UV Radiation

q8ghrfivc2 For a six billion-year-old star, the sun is certainly in the news a lot lately, mainly because it is still a source of uncertainty and confusion to many of us.

The center of this confusion is the sun’s ultraviolet A (long-wave) and ultraviolet B (shortwave) rays. Our understanding of exactly what kinds of damage each causes to the skin, and how best to protect ourselves, seems to shift every year as new research comes out. For example, it was once thought that only UVB was of concern, but we keep learning more and more about the damage caused by UVA. And new, improved forms of protection against UVA keep emerging. Keeping up with these new developments is a worthwhile challenge that can help all of us prevent sun damage.
What is Ultraviolet Radiation?

UV radiation is part of the electromagnetic (light) spectrum that reaches the earth from the sun. It has wavelengths shorter than visible light, making it invisible to the naked eye. These wavelengths are classified as UVA, UVB, or UVC, with UVA the longest of the three at 320–400 nanometers (nm, or billionths of a meter). UVA is further divided into two wave ranges, UVA I, which measures 340-400 nanometers (nm, or billionths of a meter), and UVA II which extends from 320–400 nanometers. UVB ranges from 290 to 320 nm. With even shorter rays, most UVC is absorbed by the ozone layer and does not reach the earth.

Both UVA and UVB, however, penetrate the atmosphere and play an important role in conditions such as premature skin aging, eye damage (including cataracts), and skin cancers. They also suppress the immune system, reducing your ability to fight off these and other maladies.
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UV Radiation and Skin Cancer

By damaging the skin’s cellular DNA, excessive UV radiation produces genetic mutations that can lead to skin cancer. Both the U.S. Department of Health and Human Services and the World Health Organization have identified UV as a proven human carcinogen. UV radiation is considered the main cause of nonmelanoma skin cancers (NMSC), including basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). These cancers strike more than a million and more than 250,000 Americans, respectively, each year. Many experts believe that, especially for fair-skinned people, UV radiation also frequently plays a key role in melanoma, the deadliest form of skin cancer, which kills more than 8,000 Americans each year.
UVA

Most of us are exposed to large amounts of UVA throughout our lifetime. UVA rays account for up to 95 percent of the UV radiation reaching the Earth’s surface. Although they are less intense than UVB, UVA rays are 30 to 50 times more prevalent. They are present with relatively equal intensity during all daylight hours throughout the year, and can penetrate clouds and glass.
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UVA, which penetrates the skin more deeply than UVB, has long been known to play a major part in skin aging and wrinkling (photoaging), but until recently scientists believed it did not cause significant damage in areas of the epidermis (outermost skin layer) where most skin cancers occur. Studies over the past two decades, however, show that UVA damages skin cells called keratinocytes in the basal layer of the epidermis, where most skin cancers occur. (Basal and squamous cells are types of keratinocytes.) UVA contributes to and may even initiate the development of skin cancers.

UVA is the dominant tanning ray, and we now know that tanning, whether outdoors or in a salon, causes cumulative damage over time. A tan results from injury to the skin’s DNA; the skin darkens in an imperfect attempt to prevent further DNA damage. These imperfections, or mutations, can lead to skin cancer.

Tanning booths primarily emit UVA. The high-pressure sunlamps used in tanning salons emit doses of UVA as much as 12 times that of the sun. Not surprisingly, people who use tanning salons are 2.5 times more likely to develop squamous cell carcinoma, and 1.5 times more likely to develop basal cell carcinoma. According to recent research, first exposure to tanning beds in youth increases melanoma risk by 75 percent.
UVB
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UVB, the chief cause of skin reddening and sunburn, tends to damage the skin’s more superficial epidermal layers. It plays a key role in the development of skin cancer and a contributory role in tanning and photoaging. Its intensity varies by season, location, and time of day. The most significant amount of UVB hits the U.S. between 10 AM and 4 PM from April to October. However, UVB rays can burn and damage your skin year-round, especially at high altitudes and on reflective surfaces such as snow or ice, which bounce back up to 80 percent of the rays so that they hit the skin twice. UVB rays do not significantly penetrate glass.

Suncare on the Slopes

Higher altitude means increased levels of harmful UV exposure compared to sea level areas. UV exposure increases 8-10 percent with every 1,000 feet above sea level. At an altitude of 9-10,000 feet, UV may be 45-50 percent more intense than at sea level. In addition, snow reflects about 80 percent of the UV light from the sun, meaning that you are often hit by the same rays twice. This only contributes to the problem, further increasing the risk for skin cancer.

