Oils and butters generally function in body care products as carrier or base oils. Carrier or base oils serve as a foundation for skin care products and for essential oils. Carrier oils are generally extracted from fruits, grains, nuts or seeds, such as olive, wheat germ, peanut or sesame. Many of them are the same products that you use for cooking. The various carriers have particular qualities that make them useful in different situations or for different skin types.
I believe it is very important to choose unrefined cold pressed or expeller pressed oils. These grades of oils have been mechanically pressed rather than extracted with petrochemical solvents such as heptane or hexane. Less heat has been used in the production of cold pressed than expeller pressed oils, which keeps them from becoming rancid and retains more of their nutritional value. Also, unrefined oils are more nourishing than refined oils, whether ingested or used topically. Be aware, however, that unrefined oils are stronger in color and scent than refined oils, and that they may have a cloudy appearance.
Keep in mind too that light, heat and oxygen cause rancidity and spoilage in oils. You may want to purchase oils in relatively small quantities and store them in airtight containers in a cool, dark place such as the refrigerator. Oil-based preparations should be stored in the same way. If an oil or oil-based product begins to smell rancid, it is best to discard it or use it for polishing the floor or furniture.
Almond Oil, pressed from almond kernels, enjoys a lot of popularity in the natural skin care arena. It is a light and nearly odorless oil with a great deal of nutritional value. I find it to be somewhat on the dry side, and often combine it with richer, heavier oils such as peanut or olive. Although cold pressed almond oil is available, the solvent extracted type is much more common. Please read the label to be sure, since the solvents used in the latter are not good for the skin.
Apricot Kernel Oil is made from the inner kernels of the apricot. It possesses properties similar to almond oil, being light, odorless and somewhat drying. Like almond oil it can be used in most skin care preparations, but may also need to be enriched with more emollient oils.
Avocado Oil is a wonderfully rich oil made from the pulp of the avocado fruit. A heavy but penetrating oil that is rich in nutritive and therapeutic components, it is an excellent oil for dry, damaged skin.
Canola Oil is a new hybridized oil from the seeds of the rape plant, a mustard family member used as a forage crop for livestock that was [created by the Canadian government for its low erucic acid content. Ex-peller pressed canola oil is now widely available. It has a neutral and light quality that is good for most skin types and useful in creams and massage oils. Canola oil does not contain many nourishing components, and may be combined with richer oils to increase the nutritive value.
Cocoa Butter, made from the cocoa bean, is solid at room temperature but melts when applied to the skin. It has a delicious chocolate scent that can enhance a product's aroma. It is used as an emulsifier and stiffener in creams. Cocoa butter can also be added to body oils to thicken them. It is highly protective because it stays on the surface of the skin, which helps prevent dehydration. It also has water-repellent properties, which is helpful in swimming situations and with sunscreen products. However, cocoa butter may feel too heavy for some skin types, and a few people are allergic to it.
Coconut Oil is made from the fruit of the coconut palm. It is solid at room temperature, but liquefies when temperatures exceed 76 degrees F. Thus, it tends to loosen and liquefy during the summer months. Coconut oil has a cooling property, which lends itself to sun products and burn remedies. It is used in creams to help emulsify and stiffen them. Coconut oil has long been used by tropical peoples for hair care. I enjoy using it as a hair conditioner, and often include it in the hair products I make.
Flaxseed Oil, pressed from the seeds of the flax (linen) plant, has gained a lot of popularity in the natural health movement due to its high concentration of omega-3 essential fatty acids. Products made from this oil must be kept refrigerated, since its superpolyunsaturated nature is very unstable and goes rancid easily. It also has a strong odor. It may be used alone or added to oils and creams for eczema, psoriasis and other skin conditions.
Grapeseed Oil, made from the seeds of grapes, is the lightest of the oils and virtually odorless. It is also very drying, which should be kept in mind when making products for dry-skin problems. I have not been able to find cold or expeller pressed grapeseed oil, it all seems to be produced with chemical solvents. However, because the oil is so light and odorless, it is favored as the carrier oil by aromatherapists. It serves as an excellent base for perfume blending.
Jojoba Oil is pressed from the seeds of a small desert shrub with leathery leaves. It is technically not an oil, but a liquid wax ester that resembles human sebum, the natural coating that protects our skin and keeps it supple. Jojoba oil can act as a second skin, providing protection and emolliency while still allowing the skin to breathe. It is used extensively in products for dry, aged and damaged skin and hair. I like to use it in sun protection products as well.
Olive Oil is made from the fruit of the olive tree. Virgin-grade olive oil is the first cold pressing of the olive and the most nutritious of olive oils. I find it to be the most stable oil and the least likely to go rancid, so it is a good choice for making herbal-infused oils. Olive oil contains many beneficial substances and can be used alone or in combination in various preparations. Keep in mind that olive oil is a heavy oil with a strong aroma, which should be considered when creating a product. It is absorbed by the skin, but may take a bit longer than other oils. You may choose to combine it with another lighter oil, such as almond, for massage products.
Peanut Oil is rich, heavy and strongly scented. I find that it penetrates the skin well. It is especially appropriate for skin products for dry, malnourished skin. Peanut oil can be used in skin preparations to increase the product's overall nutritive value. It was recommended especially by Edgar Cayce because he thought it resembled human oil and was easily accepted by the skin. However, due to the peanut's susceptibility to fungus, peanut oil can contain undesirable contaminants.
Sesame Oil, made from sesame seeds, is widely available in cold pressed form. It contains natural antioxidants that make it a rather stable oil. It contains natural sunscreen properties, so I like to use it in the sun products I make. It has a very strong odor, and has a warming and drying effect. I often combine sesame oil with more lubricating oils like peanut to create a less drying product. In the Ayurvedic tradition, sesame oil is very popular as a warming substance, and is used for poor circulation and nervous skin problems. While in India I saw many women with long, beautiful black hair coated with sesame oil, which is an excellent conditioner.
Shea Butter comes from the shea tree (Butyrospermum parkii), which grows in West and Central Africa. Its seeds are harvested to make shea butter for food, skin and hair products. Since the French colonized West and Central Africa, it has been used in French cosmetics under the name of karite butter. Shea butter is solid at room temperature and may be used in creams to help emulsify and stiffen them, or in body oils as a thickener. It can make a cream or balm slightly grainy, but this will not alter the effectiveness of a product. Shea butter is extremely therapeutic, helping to heal cracked, aged or damaged skin. It contains some ultraviolet protection, approximately SPF-6, and is therefore useful in sun products. It also contains chemical constituents that help to heal bruising and soreness. It is a very heavy butter that penetrates the skin, leaving it soft and smooth; some people find it too heavy for normal use. Shea butter can be quite expensive and difficult to find, but I have listed some sources of it in the Resources section.
Wheat Germ Oil, pressed from the germ of the wheat berry, is extremely nourishing, and contains significant amounts of vitamin E. It can be added to skin care preparations to increase their therapeutic benefits. However, the odor of cold pressed, unrefined wheat germ oil is very strong and nutty, which should be considered when creating a product. You only need to add a little wheat germ oil to skin care products, as it is extremely concentrated.