Lavender Oil is one of the most popular oils in aromatherapy. Discover why lavender deserves its “universal” appeal.

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So, last week, Ben Greenfield asked me for the science behind lavender. He sparked me to write this article. If you found out about lavender or this article from Ben and of you want to use the exact form of lavender that Ben uses, go here.

Sometimes, you overlook the most obvious things. I’m guilty of this when I go down the rabbit holes of geeky biochemical pathways and sometimes miss the big picture. Case and point…

This just happened to me after peering through my new essential oils database. I realized I had blogged about most of my favorite essential oils. Then, to my horror, I noticed that one of the most popular oils, lavender, did not have a sufficient article worthy of its wellness wonders!

So, let’s dig deeper and dive into all things lavender now…

 

Lavender Basics

The genus Lavandula has wide origins. It roots range from the areas of the Mediterranean Sea and southern Europe, through the northern and eastern Africa and Middle Eastern countries, to southwest Asia and southeast India. There are more than 30 species of lavender as well as hundreds of hybrids and cultivars, and dozens of subspecies.

According to a 2013 article in eCAM:

The different varieties of this plant range in height from 9 inches to 3 feet, although some may grow taller with age. Lavender are divided into four main categories: L. angustifolia, commonly known as English Lavender, is a frost hardy species that has many pretty cultivars, habit, and blossom color (formerly known as L. vera or L. officinalis); L. stoechas is a large plant with greenish-grey foliage and late blooming with a very strong odor (sometimes known as French lavender); L. latifolia, a Mediterranean grass-like lavender; and L. intermedia, which is a sterile cross between L. latifolia and L. angustifolia. The various lavenders have similar ethnobotanical properties and major chemical constituents [1].1

 

A Little Walk Down Chemotype and Species Lane

For those who don’t want a lot of science, skip to the next section, Moving Beyond Chemotype, after reading the second paragraph in this section. For those that love getting their geek-on with essential oils…this is for you!

Chemotypes are variations within the same plant species that have different secondary metabolite compositions. These constituents in their specific orientation may not be found in all chemotypes of lavender or in commercially modified oils. Although many of the secondary metabolites of all lavender plants can be beneficial, Lavandula angustofolia, with high amounts of linalool and linalyl acetate, is the most researched in studies. (I’ll review this in detail in this article).

For example, in the above review on lavender, the authors stated the following regarding the main constituents of Lavandula angustifolia:

The main constituents of lavender are linalool, linalyl acetate, 1,8-cineole B-ocimene, terpinen-4-ol, and camphor. However, the relative level of each of these constituents varies in different species [1, 2]. Lavender oil, obtained from the flowers of Lavandula angustifolia (Family: Lamiaceae) by steam distillation, is chiefly composed of linalyl acetate (3,7-dimethyl-1,6-octadien-3yl acetate), linalool (3,7-dimethylocta-1,6-dien-3-ol), lavandulol, 1,8-cineole, lavandulyl acetate, and camphor. Whole lavender oil and its major components linalool and linalyl acetate are used in aromatherapy. The major components of lavender oil were identified as 51% linalyl acetate and 35% linalool measured by gas chromatography and gas chromatography-linked Fourier Transform Infrared analysis [1–3].1

 

Down the rabbit hole of chemotypes

If you really want to geek out and look at the biochemical impact of different lavender species and chemotypes read on…

In a study comparing two different species of lavender, true lavender (Lavandula angustifolia) and spike lavender (Lavandula latifolia), different constituents were found to predominant. The authors reported that mass spectrometry revealed, “Linalool (37-54?%), linalyl acetate (21-36?%) and (E)-B-caryophyllene (1-3?%) were the most abundant components for L. angustifolia. Linalool (35-51?%), eucalyptol (26-32?%), camphor (10-18?%), a-pinene (1-2?%), a-terpineol (1-2?%) and a-bisabolene (1-2?%) were the most abundant components for L. latifolia.”

