Health Topics

Healthy Living

April 2012
Everything You Wanted To Know About Sunscreens
Dr Simon Soin
The use of a good medicated sunscreen is an indispensable but often neglected part of a standard daily skin care regimen. Sunscreen use is even more critical in the Indian climate where the skin is exposed to strong sun throughout the year. Read on to dispel the common doubts surrounding the use of sunscreens to help you attain youthful, healthy skin.

What are sunscreens and how do they help my skin?

Sunscreens are chemical or physical agents, that absorb or deflect the harmful UV rays present in incident sunlight, thus preventing photo-damage and photo-ageing of skin. UVA rays cause uneven pigmentation and skin ageing. UVB rays cause tanning, sunburns and skin cancers. Good sun protection prevents the signs of photo-ageing such as wrinkling, sun spots, uneven texture, pigmentation and mottled appearance. There is also a well-established link between some common types of skin cancer and sun exposure, thus sun protection is vital.

Who needs to use a sunscreen?
Everyone over the age of six months needs a daily sunscreen. It is important to inculcate good habits and awareness about sun protection at a young age. Early adoption of sun protection habits preserves youthful skin and prevents premature ageing and sun-linked skin cancers.

How do I select a good sunscreen?
Broad spectrum sunscreens of SPF 15 or higher should be used. These protect against both UVA and UVB rays. Water resistant sunscreen lotions and sprays are also available, which are not washed off during sweating, swimming or other sports.

Various medicated sunscreens are available which are specifically tailored to the needs of different skin types as well as sensitive, acne prone skin or damaged skin. It is a common myth that sunscreen use may aggravate acne. This is false. A medicated non-comedogenic gel based sunscreen limits further damage and pigmentation in acne prone skin.

What does SPF mean?
SPF or Sun Protection Factor indicates the ability of a sunscreen to protect the skin against UVB radiation. It is the ratio of the minimal dose of radiation which produces redness in protected and unprotected sunscreen. Thus a sunscreen of SPF 15 implies that someone who usually gets sunburnt in 30 minutes can stay in the sun without getting burnt for 7.5 hours, after properly applying a sunscreen of SPF 15.

A product of SPF 15 blocks approximately 93 per cent of all incoming UVB rays, while SPF 30 blocks 97 per cent and SPF 50 blocks 99 per cent of the UVB rays.

What is the correct way to use a sunscreen ?
Take a generous pump of sunscreen on your palm and dot over the face, neck and other exposed areas with a fingertip. Gently blend into the skin, coating all exposed areas. Sunscreen should be applied every morning at least 20 minutes before stepping outdoors and reapplied after any sports activities or four hours after the previous application.

Make up should be applied a few minutes after the application of sunscreen. Moisturizers and medicated creams or gels should be applied on the clean face, allowed to dry and followed by use of sunscreen. Lip balms containing sunscreens of SPF 15 or higher are recommended.

If I use a good sunscreen daily is that enough to prevent all sun damage?
For total sun protection one must limit any avoidable sun exposure, seek shade when possible and use a daily sunscreen. In addition, one must use long sleeved clothing, sunglasses and wide brimmed hats. Avoid being outdoors when sunlight is most intense
(between 10 am and 5 pm) and on days with high UV index (measured daily for a location). The presence of water, snow, sand, or reflective glass in the vicinity intensifies the UV rays by reflection, thus necessitating extra care for sun protection. Tanning beds and sunbathing, often popular among light skinned individuals, should be completely avoided.

I work indoors all day. Do I still need to use sunscreens?
Window glass allows the entry of some UV radiation indoors. UV lamps used in modern indoor lighting, laptops and similar devices also emit harmful UV radiation. Thus it is imperative for everyone to use a sunscreen daily.
Will using a sunscreen cause a Vitamin D deficiency in my body?
Adequate Vitamin D can be obtained by consuming a balanced healthy diet. Furthermore, sunshine over any small area such as the exposed hands and feet is adequate for the synthesis of Vitamin D in the body. Sunscreen use does not cause any vitamin deficiency.
Dr Simal Soin is Consultant Dermatologist Indraprastha, Apollo Hospitals,
New Delhi
  • The information on this site does not constitute medical advice and is not intended to be a substitute for medical care provided by a physician.
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