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Sunshine,
although essential for health and well being, is certainly a hazard for the
skin. For many people it feels good to spend time outdoors and this makes it
difficult to avoid excessive exposure to the sun. Most of the sun exposure we
accumulate throughout our lives, is thought to be the effect of multiple short
periods of time outside. If the ozone depletion continues this may also increase
our lifetime exposure. Exposure to the
sun also
causes moisture depletion and dries out the skin. Therefore, it is essential to
step-up
moisturisation, when you have been out of doors for a long time.
Sun damage of the
skin, also known as photo damage can be either acute, as in a
sunburn or
more commonly, chronic, seen as gradual changes in the skin caused by an
accumulation of sun exposure throughout one's life. Chronic photo damage results
in either a cosmetic change in the skin's appearance called photo aging, or
changes that are of medical and
health concerns such as pre-cancerous lesions
and
skin cancers. The evidence is very strong that ultra-violet light is the
cause of most of the changes that we consider to be associated with
aging of the skin.
The sun continually produces UV radiation: UV-A and UV-B rays reach the earth
and are a major cause of
skin damage
like skin aging,
sun-burn, immune suppression, and even skin cancer. There are two types of
ultraviolet rays, UVA and UVB. UVA rays penetrate the skin deeply and can cause
melanoma in susceptible people. UVB rays, which don't penetrate as deeply, cause
sunburn and
wrinkling. Most UVB rays are absorbed by sunscreens, but only about half the UVA
rays are absorbed. Ultraviolet (UV) rays are the primary cause of skin cancer.
The skin has a defense mechanism against
sun-damage,
in the form of melanin. The production of melanin is accelerated on
sun-exposure.
However, we have seen that this defense is not enough. That is why protection of
the skin, with ingredients that block the sun's radiation damage, is so
essential. These sun-block agents are incorporated into 'sunscreens'.
It is very important to protect your skin
during exposure to the sun, because of the risk of skin cancers. Long-term
sun exposure
also causes premature ageing, where the skin becomes less elastic and wrinkles
develop. Using the proper
skin protection products can help prevent sun damage. The two main ways of
protecting the skin today are applying a sunscreen lotion to the exposed areas
or simply covering the skin with a garment.
Good sun care
includes:
-
trying to stay out of the sun between 11am
and 4pm during summer;
-
wearing a protective hat, sunglasses,
clothing and lip screen;
-
using sunscreen to prevent
skin burning;
-
Use
sun care
products.
Sun protection
factor (SPF)
Sunscreen SPF is the ‘Sun Protection Factor’ and relates to the amount of
absorption of ultraviolet rays type B (UVB). The
SPF indicates
theoretically how long you may stay in the sun before burning. If your
‘burn-time’ without sun protection is 10 minutes, then a Factor 15 product could
allow you to stay in the sun for 150 minutes (15 min x 10) or 2 hours 30
minutes. However, you should really reapply sunscreen during this time. The burn
time differs for different skin types.
Sunscreen
products
Cream-based
sunscreens tend to be more resistant to removal by water than alcohol-based
products. ‘Water-resistant’ products retain their
sun protection
for at least 40 minutes in water. However, you should be aware that oily
products may prevent the evaporation of perspiration, which can increase the
risk of over-heating, especially in humid conditions. People with acne should
also avoid oil-based products as these could worsen such
skin problems.
While overexposure to the sun is harmful, even
fatal, no exposure means the body can't manufacture vitamin D , which is the
only vitamin whose biologically active form is a hormone. Vitamin D is produced
in the skin from the energy of the sun's UV rays. People at risk for vitamin D
deficiency include alcoholics, non-milk drinkers, and those who do not receive
much sunlight,
especially those who live in regions that get little natural light. Despite the
obvious dangers of unprotected
sun exposure,
we do need some contact with sunlight as it helps with the production of vitamin
D. This is an essential vitamin that plays a number of important roles,
including helping regulate the amount of calcium and phosphate in the body,
which is needed to help keep our teeth and bones healthy. |
