Written By: Hanan Khalaf. RPHWhat could be the harm of the sun while we are enjoying its warmth?

The main concern about the sun is the invisible form of radiation it sends to us, namely ultraviolet (UVR). This kind of radiation is able to penetrate and change the structure of skin cells leading to various problems, depending on the duration of exposure. Short term exposure leads to acute effects such as burns and blisters. On the other hand long term exposure leads to chronic effects as early aging of the skin with deep wrinkling, risk of photosensitivity, and various forms of skin cancers.

Labels on some eyeglasses indicate they provide protection against UVA & UVB, what does that mean?

This means that there is more than one type of UVR, A, B, & C.
UVA is the most abundant on earth, available throughout the year, and it has the ability to penetrate the human skin deeply causing damage to connective tissue and premature aging.
UVB is less abundant since it is absorbed to some extent by the ozone and it penetrates human skin less deeply compared to UVA. They are known to cause skin burns.
UVC is extremely hazardous, but the good thing it is totally absorbed by the ozone layer.
Accordingly, protection against UVA and UVB is required to get a healthy skin.
How can we protect ourselves and our children from the sun?

Most important ways are:

Avoid outdoor activities during the peak time for UVR as much as possible.Wear protective clothing as tightly knitted, long sleeved, and dark-colored.Eye protection is warranted and can be accomplished using wraparound glasses that provide 100% UVR protection against both UVA & UVB.Apply sunscreens with a SPF of 15 at least to the skin and lips.

What is the peak time for UV rays during the day?
It is estimated that the peak time for UVR during the day is between 10 a.m to 4 p.m. This time might be different from one country to another.

How do sunscreens work?

Chemical sunscreens work by absorbing, reflecting or scattering a certain portion of UVR from your skin to prevent its penetration. Their activity is measured by what is called Sun Protection Factor (SPF). The higher the value, the greater the protection offered by the sunscreen. A value of 15 for example means, if the sunscreen is applied evenly, it will allow you to stay in the sun 15 times longer than you could without the sunscreen.
It is important to remember that sunscreens should be applied at least 30 minutes before going out-door to get the maximum effect.

How can I choose the best sunscreen for me?

The choice of the right type of sunscreen for you depends on several factors as color of the skin, condition of the skin (wet or dry), type of outdoor activity, site of application, and presence of allergic reactions. In general, we can say that fair skin needs SPF of 15 at least while very dark skin needs lower SPF values. When around water or if you sweat profusely, the use of water-proof sunscreen is a good choice, or consider reapplication of the regular preparation. ? If your skin is dry, then lotion or cream will work better for you than gel. Person with known allergies should apply a small amount of the product on a small area of the skin to observe the effects 24hours before using it.
You should follow manufacturer’s recommendation for any reapplication indicated.

Do I need to use sunscreens during summer only?

Sunscreens should be applied during summer even if you are in shade and during winter as well, since UVR can reflect off any surface as sand, concrete, clouds and snow. These reflective surfaces can get you 80% of the sun’s harmful rays.

How important it is to get sun-protection for my kids?

It is very important to make sure that kids are protected from the sun’s rays. This is due to the fact that one-half of persons’ lifetime exposure to UVR occur by the time they are 18 years old. Moreover, studies have shown that severe sunburns during the first 18 years of life can lead to skin cancer later in life.

December 6, 2005.

References:
http://www.cdc.gov/ChooseYourCover/qanda.htm
http://www.surgerydoor.co.uk/coe/skincentre/sun1.shtml
Compendium of Nonprescription products, Canadian Pharmacists Association 2000.