What is it?
Holy basil (Ocimum sanctum) is a member of the mint, or Labiatae, family. Though it is closely related to the sweet basil (Ocimum basilicum) frequently used in cooking, holy basil has a much richer history. The plant, which is native to tropical Asia, is now found in most tropical parts of the world. It has only recently gained popularity in the United States although it has been grown in India for more than 3,000 years.1,2
Also known as “Tulsi” or “The Incomparable One,” holy basil is one of the most sacred plants in India. In Hindu mythology, Tulsi symbolizes the goddess Lakshmi, the wife of Vishnu, who is one of the religion's most important deities. The herb has been valued for centuries because of its benefits for the mind, body, and spirit.2
But while its history is deeply rooted in religion and mythology, it has also been used in several ancient systems of medicine including Ayurveda, Greek, Roman, and Siddha for thousands of years.1,2
For what health conditions can holy basil be used?
Holy basil is a powerful antioxidant with demonstrated antibacterial, antifungal, and anti-inflammatory properties.1,3 In Ayurvedic medicine, holy basil has been used to treat a variety of conditions - everything from the common cold to bronchitis to fever to certain digestive complaints, including ulcers.1,2
Although many of these treatments are still unproven by conventional testing, modern science is now taking a closer look at this fascinating herb. In the past decade, a number of scientific studies have focused on the effects of holy basil. Some investigations have shown great promise - suggesting holy basil may indeed prove effective in those customary uses. But science has even looked beyond the traditional scope, studying the herb for its therapeutic potential in cancer, specifically as an adjuvant to radiation therapy, and even for its stabilizing effects in diabetes.1,2,4,6
The most compelling data, however, suggests that holy basil possesses its greatest potential in the areas of stress relief and relaxation. And in the fast paced world in which we live, these findings may prove to be extremely significant.1,7
So, what exactly is stress? What happens to my body during stress?
Stress is a normal and natural part of everyday life. Stress occurs when the demands placed upon us exceed our body's ability to cope. The body's response to stress, often referred to as the “flight-or-fight” response, occurs automatically at these times. The adrenal glands release stress hormones, including cortisol, adrenaline and corticosterone, which give you a boost of energy and strength to “fight” or “flee.” This makes sense when faced with a physical threat, but this same response also helps you deal with a more subtle, but equally stressful psychological or emotional demand. For example, this energy boost can enhance your focus helping you to perform optimally at work or improve mental clarity allowing you to quickly deal with a conflict at home. So in this sense, some stress (and our body's response to it) is good for you - it helps us respond in emergencies. When the stressful situation has passed, the hormone levels naturally decline.
It's when stress becomes chronic, or on-going, that it can create problems. Stress hormones have other, not-so-obvious effects. They play a role in metabolism, inflammation, and immune system responses. So when our body is continually stressed, that is, continually bombarded by high levels of cortisol and corticosterone, our digestive function can become impaired - leading to increased appetite and weight gain, our nervous system can be damaged - leading to anxiety or depression, and our immune system can be suppressed - leading to sickness or even autoimmune diseases.8-10
So, while we don't want to “turn off” the stress response, we also don't want to remain in a state of continual stress. This is where holy basil comes in.
How does holy basil combat stress?
Holy basil functions as an adaptogen, enhancing the body's natural response to physical and emotional stress. Adaptogenic herbs do not alter mood, but rather, they help the body function optimally during times of stress.1,7
Multiple scientific studies examining this property of Ocimum sanctum have found that supplementation with various extracts of holy basil decrease stress hormone levels, corticosterone in particular.11-16
Lower levels of corticosterone are associated with improved mental clarity and memory, and long-term, can reduce the risk of age-related mental disorders.17
So, exactly what makes it work?
Holy basil leaves are a natural source of many important compounds that provide a wide variety of health benefits.1,2
Eugenol and caryophyllene are aromatic compounds, so named because of their pleasing fragrance or “aroma”. These compounds are present in many plants, including holy basil, and have long been used in essential oils because their fragrant scent is said to elevate both mood and spirit. Scientific studies have shown that eugenol, in particular, helps to combat stress and enhance mental clarity. Research has also shown that the triterpenoic acids isolated from holy basil effectively improve the body's response to stress.13-16
What studies support holy basil's stress-alleviating effects?
