When you want to protect your skin against the sun’s ultraviolet rays, which can cause cancer, there are lotions that you can apply with varying degrees of protection. There are also products that enable you to achieve an instant tan and some that can even make your skin lighter. The current ideal of beauty is to have a light to moderate tan. Tans are viewed as fashionable, healthy, and attractive. However, those who tan do not only put their health at risk from skin cancer but also do long-term damage to their skin, which eventually takes on the texture of leather.
Ultraviolet rays can penetrate deeply and can trigger cancer by damaging DNA and the immune system. Most human eyes do not register wavelengths shorter than 400 nm, but if they could then we would see two more colors: ultraviolet-A, which has wavelengths 400-320 nm, and ultraviolet-B, 320-280 nm. Although we cannot see UV-A and UV-B, our eyes can be damaged by them and our skin reacts to them: UV-A causes it slowly to go brown; UV-B produces a quicker response and it goes a fiery red. UV-A rays are sometimes referred to as the aging rays because that’s the effect they ultimately have, while UV-B rays are called the burning rays because they cause blood vessels near the skin’s surface to dilate and carry more blood, thereby making the skin feel hot and look red.
The most effective UV-blocker is a chemical pigment called melanin, which is produced in the upper layers of the skin in cells called melanocytes. The more UV-A is absorbed, the more melanin is formed, and the deeper the color of the skin becomes. In fair-skinned individuals, the skin takes time to produce melanin, and so it cannot protect against sunburn following sudden exposure. Skin cancer is the downside of prolonged sunbathing, but not all exposure to the sun is bad, and time spent outdoors is generally beneficial. The action of UV rays on the skin makes a valuable contribution to the body’s need for vitamin D which helps maintain the skeleton, prevents clinical depression, and also protects against heart disease. Mild sun exposure daily can prevent other forms of cancer such as colon, breast, and prostate cancers by boosting the amount of vitamin D in the body. Although we can get vitamin D in our diet, that produced by sunlight falling on the skin appears to stay in the body longer.
Sunblock is an opaque substance that physically blocks ultraviolet rays from reaching the skin. Zinc oxide and titanium dioxide are known as sunblock. A sunscreen is transparent and absorbs the ultraviolet rays. Every year in the United States, more than half a million people develop some form of skin cancer, and the American Cancer Society claims that one in six people will experience this disease in their lifetime. The most common type is basal cell cancer, which forms as raised, hard, red spots on the most exposed parts of the body: the face, hands, and neck. The next most common type is squamous cell cancer, which is a hard-surfaced lump that generally appears on the lips, ears, and hands. Neither a basal cell nor a squamous cell cancer is life-threatening because they do not spread to other organs and are easily removed. The same cannot be said of the third form of skin cancer, melanoma, which does spread. It often starts as a mole, which then grows in an unusual way and turns a blue-black color. Thankfully, melanoma is very rare; however, it kills about 6 thousand Americans every year.
There are three ways we can protect our skin against UV rays: reflect the rays away from the body; absorb the rays but deactivate them, or prevent and repair the damage they cause. Fortunately, there are chemicals available to do all three. A good sunscreen should include microfine titanium dioxide or zinc oxide to protect against UV-A, and an organic compound to protect against UV-B. It should be easy to apply to the skin, giving a continuous film, and yet be invisible. It should not be sticky or easily washed off when swimming, although it should be easily removed using soap or body wash. Most importantly, it should have a reasonably high sun-protection factor (SPF) of at least 30. SPF is a measure of the degree to which a sunscreen reduces the UV rays reaching the skin’s surface. An SPF of 30 will give you 4 percent extra protection than an SPF 15. It screens out 97 percent of the sun’s UV rays, compared to 93 percent for SPF 15.
The best way to protect your skin against UV rays is to avoid going out in the sun between the hours of 11 a.m. and 3 p.m. Outside these hours, use sunscreen with an SPF factor of 30 and if possible, clothing to cover exposed skin.
One of the signs of aging is the appearance of small patches of melanin known as liver spots. To stop these from forming, the metabolism that produces them must be blocked, and that means inhibiting the tyrosinase enzymes that convert tyrosine to melanin. Tyrosinase is the enzyme that causes a cut apple to quickly turn brown. Tyrosinase can be deactivated so that it loses its oxidative function. If you cut an apple and then dampen it with lemon juice, it remains white. This is because the vitamin C in the lemon juice deactivates the enzyme. Natural skin lightening chemicals besides Vitamin C that inhibit tyrosinase are: kojic acid, licorice extract, scutellaria extract, and mulberry. These ingredients need to be present in a substance that can penetrate the skin and need to be used for several weeks before results are seen.
– Nikki Catania, LE