The combination of higher altitude and ultraviolet (UV) rays reflected by the snow puts skiers and snowboarders at an increased risk of sun damage and ultimately, skin cancer. More than 90 percent of all skin cancers are caused by sun exposure. It’s easy to associate winter with frostbite and windburn, but most people are unaware that UV rays can be even more damaging on the slopes than on the beach,it’s important to take proper precautions while on the slopes.

Both snow and strong wind can wear away sunscreen and reduce its effectiveness, so you have to take extra precautions. To protect your skin from the bitter cold, heavy winds and winter sun, follow these important sun protection tips:
• Use a broad-spectrum sunscreen with an SPF of 15 or higher whenever you spend time outdoors. Apply 30 minutes before hitting the slopes.Be aware that the sun’s reflection off the snow is strong even on cloudy days.
• Apply sunscreen liberally and evenly to all exposed skin – most skiers and snowboarders do not use enough sunscreen and therefore do not get the maximum protection.
• Use a more moisturizing sunscreen. Winter conditions can be particularly harsh on the skin.
• Be sure to cover often-missed spots: lips, ears, around eyes, neck, underside of chin, scalp and hands.
• Always wear a lip balm with an SPF 15 or higher. Lips are even more sensitive than most parts of the skin.
• Reapply at least every two hours, and more often after sweating or exposure to wind and snow.
• Carry a travel-sized sunscreen and lip balm with you on the slopes. Reapply on the chairlift, especially after a long, snow-blown run.

Cover up.

• Wear items like ski masks, which will cover most of the skin, leaving very little exposed to the wind and sun.
• UV-blocking sunglasses or goggles that offer 100% UV protection and have wraparound or large frames protect your eyelids and the sensitive skin around your eyes, common sites for skin cancer and sun-induced aging. The sun’s rays and glare can impair your vision, so it’s important to wear sunglasses or goggles to clearly see the terrain. Plus, it will increase your enjoyment and performance while skiing.
Be mindful of time spent in the sun, regardless of the season.
• Keep track of the time you spend in full sunlight. If possible, ski early in the morning and later on in the day, before 10AM and after 4PM. This helps avoid long lines and decreases the amount of time spent outdoors in the most intense hours of sunlight.

• If you are on the slopes for most of the day, take a few breaks indoors to reapply sunscreen.
• Drink plenty of water to avoid dehydration from the sun.
Enjoy the winter season, but be sure to take care of your skin to avoid the damage the cold season can cause.

The first organization in the U.S committed to educating the public and medical professionals about sun safety, The Skin Cancer Foundation is still the only global organization solely devoted to the prevention, detection and treatment of skin cancer. The mission of the Foundation is to decrease the incidence of skin cancer through public and professional education and research.

FAQ on Sunscreens and Sunburns

1. “How Much Sunscreen Should I Apply?”

The average user of sunscreen tends to use significantly less sunscreen than the amount required to achieve the SPF listed on the container.

2. “How Often Should I Apply Sunscreen When I’m Out In The Sun?’”

Many experts recommend that frequent application during sun exposure is required. However, a group of children were tested by spreading on 1 application of sunscreen to one side of their bodies, and four applications to the other.

They then spent 6 hours in the sun. One application provided the same level of protection as four applications, confirming the adequacy of a single daily application of a sunscreen in that situation.

3. “How Long Before Sun Exposure Should I Apply Sunscreen To My Skin?”

As molecules of sunscreen are present in their active state in the sunscreen, sunscreens work immediately upon application. The only reason for application early is to allow absorption into the skin so that the sunscreen is less likely to be washed off, should the person be entering the water. Even so, modern sunscreens are quite resistant to removal from the skin.

4. “Sun Protection Factor (SPF) – What Is It?”

SPF is the ratio of the minimal ultraviolet dose required to produce redness with and without a sunscreen. For example, if it took ½ hour for your skin to become sunburned without any sunscreen, then for a sunscreen that has a 15 SPF rating, you could stay in the sun for 15 times longer (or 7.5 hours) before you get sunburned. This is provided, of course, that you’ve applied the sunscreen properly so that you’re getting the prescribed protection.

5. “Reactions To Sunscreens?”

Sunscreens can be both an irritant and an allergen, though allergic reactions are rare. Irritant reactions, however, abound. One classic error in sunscreen application is to put a large amount of sunscreen on the forehead. Perspiration and gravity can cause the sunscreen to migrate down your forehead into your eyes, causing a stinging sensation. Some people attribute this to an allergic reaction and discontinue use. It’s also important to wash your hands after applying sunscreen, since rubbing your sunscreen covered finger near your eyes can induce an irritant reaction.

