This is my second article on how essential oils effect brain biochemistry. It is within my series on the benefits of using natural modalities to support mental health. I am currently focusing on how essential oils impact neurotransmitters since most medications for mental illness act on these brain signals.  In this way, health care practitioners and patients can make informed decisions on how supplements and essential oils can synergize, interact, or modify current treatments.

You can access review of all the previous articles, additional information, resources, and the original blog links in this article recap or this video.

Back to the Brain and Essential Oils

In my previous blog, I started to discuss an article review on the mechanisms of essential oils and their compounds for anxiety, insomnia, convulsions, pain, and cognitive issues. The focus of the authors was on how essential oils accomplish these effects at the cellular level through their interactions with various receptors.

Determining the actions of biochemical compounds can be complicated. Beyond the petri dish that looks at the cellular level, in living organisms it is more complex. Researchers often assess the “psychology” of the animal and then compare drugs with known mechanisms to the intervention to test if the response is obliterated or enhanced.

In this long summary, essential oils were reported to impact the brain signaling pathways of GABA, serotonin, opioid receptors, and other neurotransmitters. In the last post, I provided this table of mostly in vitro experiments and rodent studies that examined these mechanisms. I will review it and the full article in more depth now.

Some of my favorite highlights of essential oils and their actions as found in the table includes:

• Lemon- suppressing dopamine and accentuating serotonin
• Sage- modulating dopamine (the reward-motivation neurotransmitter)
• Lavender- impacting serotonin (equated with mood and calming)
• Bergamot- tuning synaptic connecting for better brain communication
• Bitter orange- affecting serotonin

Other ways that essential oils support brain health are also reported on in this review. An example is that coriander oil was found to increase glutathione and act as a brain antioxidant (in the hippocampus) of rats. This is similar to one of the actions of NAC.

Down to the Minute Details of An Oil’s Chemical Composition

This chart, also found within the same article, further details isolated compounds found in these oils and their main targets. You may recognize some of them:

• menthol (peppermint)
• limonene (citrus oils)
• b-pinene (fir oils- a phytoncide, frankincense)

By modifying cellular responses via receptors (i.e., sodium channels and the GABAergic system), these substances are noted to balance inhibitory and excitatory signals within the central nervous system. The authors explain how this is critical for nervous system disorders and is implicated in pain pathways, epilepsy, and anxiety.

For example, terpin-4-ol, a compound in tea tree oil, was shown to effect GABA and sodium channels resulting in an anticonvulsant effect in rodents. The effects were traced by recordings of brain electricity via an EEG (electroencelphogram).*

Understanding Biochemistry and Basis for Human Outcomes

We have so far gleaned valuable information about mechanisms and many details regarding biochemical actions of essential oils and their compounds; however, a single constituent’s properties does not fully capture the overall effect of the essential oil. The multiple effects of an oil are based on its intricate chemical makeup, as there are hundreds of compounds in one drop of an essential oil! Thankfully, this was also addressed in this review.

For example, pine oil has anti-inflammatory, antimicrobial, pain reducing, stress relieving, and sleep enhancing properties. It is suggested that the alpha pinene may be what promotes sleep through impacting GABA(a) receptors; however, all the other actions may also be calming to the brain as well. (Note the many factors linked to brain health in Box 1 of this article.)

Another important factor with examining these outcomes is that there are many caveats to petri dish and animal studies being equated to human responses. However, they do provide exploratory information. Their results can be correlated with clinical outcomes, which is a strength that the article review has as well.

I’ll give more details and specific examples within the next few articles on how essential oils can be examined based on biochemical responses of compounds, while emphasizing throughout that their actions on brain health are more than the sum of their parts.

Stay tuned.

It is my hope this information on how essential oils and their compounds can impact our brain neurotransmitters proves to be useful! Comment below!

*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.