A further test in the same study was done to determine the specific orientation of the molecules, known as enantiomers. Knowing this has implications on how responsive the body is to a specific constituent. The results stated that, “(S)-(-)-camphene, (R)-(+)-limonene, (1R, 9S)-(-)-(E)-B-caryophyllene and (1R, 4R, 6R, 10S)-(-)-caryophyllene oxide were found in this study as the predominant enantiomers in Spanish L. angustifolia.” This study reported that the “inhibitory activity on lipoxygenase was observed indicating a possible anti-inflammatory activity, mainly due to the linalool, camphor, p-cymene, and limonene.”2

The importance of understanding how these non-imposable mirror image molecules modulate biochemical and clinical implications is important when considering chemotypes, species, potency, quality, and safety of essential oils. For example, one study measured the effects of both R-(-) and S-(+) linalool enantiomers on various physiological parameters in 24 subjects. These included heart rate, blood pressure, electrodermal activity, and salivary cortisol. The authors reported that although both were found to be relaxing, the R-(-) linalool proved stress relieving effects, whereas, the S-(+) linalool acted on electrodermal activity, a measurement of sympathetic activity of the nervous system.

The study clearly indicated that odorants can modulate salivary cortisol levels, with both linalool enantiomers exerting relaxing effects. Concerning blood pressure and heart rate, S-(+)-linalool acted as an activating agent in contrast to electrodermal activity. R-(-)-linalool proved to be stress-relieving as determined by heart rate. In conclusion, the results revealed that (1) chirality crucially influences the physiological effects of odorants and that (2) odorants may act differently on certain physiological parameters. 3

Furthermore, in a rodent study, the different isomers of linalool and linayl acetate both demonstrated similar anti-inflammatory activity. However, at similar doses the combination of both isomers (racemate) needed a higher dose to have the same effect as the pure enantiomer. The researchers concluded, “the experimental data indicate that both the pure enantiomer and its racemate induced, after systemic administration, a reduction of edema. Moreover, the pure enantiomer, at a dose of 25 mg/kg, elicited a delayed and more prolonged effect, while the racemate form induced a significant reduction of the edema only one hour after carrageenan administration.”4

Therefore, this tells me that the “real deal” essential oils will have different effects at the cellular level than ones that are spiked with chemicals or not optimally produced.

 

Moving Beyond Chemotype

Beyond chemotype, as discussed here, the synergism and intactness of the oil is important to receive all of the biochemical, physiological, and psychological benefits. I’ve found that most of the beneficial reports for lavender and other essential oils usually correlate to the method of distillation and list the active constituents in them. In other words, oils that are tested for quality, constituents present, and purity get the best results. An example of a study that ignored theses aspects came to the conclusion that the benefit of the aroma of an essential oil (diluted in 15ml of grapeseed extract!) was mostly due to a positive expectation of it producing a result (that the effect of the aroma would have a benefit on cognition).5 This is in contrast to the studies discussed here that demonstrated that pure, therapeutic grade essential oils can exert strong biochemical shifts, beyond placebo effects.

These kinds of studies, with poor selection of therapeutic oils and experimental flaws, can give essential oils a bad rap. In fact, in a review of studies reported on Herbal Gram which evaluated lavender for anxiety, the authors noted, “The authors caution that all of the results should be considered in the context of their methodological limitations. Although there may be beneficial effects of lavender on anxiety measures, methodological issues limit the extent to which firm conclusions can be drawn.”6

Now, I’m not saying that the only Lavender oil that can be used is Lavendula angustifolia. I am saying that when researching essential oils, the therapeutic properties, which include selection of the appropriate species as well as the chemotypes, should be considered.

For example, in one study with Lavandula stoechas, the principal chemical compounds differed from Laendula angustifolia to a great extent with the authors reporting:

The principal compounds detected are: D-Fenchone (29.28%), ?-pinene (23.18%), Camphor (15.97%), Camphene (7.83%), Eucapur (3.29%), Limonene, (2.71%) Linalool, (2.01%) Endobornyl Acetate (1.03%). The essential oils also contained smaller percentages of Tricyclene, Cymene, Delta-Cadinene, Selina-3,7(11)-diene. 7

This study did find support for this lavender species as an antioxidant and blood sugar modulator in diabetic-induced rodents. Therefore, even though a different species was used, the oil constituents and quality were demonstrated.

 

Uh- Sorry Scientists, Wrong Oil!

