Why Do We Need Sunscreen?

Image by Flickr.com, courtesy of Robby!

Everyone needs sunscreen to protect their skin from damaging UV rays from the sun and sunburn. Using sunscreen products decreases the chances for sunburn and can prevent skin cancer or malignant melanoma. According to the American Cancer Society, in 2009, more than 1 million people were expected to be diagnosed with skin cancer and research studies link skin cancer with sun exposure on unprotected skin. The sun’s drying rays also prematurely age the skin and lead to wrinkles.


Your skin responds to excessive sun exposure by turning red, becoming hot, and slightly painful to the touch. Severe sunburns cause skin blistering and peeling. The sun’s rays have two types of harmful UV rays--UVA and UVB. UVA rays penetrate your skin more deeply than UVB and are the cause of premature skin aging. UVB rays are the primary sunburning agent.


You need to use a sunscreen because it protects your skin from UV damage and sunburn. Sunscreens are over-the-counter products that come in lotions, gels, ointments and sprays. The strength of the sunscreen protection is measured as SPF--or sun protection factor--which typically ranges from 15 to 45. The higher the SPF value, the greater the protection. However, this is not a true linear relationship--a SPF of 30 is not twice as effective as an SPF of 15.

When to Use Sunscreen

Everyone needs sunscreen when outdoors for more than 15 minutes between 10 a.m. and 3 p.m. or if they're in direct sunlight coming through a window (UVA rays pass through glass). You should wear UV protection on cloudy days, too.

How to Use

Apply sunscreen 15 to 30 minutes before going outdoors. Cover all areas of the skin that will be exposed to the sun’s rays. Apply liberally. Most people, including children, need about 1 oz. of product to cover exposed areas sufficiently. Reapply every two hours. If you are swimming, reapply more frequently.


Children are at particular risk because they forget to reapply as often as needed when they are busy playing. Beach and lake vacations present special challenges for parents to monitor sunscreen coverage on children because water enhances the effect of radiation. According to a recent study discussed in Science Daily, 7-year-old children who vacationed at the beach had a 5 percent increase in skin moles--a major risk factor in malignant melanoma.