What are Essential Oils?
Aromatic plants have been used in traditional medicine for thousands of years in numerous forms, from the freshly harvested raw plant and its natural secretions to extracts and distillation products.
Essential oils are extracted from the leaves, flowers, stems, or roots, and they contain the characteristic odor of the plant from which they were obtained.
For example, we all consume essential oils when we eat food. Pecans, almonds, olives, figs, tomatoes, carrots, cabbage, mangoes, peaches, butter, coffee, cinnamon and peppermint naturally contain essential oils.
Fresh aromatic plants typically contain 1-2% by weight of mainly fragrant volatile compounds. When isolated by distillation as essential oils, the increased concentration of these constituents means that any biological properties are much more evident. Some of these properties may offer therapeutic benefits, but some may manifest as toxicity.
Many of the single constituents found in essential oils are used by insects for communication. Though much more complex in plants, they fulfill a similar function – communication – generally as attractants to insects, occasionally a message to other plants of the same genus. They also act as protectors against fungi, bacteria and other predators, play an important role in attracting pollinators, and prevent other plants from growing in their territory.
All these functions require volatility, therefore these are also known as volatile oils. The word “essential” is used to reflect the intrinsic nature of essence of the plant and “oil” is used to indicate a liquid that is insoluble in water.
Essential oils are mainly inhaled aromatically, straight from the bottle or diffused into the air by a diffuser or applied topically to the skin. Some essential oils are used orally, but this is not recommended, unless advised by a licensed practitioner.
HOW THEY WORK IN THE BODY
When essential oils constituents enter our body, they follow a certain route. Whichever mode of application we choose (oral, inhalation, topical), the constituents eventually find their way into our bloodstream. The bloodstream then carries these molecules to the rest of your body where they can interact with cells and other molecules in your body to cause an effect. Then they pass through the liver, where they are chemically changed (metabolized) from oil-soluble into water-soluble substances which are then excreted through the kidneys and urinary tract.
When inhalation is used, the constituents pass both into the lungs and also into the brain. Once in the brain, essential oils constituents may trigger the release of neurochemicals which affect mood, and may be for example invigorating, calming or analgesic.
Main resources & recommended books:Aromatica vol 1. - Peter Holmes LAc, MH
Aromatica vol 2. - Peter Holmes LAc, MH
Aromatherapeutic Blending - Jennifer Peace Rhind
Aromatherapy for the Healing Spirit - Mojay
Essential Oil Safety - Tisserand & Young
The Art of Aromatherapy - Robert B. Tisserand
The Encyclopedia of Essential Oils - Julia Lawless
Tisserand Institute - Essential Oil Education