The Sun and Your Skin

Sunlight is essential to good health, but it can also be extremely dangerous. Understanding how sunlight affects your health will help you get the benefits of sunshine while minimizing the risks.

When sunlight reaches your skin, it triggers your body to make Vitamin D, an important nutrient. However, sunlight also delivers ultraviolet radiation (UV rays) to your skin, and that can lead to sunburn, early wrinkling, and even skin cancer.

There are three main types of UV rays: UVA, UVB and UVC.

UVA rays penetrate deeply into the skin and cause 90% of the damage that leads to premature aging.

UVB rays damage the outer layer of the skin, the epidermis, and cause sunburn. These rays raise the risk for melanoma (the most serious form of skin cancer) more than the other type of radiation.

UVC rays are not currently of too much concern, because the layer of the ozone that circles the earth filters out most UVC rays before they reach the planet’s surface. However, many scientists are concerned that the pollution caused by our modern way of life is reducing the ozone layer. This could pose problems in the future if a reduced ozone layer allows large amounts of UVC rays to reach the surface of the earth.

We get about 75% of our daily UV radiation between 9 a.m. and 3p.m. and about 20% to 30% during the two-hour period between 11 a.m. and 1 p.m. To minimize your exposure to these harmful rays the Canadian Dermatology Association recommends that you reduce the amount of time you spend outdoors between 10 a.m. and 4 p.m. while the sun’s rays are strongest.

The UV Index

The effects of sun exposure add up over time. The more time you spend in the sun during your lifetime, the greater your risk of developing sun-related health problems that may include cataracts as well as skin damage.

To help people determine the level of their sun exposure, Environment Canada developed the UV index, which indicates the intensity of UV radiation. It uses a scale of one to ten, with ten representing the typical midday value in the summertime tropics. The higher the UV index, the faster a person will get a sunburn and the greater the risk of damage. It is based on the approximate amount of time spent in the sun that it would take a fair-skinned person to get a sunburn. People with darker colouring may not burn as quickly, but they still need to take precautions to protect themselves.

The UV Index UV Index Risk Estimated time for a fair- skinned person to burn 0 – 2 Minimal 1 hour 3 – 4 Low Less than 20 minutes 5 – 6 Moderate Less than 15 minutes 7 – 9 High Less than 10 minutes 10 and above Extreme Less than 5 minutes

The UV index tends to be highest in May and June (not July and August as people may think) and on bright days. Low temperatures are no guarantee of safety, because the UV index may actually be quite high even when the temperature is not.

Sunburn and Tanning When skin redness appears right after sun exposure, we call this a sunburn. After about 6 hours, the redness begins to intensify and usually reaches a peak in about 24 hours. The sunburn will eventually begin to fade, but the underlying damage can be lasting.

Depending on the skin type, people may be more likely to develop a tan rather than a sunburn. Some people mistakenly believe that a tan protects them from sun damage. In fact, a tan is a sign that damage has occurred. Any discoloration of the skin is a sign of damage. This is true whether the tan comes from a natural source (the sun) or an artificial one (such as a tanning booth, tanning bed, or sun lamp).

Preventing Sun Damage

Preventing a health problem is always better than treating it, and there are some steps you can take to protect yourself from damage caused by UV rays. The following tips will help:  Limit the amount of time you spend outdoors between the hours of 10 a.m. and 4 p.m.  If you must be outside during these hours, try to stay in the shade. If there is no natural shade, create your own with an umbrella.  Choose a sunscreen with a sun protection factor (SPF) of 15 or higher that protects against both UVA and UVB rays. Use it every day, all year long, and follow the package directions carefully. Many people cheat themselves out of the protection they should be getting because they use too little of the product to get full protection. Some sunscreens need to be applied 20 minutes before the skin is exposed to the sun.  If you are pregnant or taking birth control pills, use a sunscreen with an SPF of at least 30 that provides both UVA and UVB protection.  Use a lip balm that provides UVA and UVB protection to protect the delicate skin on your lips.  Wear a wide-brimmed hat and clothing that covers your arms and legs.  Select sunglasses that provide UVA and UVB protection.  Some medications increase the risk for sunburn. If you are not sure if you medicines are in this category, ask your pharmacist.

Children and the Sun

Children under six months of age should NEVER be exposed to direct sunlight. After that, they should be protected from the sun as much as possible. When choosing a sunscreen for a child, select one that does not contain alcohol, because lotions and gels containing alcohol may cause stinging, burning, and irritation of the skin and eyes. You can help protect the nose, cheeks, and other areas that get the most sunlight by applying a sunscreen that contains a physical sunblock such as zinc oxide. Always use a lip balm with SPF of 15 on the child’s lips. And make sure the child wears a hat with a brim and clothing that covers the arms and legs. For teens and others with acne, select an oil-free sunscreen formula, and don’t forget the SPF 15 lip balm.