In the previous post, I began my topic of specific essential oils for brain support by highlighting lavender. It is one of the most-well known for soothing and calming the mind. If you missed out on learning about the many benefits of lavender oil on the nervous system, its other positive effects, and my favorite applications, click here. (There’s also bonus material on citronella, the “summertime oil.”)
Now, I will continue with my review of essential oils with one of the “wisest” ones that has been both explored in experimental studies and verified in human subjects. First, I will do a little exploration of the compounds found in sage oil and explain how this translates to its actions in various studies. Then, we’ll look at some of the human trials using sage oil. By the time you’ve read through, I think you will agree that “sage” oil was well-named due to its impact on memory, cognition, and brain benefits.
The Essential “Sages” of the Oils: There’s More Than One Wise Plant Species in the Bottle
There are over 900 species in the genus Salvia and within the mint (Lamiacea) family. Don’t worry, I will be narrowing down the discussion to two of the most common ones in this blog, S. lavandulaefolia (Spanish Sage) and S. officinalis (Common Sage). (source, source, source)
Although they share a similar name, there are differences in the chemical makeup among these species. Furthermore, what determines the most predominant molecules in the essential oil bottle, its chemotype, are based on factors such as the plant’s sourcing, location, harvesting, environment, and more. (source, source, source)
Natural Medicines, a comprehensive review database for practitioners, reports on the essential oil of sage and the different percentages of compounds found among them as follows (bold emphasis mine):
The essential oil of sage is characterized as containing 1-2.5% monoterpenes and 3-7% tannins (72697). Thujone is a trace constituent of the essential oil of Salvia lavandulaefolia (10334). Alpha-thujone makes up 30-65% of the monoterpenes of Salvia officinalis (72697,72582). The main constituents in the essential oil of Salvia lavandulaefolia are camphor (27%), 1,8-cineole (13%), alpha- and beta-pinene (10-15%), and bornyl acetate (10%) with other minor constituents (1% or less), including geraniol, limonene, camphene, linalool, terpineol, gamma-terpinene, alpha-humulene, and beta-caryophyllene (39566,72582). The essential oil of sage has also been shown to contain perillyl alcohol. Analysis of etheric sage oil resulted in the identification of the constituents alpha-pinene, cineole, alpha- and beta-thujone, borneol, and camphor (72719). Essential oil and herb analysis has also been done by other researchers (72720,72713,72721,72722,72723,72724,72725,72726,72727,72728,72729,72578,72691,72602,72581,72730,72731,72732,72733,72707,72734,72735,72736). No additional constituents were available from these studies.
According to one review of studies, the most important active compounds in sage essential oils are deemed to be camphor, a-thujone, B-thujone, and 1-8, cineole. However, with the overwhelming “entourage” of constituents found within sage species, it may be that the sum of its parts, not the perfect percentages of its individual molecules, is what results in their shared overall brain effects.
In one in vitro study, researchers examined various combinations of the compounds present in Spanish sage to determine which ones were responsible for its role in memory enhancement. Specifically, several ratios of molecules were analyzed to assess which would have the greatest effect on preventing an enzyme from breaking down acetylcholine, acetylcholinesterase (AChE). Acetylcholine is an important neurotransmitter in the brain, and by slowing down its removal, memory can be accentuated.
The authors did indeed find that the synergy of the whole oil is what may account for its overall action. They stated, “These findings reveal that the inhibitory activity of the oil results from a complex interaction between its constituents, which produce both synergistic and antagonistic responses between the component terpenes. Understanding such interactions is important in comparing species on the basis of chemical composition.” (source)
Knowing the mechanisms in petri dishes and rodents is one thing.
The real question is, “Can sage oil prove its efficacy in human trials too?”
