We will now review the health benefits of vetiver essential oil (Vetiveria zizanioides syn. Chrysopogon zizandioides).
Antioxidant
A study at the Genetic Resources and Biotechnology Division, Central Institute of Medicinal and Aromatic Plants, in India, reported, “The essential oil of vetiver root has been shown to possess antioxidant activity.”1 This study went on to show that vetiver roots alone showed antioxidant activity.
A “poster presentation” by Chinese scientists at Clemson University discusses “Antioxidant, Anticarcinogenic and Termiticidal Activities of Vetiver Oil.”2 A poster presentation delivers high quality science but is a different medium from either oral presentations or published papers “and should be treated accordingly.”3 The paper reported that “At the concentration of 10_l/ml, the DPPH radical scavenging effect of vetiver oil (93%) in antioxidant activity was higher than that of 1mM BHT (73%) and equivalent to 1mM tocopherol (93%).” Butylated hydroxytoleune (BHT) is a fat-soluble, organic compound derivative of phenol. It is “useful for its antioxidant properties.”4Tocopherols are derived from vegetable oils and have vitamin E activity.
This presentation tells us that vetiver oil is a better antioxidant than BHT and equal to tocopherol.
Antimicrobial/Antituberculosis
Researchers at the Department of Microbiology at the University of Western Australia took a look at 52 plant essential oils and extracts for activity against Acinetobacter baumanii, Aeromonas veronii biogroup sobria, Candida albicans, Enterococcus faecalis,Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella entericasubsp. enterica serotype typhimurium, Serratia marcescens, and Staphylococcus aureus. The test results on vetiver were quite interesting. The oils that had the lowest minimum inhibitory concentrations against the bacteria were 0.03 percent thyme oil against C. albicans and E. coli and vetiver oil at 0.008 percent against S. aureus.
The conclusion of the study was: “These results support the notion that plant essential oils and extracts may have a role as pharmaceuticals and preservatives.”5
Indian grass KHUS (Vetiveria zizanioides L. Nash) was the focus of a 2012 study from India. The researchers from the Central Institute of Medicinal and Aromatic Plants tested vetiver in an ethanolic extract as well as the spent root against Mycobacterium tuberculosis H(37)Rv and H(37)Ra strains.
The researchers concluded: “Our results suggest that ethanolic extract and hexane fraction exhibited potent antimycobacterial activity.”6 (A good study, but why didn’t they test vetiver essential oil at the same time they tested the extract?)
Treating Sleep Apnea
Abnormal pauses in breathing during sleep create a host of problems. Israel’s Weizmann Institute and the Assuta Medical Centers in Tel Aviv studied the influence of odorants on sleep respiratory patterns. Researchers used pleasant and unpleasant odorants via a small nasal mask with a regulated airflow. The study notes that “the odorant stimulus was not a puff of air but rather a block of odorant embedded within an airflow that was constant for the duration of the study.”7 Two natural odorants were used: “pleasant” undiluted lavender oil and “unpleasant” undiluted vetiver oil. Also tested were 3 percent vanillin (pleasant) and 1 percent ammonium sulfide (unpleasant).
The results of the study found that “all 4 odorants transiently decreased inhalation and increased exhalation for up to 6 breaths following the odor onset. . . . These results suggest that the olfactory system may provide a path to manipulate respiration in sleep.”
Maintaining Focus/Stimulation of Sympathetic Nerve Activity
A 2012 study in the journal Biomedical Research echoes the results of a 2001 unpublished study by Terry S. Friedman, MD, ABHM. First, we will review the 2012 study. Researchers from Kyushu University in Japan studied the effects of volatiles emitted from cut vetiver roots on humans during a visual display terminal task. Participants who breathed volatile vetiver compounds in a “low-dose condition showed faster reaction times and stimulation of sympathetic nerve activity as measured by electrocardiography. . . .
These findings indicate that volatile compounds emitted from the roots of V. zizanioides under low-dose conditions may have helped subjects to maintain performance in visual discrimination tasks while maintaining high sympathetic nerve system activity.”8 It is of interest that these effects were not observed under high-dose conditions. With some compounds, especially essential oils, a little goes a long way.
Dr. Friedmann’s study was of 16 children ages 6 to 14, previously diagnosed with Attention Deficit Hyperactivity Disorder (ADHD). None were on medication at the time of the study. Sixteen controls received no treatment.
Participants were administered the TOVA test (Test of Variables of Attention), which evaluates attention to stimuli and the degree of impulsivity, which can detect the possible presence of ADHD. The participants were also evaluated by real-time EEG, measuring their beta (13-30 cycles per second) waves, which are produced by the brain when the subject is alert or performing a task and theta waves (4-8 cycles per second), which result from a state of sleep or daydreaming while awake.
Dr. Friedmann wrote that “initially there was a difference between the waves of normal children compared to ADHD children. While brain waves from normal children were high in amounts of beta waves and low in amounts of theta waves during waking hours, the reverse was true in the children diagnosed with ADHD. In other words, ADHD children had higher amounts of theta waves as compared to beta waves.”9
The test subjects were divided into three groups and received lavender, cedarwood, or vetiver essential oil. The subjects were asked to inhale the aroma of the oil they received three times a day by holding the bottle next to the nostrils and taking three deep inhalations.
At the conclusion of 30 days, the subjects returned for retesting on the real-time EEG, where their beta-theta ratios were recorded, and they were again given the TOVA test. The control group was also tested to compare any change between their first and second TOVA test. Dr. Friedmann’s study reported that “The analyses revealed a significant improvement in the pre- and post-treatment Vetiver essential oil group. The improvement was 32%. A similar result was seen with the pre- and post-treatment of the Cedarwood essential oil group. The Lavender treated group showed no improvement between pre- and post-treatment testing. When compared with the control group, the Vetiver treated group’s improvement was statistically significant.”10
While one study in this article called the aroma of vetiver essential oil “unpleasant,” the grass root essential oil redeems itself with a number of helpful health benefits.
References
- Lugman S, et al., “Antioxidant potential of the root of Vetiveria zizanioides L. Nash.),” Indian J Biochem Biophys. 2009 Feb;46(1):122-5.
- http://www.vetiver.org/ICV3-Proceedings/USA_medicinal.pdf.
- Erren TC, Bourne PE (2007) Ten Simple Rules for a Good Poster Presentation,PLoS Comput Biol. 3(5):e102.doi:10.1371/journal.pcbi.0030102.
- http://en.wikipedia.org/wiki/Butylated_hydroxytoluene.
- Hammer KA, Carsoon CF, Riley TV, “Antimicrobial activity of essential oils and other plant extracts,” J Appl Microbiol. 1999 Jun;86(6):985-90.
- Saikia D, et al., “Anti-tuberculosis activity of Indian grass KHUS (Vetiveria zizanioides L. Nash),” Complement Ther Med. 2012 Dec;20(6):434-6.
- Arzi A, et al., “The Influence of Odorants on Respiratory Patterns in Sleep,” Chem Senses. 2010 Jan;35(1)::31-40.
- Matsubara E, et al., “Volatiles emitted from the roots of Vetiveria zizanioidessuppress the decline in attention during a visual display task,” Biomed Res.2012:33(5):299-308.
- A PDF of Dr. Friedmann’s study can be found at:http://aromatherapyliving.com/docs/ADHD_Research_by_Dr_Terry_Friedmann.pdf.
- Ibid.