Skin types is not a straight forward topic. In this article, we will consider the extremes of dry skin and oily skin as well as sensitive skin.
The skin is a homeostatic organ that helps to control the heat, fluid balance, and immune status of the body. As the cover of the body, exposed to the environment and rubbing against the environment, it is itself an adaptive organ. In particular, the skin of the face and the neck, so frequently exposed to sunlight, heat or cold, and wind, becomes adapted for such exposure.
Black people would sometimes be surprised by the difference in colour between the skin of the abdomen and upper thighs compared to the much darker tone of the face, neck, and arms. The skin adjusts the quantity of melanin in the epidermis according to its sensitivity to the elements, especially sunlight and heat. Another adaptive process is the thickening of the skin in response to frequent touch, abrasion, or assault. The soles of the feet, the palms of the hands, the elbows, the knees, and the buttocks are parts of the body where adaptive changes reinforce the skin’s protective properties. The longer or greater the contact with the environment, the thicker the skin becomes. Muslims and other people who pray by touching their foreheads on the ground develop a thick spot on the fore head. Many monks develop thick skin on their knees for praying kneeling.
One can observe oneself sweating instantly and profusely on entering a very hot room. The skin is in this case performing a homeostatic role – to maintain the body temperature and prevent it from rising because body enzymes and functions need normal temperature to work well.
The skin demonstrates various other adaptive and homeostatic processes which may be structural or functional, molecular or overt.
Thus for any person, there may be differences between the appearance of the skin in various parts of the body, some parts looking soft and smooth and some parts looking dry and callous.
The oil glands (sebaceous glands) in the skin produce a protective fatty substance, sebum. People with dry skin do not produce enough sebum and people with oily skin produce excess sebum. The sweat glands too can produce little or no sweat or excess sweat. Some people have sensitive skin which is easily challenged by environmental factors. They may keep developing, itch, rash, or redness. We tend to use the skin of the face to determine our skin type as oily, dry, or sensitive.
We should care for our skin according to the skin type and skin area of the body. For young people, the concern may be to avoid build-up of callous. For mid-lifers, the concern may be to reduce the lines and wrinkles and to slow aging. We should know that our genetic makeup, age, geographical environment, as well as what we eat and how much we drink all affect the look of our skin. Whatever the skin type, it is important to exfoliate and moisturize regularly.
Bathing with soap alone is not enough. Soap should be applied with a bath sponge to exfoliate dead skin. Natural bath sponges are commercially produced from harvested Spongia officinalis, an animal that lives in the Mediterranean Sea. Synthetic mesh bath poufs for better scrub or wash cloths for milder scrub may be used in place of the sponge, depending on how sensitive one’s skin is. In West Africa raffia sponge derived from palm trees has been used from time immemorial. Newer commercial versions prevent clogging of drainages with sponge fibres. The loofah (luffa) is another good scrubber derived from a cucumber-like plant. The fruit is left to dry leaving the fibrous skeleton that is used as a bathing sponge. Some of these materials are attached to a handle or stick for effective scrubbing of the back or hard to reach areas. These materials used to bath help to exfoliate and also dislodge bacteria and dirt in the pores of the skin. How often we use a sponge or exfoliator depends on our exposure to environmental factors and sensitivity of our skin. Many Africans routinely (daily) use a scrub while Caucasians may occasionally use a scrub and routinely use a wash cloth. The sponge or scrubbing material should be properly rinsed out after use because retained minute debris can promote microbial growth of bacteria, fungi, or viruses. In fact, synthetic bath poufs, because they are durable, should be rinsed with mild disinfectant frequently to keep them sterile. To be continued
Dr. Theresa Adebola John is a lecturer at Lagos State University College of Medicine (LASUCOM) and an affiliated researcher at the College of Medicine, University of Tennessee, Memphis. For any comments or questions on this column, please E-mail: firstname.lastname@example.org or email@example.com