Clear, glowing skin is one of today’s most important hallmarks of beauty. No matter how advanced the latest skin care technology may be, you still have to learn how to care for your client’s skin and know what you should do to keep it healthy. That means you must study the structure of the skin, how skin grows, and why it is important to maintain a healthy diet.
Blood supplies nutrients and oxygen to the skin. Nutrients are molecules from food, such as protein, carbohydrates, and fats. These nutrients are necessary for cell life, repair, and growth. The skin cannot be nourished properly from the outside in with cosmetic products; it must have nourishment from foods that we eat. Lymph, the clear fluids of the body that bathe the skin cells, remove toxins and cellular waste, and have immune functions that help protect the skin and body against disease. Networks of arteries and lymph vessels in the subcutaneous tissue send their smaller branches to hair papillae, hair follicles, and skin glands.
The skin contains the surface endings of the following nerve fibers:
Motor nerve fibers are distributed to the arrector pili muscles attached to the hair follicles. Motor nerves carry impulses from the brain to the muscles.
Sensory nerve fibers react to heat, cold, touch, pressure, and pain. These sensory receptors send messages to the brain.
Secretory nerve fibers are distributed to the sudoriferous (sweat) and sebaceous (oil) glands of the skin. Secretory nerves, which are part of the autonomic nervous system, regulate the excretion of perspiration from the sudoriferous glands and control the flow of sebum (a fatty or oily secretion of the sebaceous glands) to the surface of the skin.
Acne and Problem Skin Common skin problems that affect clients’ appearance, such as acne, can become a source of great concern. Most people have acne or another skin issue at some time in their lives. Acne is both a skin disorder and an esthetic problem, and it is a major concern to anyone who suffers from it. Frequently misunderstood to be a teenage skin disorder, it can affect people at almost any age. Women often do not have acne problems until they reach their 20s or 30s or beyond. Because it affects the appearance, it is of interest to cosmetologists and estheticians, who are in a position to help their clients with treatment for minor cases or to provide dermatological referral for more severe acne.
Acne is a disorder affected by two major factors: heredity and hormones. People with acne inherit the tendency to retain cells that gather on the walls of the follicle, eventually clumping and obstructing the follicle. Retention hyperkeratosis (hy-pur-kair-uh-TOH-sis) is the hereditary tendency for acne-prone skin to retain dead cells in the follicle, forming an obstruction that clogs follicles and exacerbates inflammatory acne lesions such as papules and pustules.
The oiliness of the skin is also hereditary. Overproduction of sebum by the sebaceous gland contributes to the development of acne by coating the dead cell buildup in the follicle with sebum, which hardens due to oxidation. This conglomeration of dead cells and solidified sebum obstruct the follicle.
Propionibacterium acnes are anaerobic (ann-air-ROH-bic), which means that these bacteria cannot survive in the presence of oxygen. When the follicles are obstructed, oxygen is blocked from the bottom of the follicles, allowing acne bacteria to multiply.
The main food source for acne bacteria is fatty acids, which are easily obtained from the abundance of sebum in the follicle. These bacteria flourish in this ideal environment, which is void of oxygen and with plenty of food (sebum) for the bacteria. The bacteria multiply, causing inflammation and swelling in the follicle, and eventually rupture the follicle wall. When the wall of the follicle ruptures, the immune system is alerted, causing blood to rush to the ruptured follicle, carrying white blood cells to fight the bacteria. Blood will surround and engulf the follicle, which is what causes the redness in pimples.
An acne papule is an inflammatory acne lesion resulting from this wall rupture and infusion of blood. A pustule forms from the papule when enough white blood cells accumulate to form pus, which is primarily composed of dead white blood cells.