Derm 101

The Sun and Skin Cancer

Skin cancer is the most common form of cancer in the US. It is estimated that close to 1 million new cases of invasive and non-invasive melanoma, the most deadly form of skin cancer, will occur this year. Studies have confirmed that sun exposure is responsible for the development of at least two-thirds of all melanomas.
The American Academy of Dermatology suggests, regardless of skin type, a broad-spectrum sunscreen with an SPF of at least 15 should be used year-round. Broad-spectrum protects you against UVA and UVB rays. UVB rays, the sun’s burning rays, are the primary cause of sunburn and skin cancer. UVA rays penetrate deeper into the dermis, and are considered to be the chief culprit behind wrinkling, loss of collagen which causes skin sagging and other aspects of photoaging. Studies show exposure to UVA rays not only increases UVB’s cancer causing effects, but may directly cause certain types of melanoma.

Sierra Summits High Altitude Adventure Sunblock is a broad spectrum sunblock, protecting against UVA rays that cause wrinkles and loss of collagen,
as well as the burning UVB rays.

Cover Up
Following these simple rules will help protect you and your family from the sun’s harmful UV rays.
Stay out of the sun between 11am - 3pm, when rays are most damaging
If you can’t avoid the sun, wear closely-woven clothing. Look for clothing with a label stating its UPF (protection factor). Tests have shown sun clothing blocks ultraviolet radiation very effectively. However, normal fabrics are also protective.
Wear sunglasses that provide 99 - 100% UVA and UVB protection. This will greatly reduce sun exposure that can lead to cataracts and other eye damage
Put on a broad-brimmed hat.
Avoid sunlamps and tanning parlors
Apply at least SPF 15 liberally and reapply every 2 hours when working, playing or exercising outdoors.

Rub it in Right
Generously apply to dry skin 30 minutes before going outdoors, particularly the face, ears, and hands. One ounce, enough to fill a shot glass, is considered the amount needed to cover the exposed areas of the body properly. Reapply sunscreens every 2 hours or immediately after swimming or strenuous activity. Sunscreens should have an SPF of 15 or higher that provides broad-spectrum coverage against all ultraviolet light. Look for the ingredients titanium dioxide, zinc oxide, and avobenzone (Parsol 1789).

A Sunblock in the Winter?
Adventure seekers, or anyone outside during the winter months, risk overexposure to the sun.
People assume the winter sun is weaker and less dangerous than the summer sun and therefore do not wear proper sun protection. That’s why it is so important for those living or visiting high altitude areas, to recognize the increase in UV exposure and take extra precautions.

The sun’s reflective powers are great – 17% on sand, but 80% on snow. The risk of developing a sunburn while you’re out enjoying the snow is by far, greater. Also, ultraviolet intensities at altitudes of 8,000 to 11,000 feet have been shown to be 60 - 80% higher than at sea level for the same latitude. That means any skier at Lake Tahoe will receive more than three times the UV exposure necessary for sunburn. Someone with average complexion, not wearing any sun protection, would burn after six minutes of sun exposure on a clear day at 11,000 feet, while the same person would burn after 25 minutes on the beaches in Cape May, New Jersey.

What’s an SPF?
The SPF numbers, or Sun Protection Factor, on the sunscreen’s packaging can range from as low as 2 to greater than 50. These numbers refer to the product’s ability to deflect the sun’s burning rays. The SPF rating is calculated by comparing the amount of time needed to produce a sunburn on sunscreen protected skin to the amount of time needed to produce a sunburn on unprotected skin.
Here’s an Example:
If a sunscreen is rated SPF 2 and a person who would normally turn red after 10 minutes of exposure in the sun uses it, it would take 20 minutes of exposure for the skin to turn red.
2 (SPF) x 10 (minutes) = 20 (minutes)
A sunscreen with an SPF of 15 would allow that same person to stay in the sun for 150 minutes.
15 (SPF) x 10 (minutes) = 150 (minutes)

Derm Speak:
Actinic keratosis (AK): Known as a solar keratosis, it is a small crusty, scaly, or crumbly bump or horn that arises on the skin surface, considered a pre-cancer lesion.
Basal Cells: Small, round cells found in the lower part, or base, of the epidermis, the outer layer of the skin. These cells divide to produce new skin cells, replacing those that die and slough off the surface of the skin.
Basal Cell Carcinoma (BCC): The most common form of skin cancer, affecting 800,000 Americans each year. In fact, it is the most common of all cancers.
Broad-Spectrum: Means it will protect you from UVA and UVB rays
Dermis: The lower or inner layer of tissue that makes up the skin.
Dysplastic nevi: Atypical moles; moles whose appearance is different from that of common moles.
Epidermis: The upper or outer layer of tissue that makes up the skin.
Melanoma: A highly malignant type of skin cancer that arises in melanocytes, the cells that produce pigment. Melanoma usually begins in a mole.
Squamous Cells: Flat cells that make up most of the epidermis, the outer layer of skin; they look like fish scales.
Squamous Cell Carcinoma (SCC): The second most common skin cancer after basal cell carcinoma, affects more than 200,000 Americans each year.
UVA: The ultraviolet rays from the sun that penetrate deep into the dermis. They are considered to be the chief culprit behind wrinkling, leathering, other skin disorders, cancer, and lowered immunity against infection. UVA rays are not absorbed by the ozone layer.
UV index: A daily measure of the strength of the sun's ultraviolet (UV) rays for a region
UVB: The ultraviolet rays from the sun that cause sunburn and skin cancer. UVB rays are partially absorbed by the ozone layer.
SPF: An acronym for Sun Protection Factor. The numbers refer to the product’s ability to deflect the sun’s burning rays.

Visit www.aad.org for more information on skin cancers