Plant and seed oils have been used for centuries and possibly millennia in Nigeria and Africa for the maintenance of healthy skin and the traditional treatment of skin disorders. In recent times, some of these oils have regained popularity due to their availability and affordability coupled with concerns about the side effects of commercially processed skin care products. This is to assess the chemical properties, current knowledge, source of procurement, indications for topical use, benefits, and possible adverse effects of six plant oils and one animal fat commonly used in Nigeria. This is a literature review and interview with traditional healers and alternative health practitioners to document the traditional, medical, cosmetics, and other usage of oils for skin and scalp care in the African context. Literature review was done on the biochemical and pharmacological properties of each of the seven oils. Searches were made from PubMed, African Journal online, Medline, and Google scholar. Medical subject heading terms used in the search include shea butter, coconut oil, palm kernel oil, palm oil, soy oil, Baobab oil, and python oil. Plant and seed oils used locally in Nigeria and other African countries for skin care and treatment have several benefits due to the constituents of the plant oils (free fatty acids, triglycerides, ceramides, phospholipids, vitamins and antioxidants) which have been shown to promote healthy skin barrier function, wound healing and have anti-inflammatory and antimicrobial effects. They are however not without adverse effects, which may be mainly due to processing and storage hygiene. Further studies are required on these oils in view of their potential in the development of novel skincare products and dermatological therapies.

Various plant and seed extracts are utilized for skin care, cosmesis, and alternative skin therapy. One of the most used in Nigeria and many other countries in Sub-Saharan African is shea butter, a thick yellowish butter produced from the nuts of the Shea tree (Vitellaria paradoxa). Shea butter is a well-known multipurpose skin care item in many African countries, and it is believed to have several skin maintenance and healing properties. The taxonomic and physicochemical properties of shea butter are documented in Table 1. 1,2 Shea butter has been shown to have both emollient and occlusive properties which enables it to trap moisture in the epidermal layers of the skin. 3,4 Shea butter was found superior to mineral oil in preventing trans-epidermal water Loss (TEWL). 5 Shea butter was recommended for repairing dry inflamed skin caused by dermatitis and as a nighttime T A B L E 1 Shea butter: taxonomic and physicochemical properties Taxonomy of the African Shea Tree Family; Genus Sapotaceae; Vitellaria. Species Vitellaria paradoxa. Subspecies V. paradoxa paradoxa and V. paradoxa nilotica. Former name/ Synonym Butyrospermum parkii; B. paradoxum. Regions found Semi and sub-humid savannas of subsaharan Africa. Main producing countries Ghana, Senegal, Nigeria.

Introduction: Skin cancers are uncommon in Africans and dark-skinned people but when diagnosed they often have a poor prognosis. Darker skin has increased photoprotection against the high-intensity ultraviolet radiation (UVR) of the tropics and the subtropics due to high eumelanin content. While UVR has been found to play a significant role in the pathogenesis of cutaneous malignancies in Caucasians, it is of less significance in Africans.