Shea butter has been used for centuries by African men and women to promote healthy skin and hair. Over the past couple of decades, manufacturers of skin- and hair-care products in the United States have caught on to the many benefits it provides. This butter is sold full-strength with no additional ingredients. You'll also find it listed as an added ingredient in many skin moisturizers and hair conditioners.
Shea butter is harvested from the fruit of the karite tree. This tree may be found throughout the savannas of Africa, and it bears fruit that contains hard, white kernels. Under traditional methods of extraction, the kernel is cracked, heated and boiled in water until the butter floats to the surface. It is then placed in gourds, where it remains until it has cooled and set.
A more modern method of extraction employs an expeller press. Used to pulverize the kernels, this press typically produces more butter than traditional extraction; it also tends to be much faster.
The benefits and applications of shea butter are legion. It's a potent emollient that may be used to soften and moisturize dry, chapped skin, but that's only the tip of the iceberg. A clinical study performed by F. Renard as part of his doctoral thesis suggests that shea butter may also be an active ingredient with anti-aging properties. The study determines that this butter battles skin thinning and fosters the development of collagen. More than half of the volunteers studied by Renard also showed a visible decrease in wrinkles caused by sun damage.
In their report "Shea Butter: The Revival of an African Wonder," researchers M. Pobeda and L. Sousselier cite studies that prove shea butter is effective in the treatment of hand dermatitis and sunburn; it also appears to effectively diminish the appearance of scars.
In Africa, shea butter also is used as a nasal decongestant; Pobeda and Sousselier point to research that confirms its effectiveness in this area. Another study cited by these researchers states that shea butter can be used to ensure that active ingredients are effectively released onto the skin. This is one reason why so many manufacturers choose to use it in skin- and hair-care products.
Refined shea butter is that which has been refined and processed using high heat and chemicals. The American Shea Butter Institute states that while this type of shea butter may have some moisturizing properties, it loses much of its healing and therapeutic properties in the refining process. Refined shea butter typically is odorless, with a pure white color. In some cases, hexane---a neuropathic toxin---is used in the refining process.
According to the American Shea Butter Institute, unrefined shea butter is the better choice if you hope to reap the full spectrum of benefits it offers. Unrefined or raw shea butter is extracted without the use of toxic chemicals or synthetics. It typically has a nutty aroma, and its color ranges from cream to grayish-yellow. Note, however, that while its fragrance is relatively mild, some people find the smell of unrefined shea butter off-putting.