Another consideration of essential oils and studies, as I mentioned here, is using the right oil altogether!! Using an essential oil that is known to be relaxing and has constituents that calm the nervous system may not be a suitable intervention on stress sensitive cognitive tasks. Rosemary, may be better choice. One study did report this in a comparison trail. The study was done to assess the olfactory effect of Lavandula angustifolia (lavender) and Rosmarinus officinalis (rosemary) on cognitive performance. There were 144 subjects randomly assigned to three groups (two odors or no odor) and their results on the Cognitive Drug Research computerized cognitive assessment battery was analyzed. Mood questionnaires were given prior to and after the completion of the test. The participants were “deceived” about the intention of the study to prevent expectancy effects. There was a differential performance effect, yet both oils impacted “contentedness” positively:

Analysis of performance revealed that lavender produced a significant decrement in performance of working memory, and impaired reaction times for both memory and attention based tasks compared to controls. In contrast, rosemary produced a significant enhancement of performance for overall quality of memory and secondary memory factors, but also produced an impairment of speed of memory compared to controls. With regard to mood, comparisons of the change in ratings from baseline to post-test revealed that following the completion of the cognitive assessment battery, both the control and lavender groups were significantly less alert than the rosemary condition; however, the control group was significantly less content than both rosemary and lavender conditions. These findings indicate that the olfactory properties of these essential oils can produce objective effects on cognitive performance, as well as subjective effects on mood.8

(As far as reaction time, maybe peppermint should have been added with the rosemary for speed.)

I think this study abstract below is a good summary on why poor quality studies need to be considered when deciding on the effectiveness of essential oils:

Essential oils distilled from members of the genus Lavandula have been used both cosmetically and therapeutically for centuries with the most commonly used species being L. angustifolia, L. latifolia, L. stoechas and L. x intermedia. Although there is considerable anecdotal information about the biological activity of these oils much of this has not been substantiated by scientific or clinical evidence. Among the claims made for lavender oil are that is it antibacterial, antifungal, carminative (smooth muscle relaxing), sedative, antidepressive and effective for burns and insect bites. In this review we detail the current state of knowledge about the effect of lavender oils on psychological and physiological parameters and its use as an antimicrobial agent. Although the data are still inconclusive and often controversial, there does seem to be both scientific and clinical data that support the traditional uses of lavender. However, methodological and oil identification problems have severely hampered the evaluation of the therapeutic significance of much of the research on Lavandula spp. These issues need to be resolved before we have a true picture of the biological activities of lavender essential oil.9

Thankfully, since this study, more evidence has evolved.

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The Calming and Nervous System Effects of Lavender

Ok, now on to some uses of lavender. First, there’s the calming effect…

One study tested the antioxidant effect of inhalation of lavender and rosemary essential oils in 22 subjects. The volunteers sniffed the aroma for 5 minutes and immediately following, saliva was collected. The researchers used these salivary measurements to determine free radical scavenging activity, FRSA. The researchers found that FRSA increased with low concentrations of lavender (1000 times dilution) and high concentrations of rosemary (10 times dilution). Furthermore, cortisol, the stress hormone, was also decreased in both the lavender and rosemary sniffing subjects.10 (This reminds of the two other studies I reported on with neroli, bitter orange, and clary sage that also showed a decrease of salivary cortisol with inhalation of these essential oils.)

On a clinical note… some of the same authors of this study also reported on a circadian pattern of the measurement of FRSA as well as various factors which increase (food ingestion, relaxation, inhaling a pleasant aroma, green tea) and decrease (dancing and swimming) it. They also correlated salivary patterns of FRSA to serum measurements for measuring oxidative stress.11-12 I’m bringing this up because it’s important to take into consideration that there are caveats as benefits to many types of testing and that also should be considered when assessing studies. (Will the considerations ever end!)

Back to lavender’s relaxation effects…

Lavender has a good reputation in Europe. Germany has authorized a preparation of lavender oil, Silexan, for treatment of restlessness during anxious mood.

