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Aroma Science

How Aromatherapy Works

What is Aromatherapy?

The term Aromatherapy is really a bit of a mis-nomver, as the aroma of an essential oil is only one facet of the oil’s interaction with the human body. “Aroma” in this case means an aromatic molecule, one that is easily evaporated, and therefore detected by the nose. Aromatherapy is really the entire branch of botanical medicine that uses volatile aromatic plant compounds for the treatment of various conditions. Many actions of essential oils don’t even have to do with one’s sense of smell; beyond acting through the limbic system (the region of the brain immediately affected by smell), many essential oils show promise in the areas of: antibiotic, antiviral, antispasmodic, antifungal and other therapeutic actions. However, we’ll start with the “aroma” part – or how essential oils interact with the body’s olfactory system.

Affecting Your Gray Matter with Essential Oils

The olfactory system (your “smell” sense) is the only one of the five senses directly connected to the brain. All other senses are routed first through the thalamus, then directed to the cerebral cortex and other brain regions. Each “scent-sensing” cell is a sort of chemical receiver – they react to some scents and not others. Each of these scent-cells is directly linked to the brain by one nerve fiber. In a way, it is difficult to sense a smell and first think about it before having a response – the signal does not travel first to the thought centers. Because each scent-sensing cell is in direct contact with the chemical being sensed, and the cell is in direct contact with the brain, the physiological response to smell is quick and powerful.

The Body Response to Aromatherapy

The olfactory region of the brain is closely associated with the limbic region – the part of the brain that is regarded as being the center of emotions, memory, sex drive and intuition. The limbic system is also connected to parts of the brain that control heart rate, breathing rate, blood pressure and stress levels. Further, the olfactory region connects to the hypothalamus, which controls the entire hormonal system by influencing the pituitary. This gives us a good idea as to why the aromatic compounds of plants (the essential oils) can have an “aromatherapeutic” effect.

Beyond “Aroma”-therapy: Ways of Using Essential Oils

Aromatherapy practice also very much includes topical (skin) application and sometimes ingestion of essential oils. Safe and effective use depends completely on the particular essential oil – some are absolutely not to be taken internally, while others are strong skin irritants. Effects through topical application rely on the small-size of essential oil molecules; smaller oil-like compounds pass through the lipid bi-layers of skin cells and are absorbed into the bloodstream. Being absorbed this way, essential oils can also produce a profound physiological response. Topical application may be helpful in a variety of skin, joint, and muscle conditions, as well as for more general stress related states.

Other Diverse Applications of Aromatherapy

The actions of essential oils in Aromatherapy are as diverse as the plant species from which they come. Besides physiological responses, other “external” factors are affected. Some essential oils are believed to have extremely powerful antibiotics, antivirals, antifungals and antiparasitics; they can provide therapeutic action by fending off invaders of our own system. Tea Tree, for example, is used in many dental formulations for its gentle yet effective antibacterial action.

*Portions of this page’s content are courtesy of Zena Morris, author at Aromatherapy Answers, a leading website on aromatherapy, massage and essential oils.