Vegetable, nut and seed oils are called “carriers” because they are used to “carry” or to transport a substance such as an essential oil to another place. In this case the essential oil is added to the carrier oil for the purpose of applying the essential oil directly to the skin. The oils used most frequently are Sweet Almond, Sunflower and Olive.
Lotions, which are water-based can also be used as carriers and are often preferred as they are not so oily. Although oil and water do not mix, spritzers can be made, using essential oils with distilled waters for another way to carry the oil. Other types of carriers include alcohol, vinegar, or herbal oils.
Many vegetable, nut and seed oils can be found on the shelf of your local grocery. These are usually highly refined, and may contain petroleum residues and preservatives. A carrier oil is a fatty oil which is often used to extend or to dilute the essential oil to make it go further. Most of the molecules of these carrier oils are very large, and thus cannot be diffused, and are generally too large to penetrate the skin, but they do slide smoothly over the skin and can hold moisture and protect the skin. The carrier oil will slow down the rate of absorption of the essential oil. Some carrier oils contain therapeutic properties in the form of smaller molecules.
Essential Oils, on the other hand, have smaller molecules and are generally obtained through the distillation process, so they are highly concentrated. Since it takes so much of the original product such as flowers, bark, leaves, resin or plant product to produce the small amount of essential oil, these precious drops are very valuable and expensive. They do not have the oily feel to the touch like carrier oils do. Essential oils have wonderful and varied aromas while carrier oils usually have no particular aroma until they are heated. Essential Oils, if properly cared for can last for years, while carrier oils tend to go rancid relatively quickly. For this reason, it is recommended that carrier oils be refrigerated for storage to help extend their shelf life.
For skin care, carrier oils that are unprocessed, organic, and cold-pressed are the most valued by aromatherapists and massage therapists.
Examples of popular carrier oils are:
1. Sweet Almond Oil (Prunus dulcis) is a favorite of massage therapists, Sweet Almond oil is one of the most frequently used carrier oils, and is particularly effective in relieving itching in dry skin. It is considered safe for cosmetic use, is high in vitamin E and has a relatively long shelf life. It is more expensive and harder to find since it is not a cooking oil.
2. Avocado oil (Persea Americana) is made from the large seeds of the plant; this oil is also good for dry skin. It contains vitamins A, D and E and is noted to restore and maintain skin tone and elasticity and to help prevent wrinkles.
3. Coconut oil (Cocos nucifea) is expressed under high pressure and filtered from the coconut kernel. It is actually solid at room temperature but melts easily at body temperature. It is relatively expensive and may cause skin irritation in people who have nut allergies.
4. Grapeseed oil (Vitus vinifera) is expressed from the seed of the grape which are often a byproduct of wine making. It is very lubricating and contains antioxidants. It is mildly astringent and is often used in massage, but has a very short shelf life.
5. Kukui nut oil (Aleurites moluccana), from the state tree of Hawaii, is very light and so non-greasy that it is suitable even for oily skin. It is high in vitamins A and E, and has been used for centuries to aid skin that has been damaged by the sun or salt water.
6. Olive oil (Olea europea) is rich in chlorophyll, which is very healing. Its shelf life is twice as long as most other carrier oils. The extra virgin oil has a strong smell, so a lighter version is usually used in aromatherapy.
7. Rosehip Seed oil (Rosa mosqueta or Rosa rubiginosa) is high in vitamin C and is very rejuvenating and healing. It is useful in scar tissue repair and in treating damaged tissue cells. It is noted to be good for aging spots. It is relatively expensive.
8. Sesame seed oil (Sesamum indicum) is made from pressing the seeds. It is soothing lightweight oil rich in Vitamin E, minerals, and lecithin. It can speed healing, prevent drying, and has a sunscreen effect. It is often used in Ayurvedic medicine for skin preservation. It has a short shelf life
9. Sunflower seed oil (Helianthus annuus) is rich in vitamins A and E and in lecithin. This light oil leaves what some call a second skin after drying so it is particularly useful in the winter. This oil is often found in body lotions
Other carrier oils include Apricot-kernel oil, Arnica infusion oil, Borage oil, Calendula infusion, Canola oil, Castor oil, Cocoa butter oil, corn oil, Evening Primrose oil, Hazelnut oil, mineral oil (a synthetic by-product of petroleum which is not recommended), Mullein infusion, Peanut oil, Peach kernel oil, Pecan nut oil, Rosehip seed oil, Safflower oil, St. John’s Wort infusion, Soy oil, Squalene (shark oil), Vitamin E oil (from various vegetables), Walnut oil and Wheat germ oil. There are others. These are more commonly used.
Three substances used as carrier oils which are actually waxes are: lanolin which is obtained from the wool of sheep, Shea butter, a wax from the Shea nut tree in South Africa, and Jojoba which is pressed from the beans of a desert shrub. Jojoba (Simmodsia chinensis) is very similar to the protective sebum produced in the human skin and is probably the best moisturizer of all. Additionally it has a very long shelf life. Thus it is a very popular carrier for aromatherapy.