Intrigued by how essential oils work but don't understand how or why? Essential oils are highly concentrated, aromatic compounds, and the effects are related to the chemical structure.
Phenols are believed to be antiseptic and antibacterial properties and can be beneficial to the immune system. They "clean" the receptor sites on cells. Pretty powerful stuff! Some of these are "hot" oils however and can irritate the skin. These oils should be heavily diluted. Examples are thymol (thyme), eugenol (clove, cinnamon) and terpinen-1-ol-4 (melaleuca, commonly known as tea tree).
Terpenes are responsible for a multitude of therapeutic effects in oils. There are many different types of terpenes. Monoterpenes reprogram miswritten information in cellular programming, or DNA. Really?! Yes, really. Sesquiterpenes erase or deprogram faulty coding in cellular memory. There is a lot of interesting research on frankincense. Terpenes are also responsible for many of the emotional and psychological impacts that oils can have. Oils high in monoterpenes include pine, orange, balsam fir, ginger and frankincense. Oils high in sesquiterpenes include cedarwood, patchouli, sandalwood and myrrh.
Alcohols are energizing, and have cleansing, antiseptic and antiviral properties. Examples include lavindin* (borneol), rose (citronellol), rosewood (linalool), melaleuca (alpha-terpineol) and lavender (lavendulol).
Aldehydes are antimicrobial and anti-inflammatory. Oils with aldehyde constituents include cassia, cumin, melissa, eucalyptus dives.
Provide decongesting and analgesic benefits and help promote healing. Oils with ketones include camphor, fennel, jasmine, myrrh, peppermint, vetiver.
Esters are soothing, balancing, anti fungal, and help modulate stress and emotions. Oils with esters include birch, wintergreen, bergamot, helichrysum, Roman chamomile, geranium, peppermint.
Oils with high oxide content are known for respiratory decongesting and sinus-clearing benefits. Examples include eucalyptus globules, rosemary, thyme, peppermint, clary sage, clove, German chamomile and rose.
Lactones have antiseptic, anti parasitic and anti-inflammatory properties. Examples include fennel, myrrh, and anise.
*Lavindin vs lavender - Is there a difference? YES! True lavender is Lavendula angustifolia. There is also spike lavender, Lavendula latifolia. Lavindin is a hybrid plant that is a cross between true and spike lavender, with the name lavendula x hybrida. Lavindin has a much higher camphor content. It is a great antiseptic for this reason, and one of the ingredients in the blend Purification. It should NOT be used in place of lavender for this reason, it can be more irritating and particularly should never be used for burns, including sunburns, the way that lavender is. Unfortunately most essential oil labeled "lavender" and products with a lavender scent are actually made from the plant lavindin. Once again - it is worth it to understand where your oils come from.
Info obtained by Essential Oils Pocket Reference by Life Science Publishing as well as Aromatherapy by Valerie Ann Worwood.