Sophia Alvarado
Contributing Writer
At UC Santa Barbara (UCSB), college students spend a lot of time walking, biking, and enjoying the beach. Students are often exposed to the sun and ultraviolet (UV) rays, so it is important to know about the effects of UV light so that we can take necessary precautions, like wearing sunscreen.
Categories of UV Light
UV light stands for ultraviolet light, which are short, high frequency light waves produced by the sun. UV light rays (aka radiation) are organized into three categories: ultraviolet A (UVA), ultraviolet B (UVB), and ultraviolet C (UVC). UVA and UVB are the only two types that can pass through the ozone layer and reach Earth.
What differentiates the two are their different wavelengths (how often the shape of a wave repeats) and the effects that they have on human skin.
UVA rays are the most common; they make up about 95 percent of the UV radiation that reaches the Earth’s surface. They have slightly longer wavelengths that lets them penetrate deeper into the skin. As a result, these rays are primarily associated with tanning and skin aging.
UVB rays have comparatively shorter wavelengths and primarily affect the epidermis, the outermost layer of the skin. UVB rays mainly cause immediate damage like sunburn, which is a major risk factor for developing skin cancer.
UV rays damage the DNA within skin cells. When DNA damage is significant and not repaired correctly it leads to mutations that can cause uncontrolled cell growth and the development of tumors.
UVC rays are the most damaging type of UV radiation with the shortest wavelengths of the UV spectrum. Even though UVC rays have the highest energy, they are almost completely absorbed by the Earth’s ozone layer before it reaches the surface.
Positive and Negative Effects of UV Light
As college students at UCSB, we spend a lot of time on the beach: swimming, surfing, and tanning. Since we spend a lot of time in direct sunlight, there are a few things we should be aware of as we soak up the sun’s rays.
UVB rays are responsible for the production of vitamin D in the skin, which is essential for many bodily functions, including bone health, immune system, muscle health, and mental health. UV radiation can be used in phototherapy, a form of light therapy that uses ultraviolet rays on exposed skin to treat several skin conditions (including psoriasis, eczema, and vitiligo).
UV radiation is also a mood booster because it releases endorphins, the body’s natural painkillers. Endorphins act as neurotransmitters by blocking pain signals and increasing feelings of pleasure and happiness.
Apart from the positive effects, there are many subtle, long-term negative health effects that come from UV ray exposure. This kind of light can damage the DNA in skin cells, which may lead to skin cancer development from genetic mutation and uncontrolled cell replication.
Premature aging is another negative effect of UV rays. Excess UV exposure damages collagen and elastin, essential skin proteins for healthy skin, moisturizing, and preservation of skin. Without them, skin may sag, wrinkle, and lose elasticity through a process known as photoaging. UV radiation can also damage your eyes, resulting in eye conditions such as cataracts, a clouding on the eye lens that clouds vision.
Finding the Ideal Balance
To protect your skin from damage, the U.S. Environmental Protection Agency strongly encourages limiting your sun exposure during the hours of 10 a.m. to 4 p.m., the period of time during the day when the UV index is strongest. The World Health Organization recommends 5-15 minutes of sun exposure, 2-3 times per week, as a healthy amount of UV exposure.
Being outside is important for college students to improve our mental health. Completing homework outside is a perfect way to enjoy UCSB’s weather, but seek shade as a means of protection during the sun’s peak hours. Always use sunscreen with an SPF of 30 or higher before going outside, and remember to reapply throughout the day. It is important to wear sunscreen every day, even during winter, because you can still get sunburned by UVB rays on a cloudy day. Finding the right balance to enjoy the outdoors while protecting our skin is essential to keep ourselves safe.