One open-label, exploratory trial with 50 male and female patients diagnosed with neurasthenia (a type of mood condition), post-traumatic stress disorder, or somatization disorder received 80mg /day of Silexan over 6 weeks. For all patients, a decrease in their depression scale by 32.7% was seen. There was also a decrease in their symptom checklist-90 (SCL-90-R Global Severity Index) by 36.4%. Furthermore, their mental health measurement increased by 48.2% (p < 0.001). 13

A previous study also investigated the efficacy of Silexan. The study was a comparison of it to a placebo in 221 adults suffering from anxiety disorder not otherwise specified. The participants were randomized to 80 mg/day of this orally administered preparation from Lavandula species or placebo for 10 weeks. The researchers found improvements in the Hamilton Anxiety Scale (HAMA) and the Pittsburgh Sleep Quality Index (PSQI). The authors concluded:

Lavandula oil preparation had a significant beneficial influence on quality and duration of sleep and improved general mental and physical health without causing any unwanted sedative or other drug specific effects. Lavandula oil preparation silexan is both efficacious and safe for the relief of anxiety disorder not otherwise specified. It has a clinically meaningful anxiolytic effect and alleviates anxiety related disturbed sleep. 14

The reason why these two studies are important to mention, is that lavender oil had clinical benefits for mood outside of its “aromatic” use.

Still, studies do show inhalation and topical applications can be beneficial, as the study on cortisol and oxidative stress mentioned above. Here’s more evidence.

One study with 28 postpartum women with high risk of anxiety and/or depression were randomized to either to an inhalation group of essential oils or the aromatherapy hand m’technique (a method of gentle touch). Participants engaged in 15 min sessions, twice a week for four consecutive weeks. A blend of Rose otto and Lavandula angustifolia essential oils at 2% dilution was used. A control group, comprised of volunteers, were told to avoid aromatherapy use. All participants continued with allopathic care. The authors reported that midpoint and final scores of the trial indicated that aromatherapy had significant improvements in ratings for anxiety and depression.15

Finally, in a comprehensive review of the nervous system effects of lavender, the authors provided an analysis of animal and human clinical trials of lavender using different methods of applications. They indicated that lavender was shown to have effects in vivo for protecting the brain by modulating inflammatory pathways and the neurotransmitters (brain signals) dopamine, GABA and serotonin. Furthermore, human studies, demonstrated changes in the brain indicating relaxation effects through neuroimaging using functional magnetic resonance imaging (fMRI) and electroencephalography (EEG). It’s calming effects were also shown to have an impact on sleep, pain, and positive mood effects.1

 

Neuroprotective Effects in Rodents: Lavender on the Brain

Another important consideration for lavender use may be for brain health. Two studies in rodents provided support for this. One study demonstrated the antioxidant and antiapopototic activity of two chemotypes, Lavandula angustifolia spp. angustifola, considered true lavender, and Lavandula hybrid Rev. in an induced dementia model of rats. Seven continuous days of subacute exposure to the oils showed increased activity of the potent antioxidants superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) specific activities, total content of reduced glutathione (GSH), as well as reduced lipid peroxidation, as measured by malondialdehyde.

In English…the results indicated that DNA activity was kept intact in the lavender group, signifying prevention of cellular death as well as protection against cell damage in these rodent’s craniums. 16(Do rodents have different craniums?). Furthermore, the process that leads to the deterioration of lipids was decreased. This is a good thing considering the brain and all cell membranes consist of lipids.

In another study, Lavandula angustifolia (Lavender) oil was assessed for its neuroprotective effects against ischemia/reperfusion (IR) injury in mice. This means that the little rodents’ brains were deprived of circulation and revaluated after 22 hours of return of the blood supply. As you can imagine, this is a major stressor on the brain. The authors measured oxidative stress using mitochondria-generated reactive oxygen species (ROS), malondialdehyde (MDA) and carbonyl, the ratio of reduced glutathione (GSH)/glutathione disulfide (GSSG), the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in their tiny little brain tissues. They also measured damage based on histophatology (tissue changes). Regardless of the lavender being given in corn oil, and distilled for 5 hours (my eye is twitching on this poor quality and poor delivery method), the authors concluded:

In comparison with the model group, treatment with lavender oil significantly decreased neurological deficit scores, infarct size, the levels of MDA, carbonyl and ROS, and attenuated neuronal damage, upregulated SOD, CAT, GSH-Px activities and GSH/GSSG ratio. These results suggested that the neuroprotective effects of lavender oil against cerebral ischemia/reperfusion injury may be attributed to its antioxidant effects.17

