Sunscreens are graded with a sun protection factor (SPF), a laboratory measure that assesses its ability to filter out harmful rays. The sun protection number suggests how long your skin will be protected against sunburn compared to being out in the sun without any sunscreen. The higher the SPF number, the more protection you should get. For example, SPF 20 means you can spend 20 times as long in the sun than if you were unprotected before getting sunburned.
People do not use enough sunscreen – there is an internationally agreed application thickness of 2 mg per square centimetre of skin surface, meaning a full body needs at least 35ml. In practice, people usually apply less than half the amount they need or miss out on covering some part of the body, or both. When this is combined with overexposure to the sun, they end up getting sunburned.
Make sure you buy a sunscreen which offers broad-spectrum protection to ward off both UVA and UVB rays. Dermatologists recommend at least SPF 20 products.
People should not totally depend on sunscreens, as they don’t necessarily prevent the occurrence of skin cancer. Therefore, it is still a good idea to stay out of the sun at midday and to protect yourself with a wide-brim hat and adequate clothing.
The sun beams its energy to the earth in rays of heat, namely visible infrared light and invisible ultraviolet (UV) light. The sun’s energy is greatest when it travels through fewer atmospheres. It is more intense closer to the equator, on mountain tops in the summer, and during the middle of the day (from about 10:00 to 15:00).
Two types of ultraviolet light called UVA and UVB reach the earth’s surface. Protective keratin on the skin surface reflects about 10% of ultraviolet light rays before they can enter the skin. UVA and UVB rays bounce off the keratin in much the same way as a mirror reflects light. About half of the UVA that enters the skin penetrates deeply into the skin, but 80% or more of the UVB rays do.
UVB rays – Important info
- Most skin damage is caused by UVB rays
- UVB rays cause pigment cells to multiply so a “tan” results. It also causes thickening, drying and leathering of the skin
- UVB radiation is the main cause of skin cancer
- Maximum protection sunscreens allow no more than 1% of UVB radiation to reach the skin
UVA rays – Important info
- UVA radiation causes the pigment in existing melanocytes to darken so a light, temporary “tan” results.
- About 50% of UVA rays pass through the skin mainly causing premature ageing.
Protect yourself and your family from UV radiation
- Limit direct sun exposure during midday
- Cover up against sun exposure – wear protective clothing
- Wear a hat with wide brim and cover face neck and ears
- Use a sunscreen of SPF 20 or higher
- Wear sunglasses that block UV rays
- Avoid sunlamps and tanning booths
- Check your skin regularly
- Check UV index provided on weather TV reports
Protect your children
By the time child reaches adolescence, nine out of every ten of them will have UV-related skin damage. There is strong scientific evidence that indicates that UV exposure during childhood and adolescence is a major risk factor for developing skin cancer in later life.
Childhood is a critical period during which UV radiation can do the most damage. Often signs don’t appear until later in life and then it may be anything from pigmentation through to skin cancer and from cataracts through to a suppressed immune system.
It only takes a few minutes for a child’s skin to burn and that damage is permanent and cumulative. It has been found that adequate protection (clothing and sunscreens) during childhood can reduce the risks of developing problems later in in life up to 78%. Protection will filter UV rays and help limit the total exposure.
The most damaging effect of the sun is skin cancer. There are different types of cancer:
- Basal Cell Carcinoma
- Most common kind
- Slow growing
- Not life threatening
- Squamous Cell Carcinoma
- Lips, face and tips of ears
- Can spread quickly
- Cure rate of more than 95%
- Malignant melanoma
- Least common but most serious
- Originates in or near a mole
- Growth large and with irregular borders and all age groups are at risk