Sun and skin

What is meant by “skin types”?
People with lighter skin types burn more easily than those with darker skin types. Skin types are commonly classified into six categories:

1. Burns very easily, rarely or never tans.
2. Burns easily, tans slowly.
3. Burns moderately, tans gradually.
4. Rarely burns, tans very well (Mediterranean skin types).
5. Never burns, naturally dark skin (Asian skin types).
6. Never burns, naturally very dark skin (African skin types).

What is the difference between natural sunlight and a tanning bed?
Sunlight consists of infrared light (perceived as warmth), visible light, and ultraviolet (UV) light. The UV spectrum is divided into three types based on wavelength: UVA (400–320 nm), UVB (320–290 nm), and UVC (290–200 nm).

• Shorter wavelengths are more harmful to the skin.
• UVC is the most harmful but is entirely filtered out by the ozone layer.
• UVB penetrates the epidermis, while UVA reaches the dermis.

Natural sunlight is composed of more than 95% UVA and a small proportion of UVB. Tanning beds primarily emit UVA with very little or no UVB, meaning they mimic natural sunlight to a large extent.

Is a “healthy tan” truly healthy?
A tanned skin is often perceived as a sign of health, symbolizing time spent outdoors. Historically, pale skin was associated with illness or anemia.
However, when sunlight hits the skin, it causes inflammation and damage to skin cells, including their DNA. Tanning is the skin’s defense mechanism against UV-induced damage. Therefore, a tanned skin always indicates some degree of cellular or DNA damage.
For the skin itself, a “healthy tan” is not genuinely healthy.

Does using a tanning bed before a holiday prevent sunburn?
UVA light provides quick tanning by darkening existing pigment (melanin). This is called direct pigmentation, but it lasts only a few hours and offers minimal protection.
More effective protection develops after three days through increased pigment production and faster pigment distribution in the epidermis, caused by UVB exposure. Additionally, UVB light thickens the epidermis, offering extra protection.
Since tanning beds emit mainly UVA and almost no UVB, they do not protect against sunburn.

Do you need to burn first before tanning?
Sunburn from prolonged exposure is mainly caused by UVB light, which is why most sunscreens include UVB filters.

• UVA rays are less likely to cause burns but still stimulate pigment cells, resulting in tanning.
• Fair-skinned individuals (skin types I, II, and some type III) often redden before tanning.
• Only darker skin types tan without signs of burning.

Fair-skinned individuals usually need to burn slightly before achieving a tan.

Can you get sunburned on cloudy days or under an umbrella?
Approximately 80% of UV rays penetrate clouds, making it easy to get sunburned even in cloudy weather.
A beach umbrella blocks 40–50% of UV rays, with the remainder reaching the skin through reflection and scattering. Some parasol fabrics (e.g., nylon) also let UVB through.
Thus, the skin can burn even on cloudy days or under an umbrella.

What is the effect of snow, water, and sand on sunburn risk?
Snow, water, and sand reflect sunlight (snow up to 80%, sand about 20%), increasing UV exposure and speeding up sunburn.

• In high altitudes, thinner air increases the risk of burning.
• Sunscreen with a much higher SPF is recommended in mountains or at the beach (e.g., 2–3 times higher than at sea level).
• Swimming also exposes the skin to UV, as sunlight penetrates clear water. Sunscreen can wash off in water, reducing protection.

Snow, water, sand, and mountain environments all heighten the risk of sunburn.

What are the harmful effects of (artificial and natural) sunlight?
Immediate effects:

• Excessive UV exposure can cause sunburn, with redness, pain, and sometimes blisters. This is mainly due to UVB radiation.

Long-term effects:

1. Skin Cancer: Repeated or excessive UV exposure increases the risk of skin cancer.
2. Photoaging: UVA damages the skin’s elastic tissue in the dermis, leading to thicker, stiffer skin with deep wrinkles, yellow discoloration, and uneven pigmentation.
   • Light-skinned individuals are most susceptible.
3. Eye damage:
   • Acute damage includes snow blindness (corneal inflammation).
   • Long-term exposure may cause cataracts (lens clouding).

How can you protect yourself from the sun?

• Avoid direct, intense sunlight, especially between 11:00 AM and 3:00 PM.
• Wear protective clothing, such as wide-brimmed hats and long sleeves made from tightly woven fabric.
• Use high-quality sunglasses that block both UVA and UVB rays.

Are sunscreens sufficient to stay in the sun longer?
Sunscreens are not meant to extend sun exposure but to provide extra protection when sunlight cannot be avoided.

• The SPF indicates how much longer you can stay in the sun without burning.
• Sunscreens primarily block UVB, and only some offer UVA protection, which is often less effective.

Apply sunscreen generously (around 35ml per application) and reapply regularly, especially after swimming or sweating. Even with sunscreen, avoid prolonged sun exposure.

How should babies and children be protected?

• Babies under 6 months: Keep out of direct sunlight and avoid sunscreen use. Use clothing and umbrellas for protection.
• Children over 6 months: Follow adult sun protection rules, with additional focus on watertight sunscreen with SPF 15 or higher.

Do sunscreens protect against skin cancer and aging?
Sunscreens reduce UV exposure and thus lower the risk of skin cancer and photoaging but cannot eliminate these risks entirely.

Does UV light have any benefits?
UV light is used to treat certain skin conditions like eczema and psoriasis.
Sunlight also promotes vitamin D production, necessary for strong bones. Moderate exposure is beneficial, but overexposure causes damage.