There are about a million plant species, but only about 3,000 contain essential oils. Of those, 10% are used for aromatherapy commercially. And these oils are precious.

Essential oil containing plants produce their own chemical compounds to protect themselves from infection. These compounds are contained in oils that can be extracted. Since they were designed to protect the plant from microorganisms and keep the plant healthy, it makes sense that these oils tend to be both anti-microbial and anti-inflammatory.

We have the ability to use these oils for the same benefits as plants use them when we inhale their aromas. Studies have shown that when we inhale these aromas we can absorb up to 70% of their chemical compounds into our blood. The chemical compounds travel into our lungs, where they diffuse into our blood stream, furthering their potential for pharmacological activity.

Besides having a direct link to our bloodstream, aromas have a direct connection to our brain. In fact, our sense of smell is the only sense that has a direct connection to our brain (and likely, the only sense that uses quantum physics to work). When we inhale an aroma, tiny molecules that are not immediately sent to our lungs are instead dissolved into the lining of our nose. These molecules stimulate receptors in our olfactory system, which is part of our nervous system, that then carry signals directly to the limbic system in the brain.

Aromas lessen stress

The limbic system also happens to be the same part of the brain that is connected to our emotions and memories. Our feelings originate here, and they tie memories to certain scents. Because of this, when we sniff something that brings back a pleasant memory or anticipation of something pleasant, our brain automatically releases feel-good, relaxing chemica

Relaxation is one of the ways in which a smell can boost our immune system. Stress affects the nervous system, which we now know has a direct connection to both our endocrine and immune systems. When we feel stress, it increases our cortisol levels. Inhaling certain essential oils have been shown to have the ability to signal the brain to reduce stress hormones (like cortisol and adrenaline) in the body, and to naturally support the hormones and neurotransmitters associated with pleasant feelings.

According to the Journal of Frontiers in Behavioral Neuroscience, inhaling lavender essential oil works just as well as the anti-depressant Diazepam for anxiety. Because of the connection between our endocrine, immune system and nervous system (called the hypothalamic-pituitary-adrenal-axis), when we increase our stress levels, we are significantly lowering our immune system. Aromas that are able to decrease our sympathetic nervous system, which can lower heart rate, breathing rate and even our blood pressure, are, ultimately, lowering our risk of falling ill.

Aromas increase immunity

Besides lowering our stress levels, essential oils may have direct immunostimulatory properties when inhaled. Last year, Molecules Journal published an article by scientists who did a thorough review of all scientific data related to essential oils and the immune system. They found that certain essential oils, like eucalyptus and ginger, had undeniable “immune function enhancing properties” found in multiple studies

Aromas lessen inflammation

With viruses and other pathogens circulating around us, whose severity depends on how much our body induces inflammation, it may be of utmost importance to our immune system to be able to control our inflammatory response. Our body might be in a higher state of inflammation from our diet, insomnia, prior infections or diseases, toxin accumulation or dehydration. When mixed with exposure to a virus, our body may release even more inflammation in the form of hormones, called cytokines, into the blood. They are able to cross the blood-brain-barrier to activate an inflammatory response from the brain. Too much inflammation can have significant health consequence

Not surprisingly, this is where some essential oils excel. Since essential oils themselves contain biochemical molecules, they are able to exert pharmacological effects and act as anti-inflammatories. Essential oils can cross the blood-brain-barrier to reduce inflammation.

The Journal of Lipid Research reported in their January issue in 2010 that certain essential oils, like thyme and clove, reduce the expression of inflammatory COX-2 enzyme up to 75%. Anti-inflammatory drugs, like aspirin and ibuprofen, also work to block COX enzymes, however, since they are drugs, they have to be processed through the liver and kidneys, which may damage these organs over time.

With the right blend of multiple, synergistic essential oils it’s possible to stimulate the immune system, while reducing stress and inflammation with a few simple inhales.

Dr Persephone is a fully licensed herbalist and acupuncturist, Nutritional Therapist, Integrative Medicine Practitioner and Diplomat of Oriental Medicine.