There are several studies which examine the anti-stress effects of different components of holy basil. An herbal preparation, which combined a standardized holy basil extract along with three other Ayurvedic herbs, has been shown to improve the body's ability to adapt to stress. The subjects were continually subjected to stress leading to elevated levels of stress hormones. Administration of the combination of herbs brought the hormone levels back to normal. Further testing revealed the combination also exhibited preventative effects against stress. When taken on an on-going basis, the combination reduced the level to which the hormones were raised following exposure to stressful situations.11,12
When isolated and examined individually, holy basil significantly contributed to these effects. Several studies have shown that certain alcohol extractions of holy basil combat the effects of stress. Supplementation dramatically reduced the corticosterone level, helping the body cope with stress, elevating mood, and improving mental clarity.13-15
Eugenol has been shown to possess similar effects.16
These key components of holy basil help the body respond to both physical and mental stressors, reducing the damaging effects that on-going stress can have on other aspects of health.
What should I look for in a holy basil dietary supplement?
Because multiple constituents of holy basil have been shown to combat stress, an effective supplement must provide each of these key active components at therapeutic dosages. In particular, the supplement should be standardized for eugenol, caryophyllene and triterpenoic acids, such as ursolic and oleanolic acids. As these constituents differ significantly in their chemical structure, alternate extraction methods are needed to obtain beneficial levels. It is important to look for a dietary supplement which utilizes multiple extracts of holy basil, such as alcohol extracts, supercritical (or CO2) extracts, and distillation extracts, to provide the most complete supplement.
Why are different methods of extraction important?
Different botanical extraction methods allow for the separation, isolation, and concentration of key active components naturally found in the herb. Extraction is also useful for producing a consistent product; one that will deliver the same benefits with each dose. While there are many methods for extracting botanical compounds, each will affect the herb and the key component in different ways. Certain extraction methods will isolate lipophilic (“fat-loving” or insoluble in water) components, such as triterpenoic acids, whereas other methods yield the hydrophilic (“water-loving” or water soluble) components, eugenol and caryophyllene.18,19
When both lipophilic and hydrophilic components are required for support, as is the case for holy basil, a combination of extraction methods is necessary.
So, how do the extraction methods differ?
As I mentioned, there are numerous botanical extraction methods available. Many herbs require unique extraction methods because of the complexity of the key components. I'm going to focus on three of the most common - steam distillation, alcohol extraction, and supercritical extraction. During steam distillation, the plant material is permeated with steam. As the plant tissues break down, the essential oils, key compounds, and water vapor are released, then collected and cooled. The volatile essential oil condenses and separates, and the key hydrophilic components can be easily isolated.18,20
Alcohol extraction is slightly more complex, but still one of the most frequently used methods for extracting botanical compounds. The plant constituents are fully dissolved, then purified through a distillation process. An alcohol is then applied to extract the key components from the other alcohol-insoluble plant constituents. A secondary distillation process removes the alcohol, leaving only the pure, concentrated key components.18,19,21,22
Finally, supercritical extraction, which has become increasingly popular, uses carbon dioxide (CO2) under extremely high pressure to isolate key components. The process involves low temperatures, ensuring the ingredients are not affected by high heat that could alter or weaken the beneficial compounds. Once the extraction is completed, the carbon dioxide is re-released into the atmosphere.22,24
Each of these methods can be utilized to create pure, concentrated extracts, and when these extracts are combined, they can yield a high potency dietary supplement with a broad range of activity.
Stress is linked to many aspects of both physical and mental health. Over time, stress can negatively affect the health of the digestive, immune and nervous systems. While the underlying causes of stress must be examined before one can truly heal oneself, dietary supplements can aid in the process. Holy basil, in particular, is an effective way to both prevent and combat the damaging effects of everyday stressors.
1. Gupta SK, Prakash J, Srivastava S. Validation of traditional claim of Tulsi, Ocimum sanctum Linn. as a medicinal plant. Indian J Exp Biol. 2002
2. Uma Devi P. Radioprotective, anticarcinogenic and antioxidant properties of the Indian holy basil, Ocimum sanctum (Tulasi). Indian J Exp Biol. 2001
3. Geeta, Vasudevan DM, Kedlaya R, Deepa S, Ballal M. Activity of Ocimum sanctum (the traditional Indian medicinal plant) against the enteric pathogens. Indian
J Med Sci. 2001 Aug;55(8):434-8, 472.
