Tanned skin in the middle of summer is charming, but most people still prefer clear and clean skin. The whitening functional cosmetics demand increases more as summer passes and fall approaches. There is a lot more demand for whitening cosmetics in middle-aged women. As skin aging progresses, their skin color becomes dull, and pigmentation becomes more likely. Whitening cosmetics: are they effective on my tanned skin?
Functional cosmetics help whiten the skin, improve wrinkles, tan the skin beautifully, or protect the skin from UV rays. It is divided by their functions into whitening, wrinkle improvement, and UV ray protection. In the 18th century, the development of industry, chemistry, and pharmacy led to the beginning of functional cosmetics, and they became popular through chemical processes in the 19th century.
Whitening cosmetics are made into lotions, liquids, creams, facial mask packs, etc., using ingredients registered as whitening by the Food and Drug Administration. There is a total of eight ingredients registered, including paper mulberry extract, arbutin, ethyl ascorbyl ether, oil-soluble licorice extract, ascorbyl glucoside, niacinamide, alpha-bisabolol, and ascorbyl tetraisopalmitate. Those eight ingredients have proven efficacy and stability through evaluation and clinical trials. Whitening cosmetics should include a certain amount of ingredients for effectiveness using these ingredients.
Whitening cosmetics 'inhibit melanin production.' People may think that whitening cosmetics make skin white, but they do not whiten the skin by breaking down melanin that has already occurred. Sunscreen blocks UV rays that produce melanin, and whitening cosmetics prevents melanin from being produced within the skin after exposal of UV rays.
'Melanocytes,' cells that produce melanin, are located in the basal layer at the bottom of the epidermis. The skin is divided into the epidermis, 50 to 100㎛ thick, and the dermis, 2 to 3mm thick just below. The epidermis comprises the stratum corneum, granular, spinous, and basal layers that order from the surface. When UV rays stimulate the skin, the tyrosinase enzyme oxidizes tyrosine, a protein within melanocytes. Oxidized tyrosine creates melanin, and skin pigmentation occurs when it rises to the stratum corneum.
It takes about thirty days for melanin to be produced in the basal layer and rise to the stratum corneum. The newly created skin cells push up old skin cells, the old skin cells become dead skin cells and fall off, and new skin cells in the granular layer immediately below rise the form a new stratum corneum. The reason why tanned skin in the summer gradually becomes whiter over the fall and winter is not because melanin is broken down but because skin cells containing melanin become dead skin cells and fall off.
Paper mulberry extract, arbutin, alpha-bisabolol, and oil-soluble licorice extract prevent the activation of the tyrosinase enzyme that promotes melanin production. Ascorbyl glucoside, ethyl ascorbyl ether, and ascorbyl tetraisopalmitate prevent tyrosine stimulated by the tyrosinase enzyme from oxidizing. Niacinamide inhibits the transition of melanin from melanocytes to keratinocytes. It blocks the final step in which melanin enters skin cells. In addition, hydroquinone, a medicine, forms an ointment that destroys skin cells containing melanin and helps new cells grow. Over 4% containing ointment requires a prescription, and 2% can be purchased without a prescription.
Dr. Yoo Deuk Lee of Gangnam Leejiham Skin Clinic emphasized, "The melanocytes that produce pigment are not in the dermis but in the basal layer, the bottom layer of the epidermis. The whitening ingredient is only effective when absorbed; if applying whitening cosmetics consistently, the effect may appear little by little after about a month. However, it is also important to keep applying sunscreen to block UV rays."
Meanwhile, "If you make your tanned skin after a vacation in a short time, I recommend vitamin C ionized therapy. Vitamin C also reduces the activity of melanocytes, but it is effective because ionized vitamin C passes through the melanocyte membrane, enters the cells, and is absorbed. If you plan to get laser toning, get a mild treatment. If the laser is too strong, it will be as irritating as UV rays, so it should be applied gently to avoid activating the epidermal pigment." He added.