6. “Why Is It Important To Use Sunscreens During Childhood?”

It appears that a great deal of time can elapse between actual sun damage and the development of skin cancer or other skin problems like photoaging. Therefore, it is important to protect your skin from an early age when you are out in the sun.

7. “Sunscreens And The Elderly?”

Many elderly people can become quite obsessed by sun avoidance, and their quality of life can suffer. Sometimes, if they are diagnosed with an actinic keratosis or basal cell carcinoma, they can become anxious and almost leap from shadow to shadow. However, few of them are likely to develop new skin cancers from present sun exposure. As long as they are prudent about avoiding excessive sun exposure and protecting their skin to prevent sunburn, they can continue to enjoy time outdoors.

8. “Can Sunscreens Prevent Cancer?”

There is clear evidence that sunscreens are helpful in preventing actinic keratoses, which are warty lesions that can occur on sun-exposed skin of the face or hands. Research has shown that these lesions can develop into a cancer called squamous cell carcinoma, and that this is linked to a cumulative exposure to the sun.

However, there is surprisingly little evidence that sunscreens have much effect in preventing another kind of skin cancer called basal cell carcinoma, or for malignant melanoma. For malignant melanoma and for basal cell carcinoma, the character and timing, that is, the type of sunlight and your age at the time of the exposure to the sun appears to be more important than the cumulative dose.

Adapted from an article by David I. McLean, MD, and Richard Gallagher, MA.

Essential Oils

An essential oil is a concentrated, hydrophobic liquid containing volatile aroma compounds from plants. They are also known as volatile or ethereal oils, or simply as the “oil of” the plant material from which they were extracted, such as oil of clove. An oil is “essential” in the sense that it carries a distinctive scent, or essence, of the plant. Essential oils do not as a group need to have any specific chemical properties in common, beyond conveying characteristic fragrances. They are not to be confused with essential fatty acids.

Essential oils are generally extracted by distillation. Other processes include expression, or solvent extraction. They are used in perfumes, cosmetics and bath products, for flavoring food and drink, and for scenting incense and household.

Various essential oils have been used medicinally at different periods in history. Medical application proposed by those who sell medicinal oils range from skin treatments to remedies for cancer, and are often based on historical use of these oils for these purposes. Such claims are now subject to regulation in most countries, and have grown correspondingly more vague, to stay within these regulations.

Interest in essential oils has revived in recent decades, with the popularity of aromatherapy, a branch of alternative medicine which claims that the specific aromas carried by essential oils have curative effects. Oils are volatilized or diluted in a carrier oil and used in massage, diffused in the air by a nebulizer or by heating over a candle flame, or burned as incense, for example.

aromatherapy: aro·ma·ther·a·py – noun – The use of volatile plant oils, including essential oils, for psychological and physical well-being.

A few drops of essential oils in your homemade face masks, lotions and sea salts can turn an ordinary mask or treatment into a spa-like experience. But figuring out which essential oils work best on skin types can be confusing. Below is a good list to get your started with the most popularly-used oils to get you started.

Essential Oils by Skin Type

You can find these by capsules in health food stores or in bottles with droppers

Normal skin

Atlas cedarwood, geranium, jasmine, lavender, soy, neroli, evening primrose, almond, orange, geranium, palmarosa, roman chamo, rose, rosewood, Ylang-ylang, tea tree

Combination skin

Geranium, rosewood, Ylang-ylang, rose geranium hydrosol, neroli hydrosol

Dry and aging skin

Almond, carrot seed, cedarwood, clary, jasmine, geranium, lavender, orange, Palma rose, neroli, castor, extra virgin, wheat germ, sandalwood, rosewood, rose, Vetiver, Ylang-ylang

Oily skin

Cedarwood, geranium, Clary, lavender, Ylang-ylang, lemon, peppermint, Niaouli, Cajeput, cypress, frankincense, patchouli, Roman & German chamos, sandalwood, juniper, Melisa, coriander, lime (distilled), grapefruit,rose, rosemary, eucalyptus, red mandarine, myrtle, neroli

Sensitive skin

Roman & German chamomile, rose, Palma Rosa, Helichrysum, neroli, rosewood, carrot, angelica, jasmine, Neroli, Chamomile or Yarrow Hydrosols