Ultraviolet (UV) Radiation is a form of electromagnetic radiation that comes from the sun and man-made sources like tanning beds. Our current concerns with UV radiation are the rays that come from the sun. Over the past couple decades, humans have been using products which result in ozone layer depletion. This decreases our atmosphere’s natural protection from the sun’s harmful ultraviolet (UV) radiation. Several major health problems, such as skin cancer(melanoma and nonmelanoma), premature aging, cataracts and other eye damage, and immune system suppression, all result from overexposure to these harmful rays.
UV radiation is divided into 3 main types:
- UVA rays- These rays have the least energy among UV rays and constitute around 95% of all UV radiation that reaches the earth’s surface. They have longer wavelength (320-400nm) and cause skin cells to age and can cause some indirect damage to cells’ DNA. They are mainly linked to long-term skin damage such as wrinkles but may also play a role in some skin cancers
- UVB rays- These rays have slightly more energy than UVA rays as they have shorter wavelengths (290-320nm). They can damage the DNA in skin cells directly, and are the main rays that cause sunburns
- UVC rays- These have more energy than the other types of UV rays with the shortest wavelengths (200-290nm). Fortunately, because of this, they react with ozone at the atmosphere and don’t usually reach the ground, so they are not normally a risk factor for any diseases.
Although there are several negative effects of UV rays on the body, there is one positive impact. Human skin makes Vitamin D when it is exposed to UV rays from the sun. This vitamin not only assists in growth and maintenance of the bone, but it also aids in regulation of electrolyte metabolism, protein synthesis, gene expression, and immune function which is why it is largely important to athletes, ranging from hikers, to tennis players and runners. However, the level at which the rays influence vitamin D synthesis is largely unknown as it is dependent on other factors such as age, darkness of skin, and intensity of sunlight and can vary across several groups of people.
(Running in the sun)
UV rays can positively impact athletes, but only on a small scale. Recent studies show that athletes, ranging from hikers, to tennis players and runners exceed the recommended ultraviolet exposure limit by up to eight-fold during the summer and autumn months, putting them at a high risk for UV ray related conditions. While regular physical activity is associated with a reduced risk of most cancers, skin cancer is an exception. For malignant skin cancer, those in the 90th percentile for physical activity have an increased risk of cancer than those in the 10th percentile. Sun protection in these groups is especially important as multiple studies demonstrate an elevated risk of skin cancer for those who regularly participate in outdoor sports or exercise.
Reducing the risk of skin-related conditions
It’s not possible to avoid sunlight completely, but there are ways to help ensure that people don’t get too exposure to UV rays:
- When outside, try to come to shade frequently to prevent long interrupted hours in the sun
- Protect skin with clothing that covers arms and legs
- Wear a hat to protect head
- Use sunscreen
In doing so, people can enjoy the sun and ensure that they don’t develop any life threatening conditions.