Sunburn: Causes, Prevention & Sunscreen Protection for Healthy Skin
what is sunburn?
Sunburn is your skin’s inflammatory reaction to overexposure to ultraviolet (UV) radiation from the sun. When UV rays penetrate the skin, they damage the DNA in skin cells. Your body responds by increasing blood flow to the affected area, causing redness, swelling, and pain.
three bands of ultraviolet rays
Ultraviolet rays are a lower energy ultraviolet which penetrate deep into the dermis where they cause fragmentation of the collagen and elastin fibres which provide the skin with support. Excessive amount of UVA to penetrate into dermis and eventually causing ageing of the skin.
UVB rays penetrate only into the epidermis and they are the rays responsible for sunburn. These rays stimulate the melanocytes in the basal layer of the epidermis to produce melanin resulting in a long-lasting tan and they are chiefly responsible for the formation of skin cancers.
UVC rays are the most harmful type of ultraviolet radiation, but they never reach the Earth’s surface because they are completely absorbed by the ozone layer and atmosphere. Only UVA and UVB rays penetrate through, affecting our skin and health.
beneficial effects
Natural sunshine is beneficial to most people in small doses and it has certain effects.
- Produces tan
- Stimulates the production of vitamin D
- Stimulates the metabolism
- Ultraviolet rays kill some bacteria on the skin
- The shedding of dead skin cells is accelerated and this will vary, depending upon the amount of exposure
When the ultraviolet rays stimulate the cell in the basal layer of the epidermis to produce more rapidly. This creates additional protection for the skin against the ultraviolet radiation. This can cause sunburn. Over exposure to UVA will cause ageing of the skin and UVB may cause skin cancer. Exposure to ultraviolet light should be times when the sun is not high in the sky. It is at its strongest between the hours of 11 am and 4 pm. The skin’s reaction will normally depend upon the skin type. No matter which skin type a person has, the skin will burn if there is over exposure. Several hours after exposure the skin will become red and this reddening is called erythema. Sunburn is an injury to the skin. When the skin begins the normal healing process the cells in the skin divide quickly to form new tissue but if the sunburn was severe then scarring may occur.
types of sunscreens
Physical Sunscreen
This type of sunscreen is an opaque film used on the skin to reflect the ultraviolet radiation. It forms dense barrier but actually blocks perspiration so its use is limited to small exposed areas such as bridge of the nose and the cheekbones.
Chemical Sunscreen
This type of sunscreen can be a water or oil soluble chemical which absorbs ultraviolet radiation reducing its intensity. They come in the form of oil, lotion, cream or milk and some waterproof. Broad spectrum sunscreen which will filter out both ultraviolet A and B rays.
how to use ?
Apply before going into the sun
Reapply during the day
