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.
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Primary Information, Benefits, Effects, and Important Facts
Holy Basil (also known as Tulsi, or Ocimum sanctum) is an ayurvetic herb which has historically been used to treat a variety of general ailments. It recently has been shown to hold scientific worth in the areas of liver protection and general anti-oxidant activity, as well as being classified as an adaptogen (reducing the effects of stress on the body).
It is also used as a Testosterone Booster, although no direct evidence exists in humans for this. It has also been demonstrated to hinder reproductive capacity.
Ocimum sanctum, Green Tulsi, Sacred Basil, Tulsi, Ocimum tenuiflorum
Do Not Confuse With
Thai Basil (a table spice)
Things to Note
Many studies not using an ethanol-extract, suggesting the active ingredients may be fat-soluble in nature
Probably one of the only testosterone boosting compounds (whether it works or not) that hinders spermatogenesis, possibly related to the ursolic acid content
500mg of the leaf extract taken twice daily appears to be recommended for neurological and adaptogenic effects of holy Basil, whereas the only evidence on other health effects or testosterone boosting are done in rats with the dosages of 100-200mg/kg and 500mg/kg respectively. This leads to an estimated human dose of:
1,100-2,200mg for a 150lb person for general health and 5,500mg for testosterone boosting
1,500-2,900mg for a 200lb person for general health and 7,300mg for testosterone boosting
1,800-3,600mg for a 250lb person for general health and 9,100mg for testosterone boosting
These are estimated human dosages based on animal research, and it is unsure if they are the optimal doses for humans.
The Human Effect Matrix looks at human studies (it excludes animal and in vitro studies) to tell you what effects holy basil has on your body, and how strong these effects are.
Grade
Level of Evidence
Robust research conducted with repeated double-blind clinical trials
Multiple studies where at least two are double-blind and placebo controlled
Single double-blind study or multiple cohort studies
Uncontrolled or observational studies only
Level of Evidence
?
The amount of high quality evidence. The more evidence, the more we can trust the results.
Outcome
Magnitude of effect
?
The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.
Consistency of research results
?
Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.
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.
1.2. Composition
As a herbal supplement, Holy Basil contains a few molecules. These include:
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
4.1. Testosterone
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
5.1. Liver
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
6.1. General
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]