Finally, a monoterpene component in lavender, linalool, was shown in yet another rat study to calm the brain by modulating the excitatory neurotransmitter glutamate. 18

 

Synergism with Essential Oils and Microbe Inhibition

Let’s talk a little about the aspect of synergism. Meaning that essential oils have the potential to act in mostly additive and synergistic ways, making them more potent against a wide range of microbes.19-23

One in vitro study demonstrated L. angustifola combined with Cinnamomum zeylanicum (cinnamon bark) or Citrus sinesis (sweet orange), “in 1?:?1 ratios, 75.6% of the essential oils investigated showed either synergistic or additive results, lending in vitro credibility to the use of essential oil blends in aroma-therapeutic practices.” 19

 

Conclusion

Based on quality studies that take into consideration the therapeutic properties of essential oils (chemotype, species, quality of the oil, methods of distillation), lavender has good evidence for mood, brain health, stress relief, calming, and immune support. I can see why it’s “universally” loved.

 

 

My Book Does Not Ignore Lavender

BreakFree Medicine

 

 

 

 

 

 

 

 

 

 

Thankfully, I didn’t ignore lavender in my new book, which is about to be released in a few weeks (click here to learn more). Speaking of lavender and my book, want a sneak peek? Click here to view it on my Saratoga.com blog. I also included two additional applications of lavender that are not discussed in this blog that I found interesting. (If you have irritated airways or mouth sores, you may want to read these study summaries!)

 

 

References:

