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Acne Vulgaris is the most common dermatological condition in the United States and affects a wide variety of people. While not a serious disease, acne can cause scarring and psychosocial distress. This article discusses the physiology of acne, the functional medicine perspective on acne, and conventional and complementary and alternative therapies to treat acne.
Physiology of Acne
Skin is the largest human organ that protects the body from infection; it serves as a waterproof barrier to the outside, protects the body from the sun, insulates the body, repairs itself, and produces vitamin D. With so many functions, it has a complex structure. Human skin is made up for three layers: 1) the epidermis (the outside layer), 2) the dermis (located directly beneath the epidermis), and 3) the subcutaneous layer (the bottom fatty layer under the dermis). The skin also has hair follicles, sensory nerves, blood vessels, lymph vessels, and sweat glands.
Acne begins with a hair follicle that gets blocked. Each hair follicle is comprised of a sebaceous gland that produces an oily substance called sebum. Sebum consists of different lipids and serves to keep the skin lubricated and waterproof. It also serves to transport dead skin cells, called karatinocytes, from inside the hair follicle away from the body, where they flake off.
People with acne have excessive sebum production. When the hair follicle that comes out of a person’s pore gets blocked with excessive sebum, then dead cells cannot exit the hair follicle. The keratinocytes and excess sebum clump together and create a clog in the sebaceous ducts and hair canal. This clog or plug is called a microcomedo; as the plug grows larger with trapped sebum, the microcomedo becomes a visible comedo. There are two types of comedones: 1) blackheads occur when the comedo enlarges and pops through the skin. The black color is due not to dirt but to a build-up of melanin. 2) Whiteheads happened when the comedo stays below the surface of the skin; the white bubble seen is the trapped sebum and dead cells. Comedos form over the course of two to three weeks.
Sometimes the microcomedo gets infected by a bacterium called propionibacterium acnes (p. acnes) or staphylococcus epidermidis (s. epidermidis) and creates an inflammatory lesion. There are three types of lesions: 1) a papule is a small red bump that is commonly called a pimple or a zit and does not appear to have pus, which are white blood cells 2) a pustule is a papule with pus, and 3) a nodule is a large, tender, inflamed, and often painful pus-filled pustule that is deep in the skin. (Goodheart, 2006, p. 17-33). These three types of lesions are called inflammatory lesions and can be located under any of the three layers of skin.
The endocrine system plays a large role in the formation of acne. Androgens, otherwise known as “male hormones,” can help regulate how much sebum the sebaceous glands produce. While people with acne may not be producing any more androgens than non-acne ridden people, their glands may be very sensitive to the androgens and react by producing more sebum. Adolescence is often the worst time for acne since androgen production is increasing.
Women also produce androgens at a lesser rate than men, and also produce estrogen and progesterone. Doctors differ in their opinion of the role of estrogen in the production of acne. Some think that as the levels of progesterone decrease as women get older and estrogen increases, the acne gets worse. Other doctors think that estrogen is helpful, as it can bind with testosterone and other androgens and reduce their production (Perricone, 2003, p.28).