4. Prakash J, Gupta SK. Chemopreventive activity of Ocimum sanctum seed oil. J Ethnopharmacol. 2000 Sep;72(1-2):29-34.
5. Vrinda B, Uma Devi P. Radiation protection of human lymphocyte chromosomes in vitro by orientin and vicenin. Mutat Res. 2001 Nov 15;498(1-2):39-46.
6. 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 Sep;34(9):406-9.
7. Bhargava KP, Singh N. Anti-stress activity of Ocimum sanctum Linn. Indian J Med Res. 1981 March;73:443-451.
8. Dallman MF, Pecoraro N, Akana SF, La Fleur SE, Gomez F, Houshyar H, Bell ME, Bhatnagar S, Laugero KD, Manalo S. Chronic stress and obesity: a new view of "comfort food". Proc Natl Acad Sci U S A. 2003 Sep 30;100(20):11696-701.
9. Sapolsky R. Stress, Glucocorticoids, and Damage to the Nervous System: The Current State of Confusion. Stress. 1996 ;1:1-19.
10. Elenkov IJ, Chrousos GP. Stress hormones, proinflammatory and anti-inflammatory cytokines, and autoimmunity. Ann N Y Acad Sci. 2002 Jun;966:290-303.
11. Bhattacharya A, Muruganandam AV, Kumar V, Bhattacharya SK. Effect of poly herbal formulation, EuMil, on neurochemical perturbations induced by chronic
stress. Indian J Exp Biol. 2002 Oct;40(10):1161-3.
12. Muruganandam AV, Kumar V, Bhattacharya SK. Effect of poly herbal formulation, EuMil, on chronic stress-induced homeostatic perturbations in rats. Indian J Exp Biol. 2002 Oct;40(10):1151-60.
13. Sembulingam K, Sembulingam P, Namasivayam A. Effect of Ocimum sanctum Linn on the changes in central cholinergic system induced by acute noise stress.
J Ethnopharmacol. 2005 Jan 15;96(3):477-82.
14. Sembulingam K, Sembulingam P, Namasivayam A. Effect of Ocimum sanctum Linn on noise induced changes in plasma corticosterone level. Indian J Physiol
Pharmacol. 1997 Oct;41(4):429-30.
15. Archana R, Namasivayam A. Effect of Ocimum sanctum on noise induced changes in neutrophil functions. J Ethnopharmacol. 2000 Nov;73(1-2):81-5.
16. Sen P, Maiti PC, Puri S, Ray A, Audulov NA, Valdman AV. Mechanism of antistress activity of Ocimum sanctum Linn, eugenol and Tinospora malabarica in
experimental animals. Indian J Exp Biol. 1992 Jul;30(7):592-6.
17. Montaron MF, Drapeau E, Dupret D, Kitchener P, Aurousseau C, Le Moal M, Piazza PV, Abrous DN. Lifelong corticosterone level determines age-related decline in neurogenesis and memory. Neurobiol Aging. 2005 Jun 10.
18. Kaufman PB, Cseke LJ, Warber S, Duke JA, Brielmann HL. Bioseparation of Compounds. In: Kane H, ed. Natural Products from Plants. Boca Raton, FL: CRC
19. Cannell RJP, ed. Approaching an Isolation. In: Walker JM, ed. Methods in Biotechnology: Natural Products Isolation. Totowa, NJ: Humana Press Inc;
20. “Distillation” Wikipedia web site. Available at: http://en.wikipedia.org/wiki/Distillation. Accessed August 12, 2005.
21. Cannell RJP, ed. Product Capture: Solvent Extraction. In: Walker JM, ed. Methods in Biotechnology: Natural Products Isolation. Totowa, NJ: Humana Press Inc; 1998:59-68.
22. “Solvent Extraction” International Union of Pure and Applied Chemistry (IUPAC) web site. Available at: http://www.iupac.org/goldbook/S05752.pdf. Accessed July 28, 2005
23. Cannell RJP, ed. Supercritical Fluid Methods. In: Walker JM, ed. Methods in Biotechnology: Natural Products Isolation. Totowa, NJ: Humana Press Inc; 1998:91-109.
24. “Supercritical Fluid” Wikipedia web site. Available at: http://en.wikipedia.org/wiki/Supercritical_fluid. Accessed August 12, 2005.