  1. Koulivand PH, Khaleghi Ghadiri M, Gorji A. Lavender and the nervous system. Evidence-based Complementary and Alternative Medicine?: eCAM. 2013;2013:681304.
  2. Carrasco A, Martinez-Gutierrez R, Tomas V, Tudela J. Lavandula angustifolia and Lavandula latifolia Essential Oils from Spain: Aromatic Profile and Bioactivities. Planta Med. 2016 Jan;82(1-02):163-70. doi: 10.1055/s-0035-1558095. Epub 2015 Oct 5.
  3. Höferl M , Krist S , Buchbauer G Planta Medica. Chirality influences the effects of linalool on physiological parameters of stress. 2006; 72(13):1188-1192.
  4. Peana AT, D’Aquila PS, Panin F, Serra G, Pippia P, Moretti MD. Anti-inflammatory activity of linalool and linalyl acetate constituents of essential oils. Phytomedicine. 2002 Dec;9(8):721-6.
  5. Chamine I, Oken BS. Expectancy of Stress-Reducing Aromatherapy Effect and Performance on a Stress-Sensitive Cognitive Task. Evidence-based Complementary and Alternative Medicine?: eCAM. 2015;2015:419812. doi:10.1155/2015/419812.
  6. Oliff H.  Review of studies assessing the effect of lavender on anxiety. American Botanical Council. HerbalGram. August 8 2012; Herbal Clip Online:# 051254-454.
  7. Sebai H, Selmi S, Rtibi K, Souli A, Gharbi N, Sakly M. Lavender (Lavandula stoechas L.) essential oils attenuate hyperglycemia and protect against oxidative stress in alloxan-induced diabetic rats. Lipids in Health and Disease. 2013;12:189. doi:10.1186/1476-511X-12-189.
  8. Moss , Cook J, Wesnes K, Duckett P. Aromas of rosemary and lavender essential oils differentially affect cognition and mood in healthy adults. Int J Neurosci. 2003 Jan;113(1):15-38.
  9. Cavanagh HM, Wilkinson JM. Biological activities of lavender essential oil. Phytother Res. 2002 Jun;16(4):301-8.
  10. Atsumi T, Tonosaki K. Smelling lavender and rosemary increases free radical scavenging activity and decreases cortisol level in saliva. Psychiatry Res. 2007 Feb 28;150(1):89-96. Epub 2007 Feb 7.
  11. Atsumi T, Tonosaki K, Fujisawa S. Salivary free radical-scavenging activity is affected by physical and mental activities. Oral Dis. 2008 Sep;14(6):490-6. doi: 10.1111/j.1601-0825.2007.01406.x.
  12. Atsumi T, Iwakura I, Kashiwagi Y, Fujisawa S, Ueha T. Free radical scavenging activity in the nonenzymatic fraction of human saliva: a simple DPPH assay showing the effect of physical exercise. Antioxid Redox Signal. 1999 Winter;1(4):537-46.
  13. Uehleke B, Schaper S, Dienel A, Schlaefke S, Stange R. Phase II trial on the effects of Silexan in patients with neurasthenia, post-traumatic stress disorder or somatization disorder. Phytomedicine. 2012 Jun 15;19(8-9):665-71. doi: 10.1016/j.phymed.2012.02.020.
  14. Kasper S, Gastpar M, Müller WE, Volz HP, Möller HJ, Dienel A, Schläfke S.Silexan, an orally administered Lavandula oil preparation, is effective in the treatment of ‘subsyndromal’ anxiety disorder: a randomized, double-blind, placebo controlled trial. Int Clin Psychopharmacol. 2010 Sep;25(5):277-87. doi: 10.1097/YIC.0b013e32833b3242.
  15. Conrad P, Adams C. The effects of clinical aromatherapy for anxiety and depression in the high risk postpartum woman – a pilot study. Complement Ther Clin Pract. 2012 Aug;18(3):164-8. doi: 10.1016/j.ctcp.2012.05.002. Epub 2012 Jun 27.
  16. Hancianu M, Gionca O, Mihasan M, Hritcu L. Neuroprotective effects of inhaled lavender oil on scopolamine-induced dementia via anti-oxidative activities in rats. Phytomedicine. March 2013, 20(5): 446–452.
  17. Wang D, Yuan X, Liu T, Liu L, Hu Y, Wang Z, Zheng Q. Neuroprotective Activity of Lavender Oil on Transient Focal Cerebral Ischemia in Mice. Molecules. 2012, 17(8), 9803-9817; doi:10.3390/molecules17089803
  18. Elisabetsky E, Marschner J, Souza DO. Effects of Linalool on glutamatergic system in the rat cerebral cortex. Neurochem Res. 1995 Apr;20(4):461-5.
  19. De Rapper S, Kamatou G, Viljoen A, van Vuuren S. The In Vitro Antimicrobial Activity of Lavandula angustifolia Essential Oil in Combination with Other Aroma-Therapeutic Oils. Evidence-based Complementary and Alternative Medicine?: eCAM. 2013;2013:852049. doi:10.1155/2013/852049.
  20. Edwards-Jones V, Buck R, Shawcross SG, Dawson MM, Dunn K. The effect of essential oils on methicillin-resistant Staphylococcus aureus using a dressing model. Burns. 2004;30(8):772–777.
  21. Lodhia MH, Bhatt KR, Thaker VS. Antibacterial Activity of Essential Oils from Palmarosa, Evening Primrose, Lavender and Tuberose. Indian Journal of Pharmaceutical Sciences. 2009;71(2):134-136. doi:10.4103/0250-474X.54278.
  22. Edwards-Jones V, Buck R, Shawcross SG, Dawson MM, Dunn K. The effect of essential oils on methicillin-resistant Staphylococcus aureus using a dressing model. Burns. 2004 Dec;30(8):772-7.
  23. de Rapper S, Van Vuuren SF, Kamatou GP, Viljoen AM, Dagne E. The additive and synergistic antimicrobial effects of select frankincense and myrrh oils–a combination from the pharaonic pharmacopoeia. Lett Appl Microbiol. 2012 Apr;54(4):352-8. doi: 10.1111/j.1472-765X.2012.03216.x. Epub 2012 Feb 20.

Disclaimer: This information is applicable ONLY for therapeutic quality essential oils. This information DOES NOT apply to essential oils that have not been tested for purity and standardized constituents. There is no quality control in the United States, and oils labeled as “100% pure” need only to contain 5% of the actual oil. The rest of the bottle can be filled with fillers and sometimes toxic ingredients that can irritate the skin.

This material is for information purposes only and is not intended to diagnose, treat, or prescribe for any illness. You should check with your doctor regarding implementing any new strategies into your wellness regime. These statements have not been evaluated by the FDA.

Thanks Pixabay.