Carrier or base oils are slippery, fatty oils that pure essential oils can be added to for external application and if you are using a EO supplement, some can be used to dilute oils for internal use.
The minute the cap is opened on a bottle of essential oils, the fragrant molecules begin to escape. Some oils evaporate faster than others. Frankincense is ironically one of the most expensive, precious of EOs and also the most quickly evaporating of all! Heavier, resinous EOs like myrrh and vetiver will become sticky and very thick when exposed to air over a period of time.
Carrier oils help "trap" the lighter EO molecules and enable them to dispersed in a massage or other topical application without rapidly disappearing into thin air. They also provide a slippery texture for rubbing on the skin as pure EOs are not greasy by nature.
Carrier oils help dilute stronger essential oils such as clove, thyme, and oregano to avoid skin irritation. There are many different carriers that can be used with essential oils. Some of the most popular are:
Grapeseed Oil --very lightweight. Can be found in most grocery stores. Good for topical and internal application. Goes rancid fairly quickly if not refrigerated.
Olive Oil --light to heavyweight. Usually has a distinctive scent. Excellent for internal applications. Can go rancid eventually.
Jojoba Oil -medium to heavyweight. Actually a plant wax, not oil. The closest to human sebum. Very safe for babies and children, gentle, hypoallergenic. Does not go rancid. Best for topical application. More expensive, but does not make massage sheets smelly.
Almond Oil -light to mediumweight. I avoid this oil in my massage practice since more and more individuals have allergies to nuts.
Pure Aloe Vera Jelly --excellent for applying EOs to burns and damaged tissue.
Basic Dilution Ratios:
This is for application to specific areas such as peppermint on the abdomen for indigestion or eucalyptus on the chest for congestion. A stronger dilution would be needed for infections.
Children and Elderly: 10 drops of EO in 1 Tbsp of Carrier or Base. One or two drops of this mixture can be applied to specific areas.
Adults: 20 drops of EO in 1 Tbsp of Carrier or Base. Two to five drops of this mixture can be applied to specific areas.
Full Body Massage Oil: 2-3 drops of EO in One or Two ounces of Carrier or Base. This also can be mixed with Epsom or Sea Salts for the bath. Be careful as any greasy oils in the tub or shower may make surfaces slippery!
Never drop essential oils or carrier oils directly into the ears or eyes. If undiluted EOs get into eyes use a carrier oil to wipe it toward the outside corners of the eye, do not flush with water.