The largest organ of the human body is the skin. It protects our bodies from the environment, maintains body temperature, excretes waste matter, gives sensory information to the brain and regulates body moisture. We think about our skin more than any other part of our bodies, and we manifest that attention by investing our emotions and about 6 to 20 % of our disposable income into our skin (Lappe, 1996). It is worthy to consider, then, how cosmetic products affect our skin. In this article the psycho-social impact of cosmetics will be examined as well as why cosmetics are deemed necessary. The physiology of skin, how cosmetics affect skin function and the effects of synthetic and natural cosmetic ingredients on the skin will also be considered.
The Psycho-Social Impact of Cosmetics
Our society is preoccupied with the “culture of beauty” (Lappe, 1996) which includes the notion that our skin must always look young and appear free from blemish. Our psychological well-being is often closely enmeshed with perceptions of how our skin appears to ourselves and others. We define our self-image to include the visible representation of our skin to others, so as a result, it has become the “primary canvas on which our cultural and personal identity is drawn” (Lappe, 1996). Cosmetic companies set aside concepts of natural beauty so that flaws such as large pores, fine lines and wrinkles are brought to the fore, influencing our spending habits in pursuit of flawless skin.
In the animal kingdom, most male species are endowed with colourful physical attributes so that a less colourful, but wisely camouflaged female mate will be attracted to it. Humans do not have equivalent ornamentation, so women use cosmetics, specifically make-up, to decorate their faces to attract prospective mates.
The Need for Cosmetics
A cosmetic is any substance which, when applied, results in a temporary, superficial change (Anctzak, 2001). We use a myriad of cosmetics on our skin, from moisturizers to lipstick. Make-up alters our visual appearance by enhancing our facial features through the artistic application of colour. It can beautify the face and be used to express our sense of self to others. Make-up can hide blemishes, scars, under-eye circles or even out our skin tone. It can boost self-esteem, make us feel more attractive and increase our social acceptability in some social situations. Using make-up can contribute to a well-groomed image, which positively influences our confidence, self-esteem, health and morale.
Skin care cosmetics treat the surface layer of the skin by providing better protection against the environment than skin left untreated. Creams treat the skin’s surface by imparting moisture to the skin cells on the outermost layer of the skin. It also forms a thin barrier which traps moisture underneath, thereby preventing the evaporation of water from the skin’s surface. Creams also accelerate the hydration of skin cells on the outer layer, giving the skin a temporarily smooth, plump appearance. Exfoliants improve the appearance of the skin by sloughing away flaky skin, blackheads and some dead skin cells. Astringents improve skin tone and texture by swelling the pore walls so dirt and debris do not collect within. Soaps loosen particles of dirt and grime by dissolving the greasy residue left on the skin from natural skin oils, creams and make-up.
The Physiology of the Skin and How Cosmetics Affect Skin Function
Skin is made up of three main layers: the epidermis, the dermis and the hypodermis. The epidermis is the only layer we can see with our eyes and as we age, remarkable changes occur which are hidden from our view. For instance, the skin gradually thins over time, especially around the eyes. Some cosmeceuticals can minimally re-thicken the skin, but the process of thinning is inevitable. Elastin and collagen, located in the dermis keep the skin resilient and moist, but with ageing these fibres break down to create lines and wrinkles. Exposure to ultraviolet radiation accelerates this process, and since few cosmetics can actually reach the dermis, the idea that a cosmetic can reverse this process is unfounded. The best way to prevent fine lines and wrinkles is to limit our exposure to the sun and ultraviolet radiation.
The skin is a highly complex, dynamic tissue system. One square inch of the skin is composed of 19 million cells, 625 sweat glands, 90 oil glands, 65 hair follicles, 19 000 sensory cells and 4 metres of blood vessels (Lappe, 1996). The outermost layer of the epidermis is called the cornified layer, and is made of sheets of keratin, a protein, and squames, dead, flat skin cells. It is our barrier against dehydration from the environment. It receives its primary supply of moisture from the underlying tissue, since constant contact from the external environment tends to dry out the skin’s surface. When the skin is exposed to dry conditions, the cornified layer can become dry, brittle, firm and if untreated, it can crack and lead to infection. Creams create a waxy barrier to prevent dehydration and keep the skin moist and supple. Underneath the cornified layer lie six more layers of the epidermis responsible for cell generation. The life cycle of skin cells within this layer takes approximately 28 days, so it may take three to four weeks to observe any changes at the skin’s surface from using a new cosmetic.
The skin surface is also home to millions of healthy micro-organisms which increase our immunity to pathogenic, or disease-causing bacteria. Thus, our desire to sterilize the skin also destroys beneficial bacteria, such as streptococcus mutans, and micrococcus luteus . Toners, for instance, are beneficial in keeping bacterial populations down, thus reducing acne flare-ups resulting from microbes which invade and proliferate in the pores. Overuse of anti-microbial agents can produce harmful results when too many beneficial bacteria are destroyed, allowing pathogenic bacteria to multiply unchecked on the skin. The skin also produces antimicrobial proteins, two of which are called defensins and cathelicidins, which increase when the skin is damaged. Perspiration, necessary for the maintenance of internal body temperature, also excretes a germicidal protein called dermicidin to combat bacteria producing body odour. Deodorants also assist in keeping the bacterial population down, thus decreasing the odours produced as they feed on the waste matter excreted by the sweat glands. Research has shown that people who wash excessively are more prone to infection and eczema as a result of ‘washing” away natural bacteria and germicides too frequently Awake 2004.. Eye Primer