Sunburn
Sunburn is acute inflammation of the skin that follows excessive exposure to UV radiation.4 UV radiation damages DNA in skin cells, resulting in redness of the skin and death of skin cells.4 Sunburn can occur within 15 minutes, and the damage that is caused is permanent, irreversible and adds up with each exposure to the sun.1
Factors that influence sunburn include:4
- Wavelength: shorter UVB rays are the principal cause of sunburn
- Skin type/pigmentation: people with darker skin require 3-5 times more UV exposure than those with lighter skin to cause sunburn
- Hydration: moist skin burns more easily than dry skin
- Reflection: UV rays are reflected off surfaces, snow, ice and sand – sunburn can occur in the shade!2
- Ozone: decrease in ozone layer means less UV rays are filtered out
- Altitude and latitude: UV exposure is greater at higher altitudes and closer to the equator
- Time of day: UV exposure is greater from 10 am to 4 pm
- Season: UV exposure is greater during summer than in winter
- Cloud cover: clouds absorb only about 10 % of UV radiation – sunburn can occur when it is overcast!1,2
Skin cancer
Did you know that South Africa has the second highest incidence of skin cancer in the world?1 This is because of our geographic position and year-round exposure to high UV radiation.5 And everyone, regardless of racial or ethnic group, is at risk.1
Although people with darker skin are at lower risk, their skin cancer is often diagnosed at a more advanced stage and tends to occur on the palms, soles of the feet and mucosal surfaces.5
Other effects of sun exposure include:2
- Early ageing: time spent in sun makes our skin age faster than normal, causing wrinkles, leathery skin and dark spots6
- Lowered immune system: overexposure to the sun can suppress our immune system6
- Eye injuries: UV rays can damage our eyes by burning the cornea and causing cataracts6
How quickly do you burn in the sun?
Type | Description | Skin tone |
---|---|---|
I |
Pale white skinExtremely sensitive skin, always burns, never tansExample: Red hair with freckles |
|
II |
White skinVery sensitive skin, burns easily, tans minimallyExample: Fair-skinned, fair-haired Caucasians, Northern Asians |
|
III |
Light brown skinSensitive skin, sometimes burns, slowly tans to light brownExample: Darker Caucasians, some Asians |
|
IV |
Moderate brown skinMildly sensitive, burns minimally, always tans to moderate brownExample: Mediterranean and Middle Eastern Caucasians, Southern Asians |
|
V |
Dark brown skinResistant skin, rarely burns, tans wellExample: Some Hispanics, some Africans |
|
VI |
Deeply pigmented dark brown to black skinVery resistant skin, never burns, deeply pigmentedExample: Some Hispanics, some Darker Africans |