Clive Anderson
WE ARE privileged to enjoy fine sunny weather for most of the year. It is almost impossible to live a normal life in our country and not experience significant sun exposure. Unfortunately, like most good things, sun exposure does have a dark side.
The sun emits ultraviolet rays in the form of UVA and UVB. These rays can cause damage to our skin through sunburn, skin photoageing and an increased risk of skin cancer.
The majority of ultraviolet rays reaching the earth's surface are UVA with a small amount of UVB. UVB rays are of shorter wavelength than UVA and affect mostly the outer layers of the skin causing sunburn. UVA rays are of longer wavelength and penetrate more deeply into the skin. It is
the deep-penetrating UVA that causes premature ageing of the skin, wrinkles and sagging.
CHRONIC EXPOSURE
Photoageing is the term used to describe the damage to the skin from chronic exposure to sunlight. The effects of photoageing are most visible on the exposed areas of our body the face and our limbs. These changes are similar to the changes observed in the skin due to chronological ageing, but occur at a much earlier age and at a faster rate. Some of these changes are fine wrinkles, mottling or uneven pigmentation and roughness of the skin.
As adults, we all suffer from photoageing, some more than others. The degree to which we are sensitive to the ageing effect of the sun is determined by our skin phototype.
People with type one skin are at much greater risk for sunburn, photoageing and skin cancer than persons with type V and VI skin. Most Jamaicans belong to type V and VI skin categories, but significant numbers of our kin are type II to IV.
To counter photoageing, two main approaches are recommended:
Firstly practise prevention from childhood by using photoprotective agents when outdoors. Physical photoprotective agents are clothing such as hats, along with umbrellas, awnings and tents. Chemical photprotective agents are sunscreens applied to the skin. Use a broad spectrum sunscreen with a sun protection factor of at least 15. For phototypes I and II, SPF 30 may be more appropriate. There are numerous examples of these sunscreens on our shelves, some combined with good moisturisers that can be applied daily. Early and regular use of these agents will protect the skin from both UVA and UVB rays and reduce photoageing.
For those to whom this advice is too little too late, there are numerous skin rejuvenation treatments that you can discuss with your dermatologist. These include chemical agents that remove the outer damaged layer of skin such as tretinoin, physical procedures such as chemical peels, microdermabrasion and laser rejuvenation. An integral part of any procedure will be the continued use of a sunblock.
Special mention must be made of those persons who move from being skin type VI to skin type IV or V by the persistent application of various bleaching agents. In so doing they significantly reduce their skin's natural protection to UVA and UVB. They have increased their risk of sun damage and in the short term will sunburn more easily. In the long term they will have increased photoageing and an increased risk of skin cancer.
Know your skin phototype and practise good sun sense.
Dr. Clive Anderson is a dermatologist and venereologist; email: yourhealth@gleanerjm.com.
