Sunscreens, UVB and UVA Rays

With summer lurking just around the corner, it’s almost time to tie up that new bathing suit, fire up the grill, and most importantly, slather on the sunscreen. The importance of sun care escalates as knowledge of skin cancer increases in the United States, and the National Cancer Institute estimates that there are more than one million new cases of skin cancer in 2009 alone. Still, loyal sunbathers and frequent beach-goers are able to enjoy some fun in the sun thanks to the vast array of sunscreen available. Sunscreens are available in several forms, including lotion, sprays, ointments, and sticks, and are often labeled with a Sun Protection Factor (SPF), which can range from 2 to 50. The higher the SPF, the more sun protection, and most dermatologists recommend using a sunscreen with an SPF 15 or higher.

Sunscreen protects the skin from harmful UVA and UVB rays from the sun, and too much exposure to these rays can cause sunburn and wrinkles. Long term sun exposure can lead to cancer, which is the most common type of cancer, according to the American Cancer Association. Most sunscreens contain zinc oxide, which as the ability to filter UVA and UVB rays to protect the skin. Zinc oxide has been used in skin products for many years and can be used with all skin types.

UVradiation, a known carcinogen, can have a number of harmful effects on the skin. The two types of UV radiation that can affect the skin—UVA and UVB—have both been linked to skin cancer and a weakening of the immune system. They also contribute to premature aging of the skin and cataracts (a condition that impairs eyesight), and cause skin color changes.

UVA Rays

UVA rays, which are not absorbed by the ozone layer, penetrate deep into the skin and heavilycontribute to premature aging. Up to 90 percent of the visible skin changes commonly attributed to aging are caused by sun exposure.

UVB Rays

These powerful rays, which are partially absorbed by the ozone layer, mostly affect the surface of the skin and are the primary cause of sunburn. Because of the thinning of the ozone layer, the effects of UVB radiation will pose an increased threat until the layer is restored in the latter half of the 21st century.

The following table from the FDA lists these ingredients and includes information regarding the type and amount of ray protection that they provide and their class.

Is a Suntan Healthy?

Just remember, there is no such thing as a healthy suntan. Any change in your natural skin color is a sign of skin damage. Every time your skin color changes after sun exposure, your risk of developing sun-related ailments increases.

Acne Treatments

Acne treatment consists of reducing sebum production, removing dead skin cells, and killing bacteria. Treatment methods differ depending on how serious the acne is. Topical drugs are applied directly to the affected areas of the skin. They are available in the form of creams, gels, lotions, or pads. They are used primarily to treat mild forms of acne in which there is little or no inflammation.

One group of topical drugs used for acne includes antibiotics. These drugs kill the bacteria that contribute to the disease. Another group of drugs is called comedolytics (pronounced KO-mee-do-LIE-tiks). These drugs loosen hard plugs and open pores. Still another group of drugs works by increasing the rate at which new skin cells form. These drugs prevent the formation of new comedos.

Topical drugs are applied once or twice a day after washing with mild soap. Treatment may have to continue anywhere from a few weeks to a few months to a few years. Side effects such as mild redness, peeling, irritation, dryness, and an increased sensitivity to sunlight may occur.

Oral Drugs

Oral drugs are taken by mouth. Doctors sometimes prescribe oral antibiotics for moderate cases of acne. These antibiotics prevent the formation of new comedos and reduce inflammation. They are usually taken once a day
for two to four months. Side effects may include allergic reactions, stomach upset, vaginal yeast infections, dizziness, and tooth discoloration.

A drug that is used for severe cases of acne is isotretinoin (pronounced i-so-TRET-uh-no-un, trade name Accutane). This drug reduces the production of sebum and the stickiness of skin cells. It is used when cysts and nodules are present. The drug may be used alone or with other topical or oral antibiotics.
Isotretinoin treatment usually lasts for four or five months. It is effective in about 60 percent of all patients. If the acne reappears, another course of treatments may be necessary. Some side effects that may accompany the use of isotretinoin include nosebleeds, dry skin, a temporary worsening of the acne, vision disorders, and increased production of liver enzymes, blood fats, and cholesterol. It may also cause birth defects and cannot, therefore, be used by pregnant women.

Women who do not respond to any of these treatments may be given another type of oral drug, an anti-androgen. Anti-androgens reduce the production of androgen and therefore reduce the formation of comedos. Certain types of oral contraceptives are also effective as anti-androgens.

The most serious forms of acne require other types of drugs, including oral corticosteroids, or anti-inflammatory drugs. These drugs are often used for the treatment of a form of acne known as acne fulminans, which occurs mostly among adolescent males. They are also used with acne that produces numerous deep, inflamed nodules that heal with scarring.

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.

Protecting Your Skin From The Sun

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.