Sebaceous Glands

Sebaceous glands secrete an oily substance called sebum (Latin, meaning fat or tallow) that is made of fat (lipids) and the debris of dead fat-producing cells. In the glands, sebum is produced within specialized cells and is released as these cells burst; sebaceous glands are thus classified as holocrine glands. Sebum itself is odorless, but its bacterial breakdown can produce odors. Sebum is one cause of some people experiencing "oily" hair or skin if not washed for several days. Earwax is partly composed of sebum. Sebum acts to protect and waterproof hair and skin, and keep them from becoming dry, brittle, and cracked. It can also inhibit the growth of microorganisms on skin. Sebaceous glands are a branched type of acinar gland, these glands exist in humans throughout the skin except in the palms of the hands and soles of the feet. Sebaceous glands can usually be found in hair-covered areas, where they are connected to hair follicles. The glands deposit sebum on the hairs, and bring it to the skin surface along the hair shaft. The structure consisting of hair, hair follicle, arrector pili muscle, and sebaceous gland is known as a pilosebaceous unit. Sebaceous glands are also found in non-haired areas (glabrous skin) of eyelids, penis, labia minora, and nipples. Here, the sebum traverses ducts which terminate in sweat pores on the surface of the skin. Pores range in size from 50 to 80 μm on average. The inner surface of the lip and the buccal surface of the cheek can potentially contain ectopic sebaceous glands commonly known as Fordyce's spots or Fordyce granules. These occur as yellowish circular dots that form clusters. 80 percent of the population have Fordyce granules and these sebaceous glands are asymptomatic. At the rim of the eyelids, meibomian glands are a specialized form of sebaceous gland. They secrete sebum into the tears coating the eye, to slow evaporation.

Natural oils

Natural oils contain hundreds of organic constituents such as hormones, vitamins and other natural elements that can be beneficial for the skin. Natural oils can be divided into two general categories - essential oils and carrier or base oils. Essential oils are volatile compounds found in plans. They give fruits, flowers, herbs and spices their fragrance and flavor. Obtained by distillation or expression, essential oils are highly concentrated and used at a very low concentration. Carrier oils, such as almond, sunflower, olive, walnut and other oils are use