.[17]

Holy Basil, like other adaptogenic compounds, can reduce cadmium build-up in the body[18] and protect the body from already placed cadmium toxicity[19] and reverse build-up.[20] The proposed mechanism was anti-oxidant flavonols also acting as metal chelators or otherwise alleviating oxidative stress of cadmium enough for other chelators to act before damage could occur.[18]

6Safety and Toxicity


Toxicity has been reported for the oil extract of Holy Basil (which contains 70+/-3% eugenol content[21]) and has been found to be 42.5ml/kg bodyweight.[22][23] Whereas the dry plant extract with a normal eugenol content has an LD50 of between 4600-6400mg/kg bodyweight in research animals.[8][2][24]


  1. ^ Singh S, Majumdar DK. Evaluation of antiinflammatory activity of fatty acids of Ocimum sanctum fixed oil. Indian J Exp Biol. (1997)
  2. ^ a b Bhargava KP, Singh N. Anti-stress activity of Ocimum sanctum Linn. Indian J Med Res. (1981)
  3. ^ a b Ursolic Acid, a Pentacyclin Triterpene, Potentiates TRAIL-induced Apoptosis through p53-independent Up-regulation of Death Receptors.
  4. ^ Prakash P, Gupta N. Therapeutic uses of Ocimum sanctum Linn (Tulsi) with a note on eugenol and its pharmacological actions: a short review. Indian J Physiol Pharmacol. (2005)
  5. ^ a b c d Gupta P, et al. Constituents of Ocimum sanctum with antistress activity. J Nat Prod. (2007)
  6. ^ Hakkim FL, Shankar CG, Girija S. Chemical composition and antioxidant property of holy basil (Ocimum sanctum L.) leaves, stems, and inflorescence and their in vitro callus cultures. J Agric Food Chem. (2007)
  7. ^ Bhattacharyya D1, et al. Controlled programmed trial of Ocimum sanctum leaf on generalized anxiety disorders. Nepal Med Coll J. (2008)
  8. ^ a b Mondal S, et al. Double-blinded randomized controlled trial for immunomodulatory effects of Tulsi (Ocimum sanctum Linn.) leaf extract on healthy volunteers. J Ethnopharmacol. (2011)
  9. ^ Mukherjee R, Dash PK, Ram GC. Immunotherapeutic potential of Ocimum sanctum (L) in bovine subclinical mastitis. Res Vet Sci. (2005)
  10. ^ a b Sethi J, et al. Effect of tulsi (Ocimum Sanctum Linn.) on sperm count and reproductive hormones in male albino rabbits. Int J Ayurveda Res. (2010)
  11. ^ Seth SD, Johri N, Sundaram KR. Antispermatogenic effect of Ocimum sanctum. Indian J Exp Biol. (1981)
  12. ^ Khanna S, Gupta SR, Grover JK. Effect of long term feeding of tulsi(Ocimum sanctum Linn) on reproductive performance of adult albino rats. Indian J Exp Biol. (1986)
  13. ^ Chattopadhyay D, et al. A potent sperm motility-inhibiting activity of bioflavonoids from an ethnomedicine of Onge, Alstonia macrophylla Wall ex A. DC, leaf extract. Contraception. (2005)
  14. ^ Ursolic acid generates symplasts in rat spermatogenic clones.
  15. ^ Ubaid RS, et al. Effect of Ocimum sanctum (OS) leaf extract on hepatotoxicity induced by antitubercular drugs in rats. Indian J Physiol Pharmacol. (2003)
  16. ^ Hepatoprotective activity of Ocimum sanctum leaf extract against paracetamol induced hepatic damage in rats.
  17. ^ a b Lahon K, Das S. Hepatoprotective activity of Ocimum sanctum alcoholic leaf extract against paracetamol-induced liver damage in Albino rats. Pharmacognosy Res. (2011)
  18. ^ a b Bharavi K, et al. Prevention of cadmium bioaccumulation by herbal adaptogens. Indian J Pharmacol. (2011)
  19. ^ Ramesh B, Satakopan VN. Antioxidant Activities of Hydroalcoholic Extract of Ocimum sanctum Against Cadmium Induced Toxicity in Rats. Indian J Clin Biochem. (2010)
  20. ^ Bharavi K, et al. Reversal of Cadmium-induced Oxidative Stress in Chicken by Herbal Adaptogens Withania Somnifera and Ocimum Sanctum. Toxicol Int. (2010)
  21. ^ Padalia RC, Verma RS. Comparative volatile oil composition of four Ocimum species from northern India. Nat Prod Res. (2011)
  22. ^ Kumar A, et al. Chemical composition, antifungal and antiaflatoxigenic activities of Ocimum sanctum L. essential oil and its safety assessment as plant based antimicrobial. Food Chem Toxicol. (2010)
  23. ^ Singh S, Taneja M, Majumdar DK. Biological activities of Ocimum sanctum L. fixed oil--an overview. Indian J Exp Biol. (2007)
  24. ^ Devi PU, Ganasoundari A. Radioprotective effect of leaf extract of Indian medicinal plant Ocimum sanctum. Indian J Exp Biol. (1995)
  25. Agrawal P, Rai V, Singh RB. Randomized placebo-controlled, single blind trial of holy basil leaves in patients with noninsulin-dependent diabetes mellitus. Int J Clin Pharmacol Ther. (1996)
  26. Bhat J, et al. In vivo enhancement of natural killer cell activity through tea fortified with Ayurvedic herbs. Phytother Res. (2010)