Thankfully, studies have shown that this complexity of knowledge of chemical interactions may not be necessary to receive the benefits of this oil on the memory and cognition in people. (source, source)
(This does not mean that quality and constituents aren’t still important)
The Impact of Sage Oils on Humans
One study highlighted how the application of Spanish sage’s mechanisms from experimental trials could carryover in the results found in a human clinical trial. After verifying Spanish sage oil’s action on acetylcholinesterase (AChE) in a lab, the authors then tested its effects on 36 humans. They found an improvement in a cognitive function test for memory after oral ingestion of .5 ml. (I’ll do the math for you later; in case you are curious.)
The abstract is included below for those who want the details:
Extracts of sage (Salvia officinalis/lavandulaefolia) with terpenoid constituents have previously been shown to inhibit cholinesterase and improve cognitive function. The current study combined an in vitro investigation of the cholinesterase inhibitory properties and phytochemical constituents of a S. lavandulaefolia essential oil, with a double-blind, placebo-controlled, balanced crossover study assessing the effects of a single dose on cognitive performance and mood. In this latter investigation 36 healthy participants received capsules containing either 50 µL of the essential oil or placebo on separate occasions, 7 days apart. Cognitive function was assessed using a selection of computerized memory and attention tasks and the Cognitive Demand Battery before the treatment and 1-h and 4-h post-dose. The essential oil was a potent inhibitor of human acetylcholinesterase (AChE) and consisted almost exclusively of monoterpenoids. Oral consumption lead to improved performance of secondary memory and attention tasks, most notably at the 1-h post-dose testing session, and reduced mental fatigue and increased alertness which were more pronounced 4-h post-dose. These results extend previous observations of improved cognitive performance and mood following AChE inhibitory sage extracts and suggest that the ability of well-tolerated terpenoid-containing extracts to beneficially modulate cholinergic function and cognitive performance deserves further attention. (source)
In a pilot study of Alzheimer’s patients, the researchers also reviewed the pharmacological activity and tolerability of Spanish sage oil. The authors reported that it produced a reduction in neuropsychiatric symptoms and an improvement in attention. The dose coincided with .05ml three times a day. (source, source) (.05ml is about 1 drop depending on thickness of an essential oil.)
Several other human studies have reported on the benefits of Spanish sage and common sage in small trials for memory, attention, and cognition. This chart details several studies from a comprehensive review.
I will go into more detail on some of the other studies, practice applications, and its validated safety in an upcoming article. Furthermore, I will discuss the implications of having essential oils that can act positively on memory for both healthy volunteers and in those struggling with neuropsychiatric disorders and dementia.
Stay tuned for more on sage oils and how they enhance the brain and mental health!
Today’s Practical Takeaways:
- Make sure you trust your manufacture to have all the synergistic compounds found in your sage essential oil bottle that have been verified in studies.
- You probably want to grab either Spanish Sage or Common Sage oil specifically for its brain benefits, so check your label!
- Feel free to enjoying diffusing this oil and inhaling it from your trusted essential oil supplier whenever you need a little “mind boost.” (As long as you’ve reviewed the safety tips below and checked with your doctor first.)
*Safety reminder: Please be extra sure to check with your doctor if you have a seizure disorder. The Epilepsy Society of the UK lists certain essential oils implicated for their antiseizure effect as well as those that have stimulating properties.
For additional safety and medical information, please be sure to visit my essential oils database. This includes a full category on how to use essential oils safely and potential drug interactions that can occur.
If you and/or your physician are interested in consulting with me to assist with supporting the integration of essential oils safely into a therapeutic protocol, essential oils consultations are available.
Are You Aware of the Super-berry, Superfood, Wolfberry?
If you are a subscriber to my essential oils’ newsletter, you are! ?
I provided a great article review and a summary I wrote myself to my subscribers. I also give the details on how this yummy fruit can be combined with essential oils. Learn more and keep up with the latest research on mood, digestion, hormones, and essential oils by signing up for my free E-newsletter below.
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. (Affiliation link.)
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. The studies are not based solely on a specific brand of an essential oil, unless stated. Please read the full study for more information.