Risks and Benefits of Sun Exposure

Exposing skin to sunlight presents both health risks and health benefits. Sunlight is the major source of vitamin D-producing Ultraviolet B radiation, which has a wide range of positive health effects, including possibly inhibiting the growth of some cancers. On the other hand, long-term sunlight exposure is known to be associated with the development of skin cancer, skin aging, immune suppression and eye diseases such as cataracts. Sun exposure has also been associated with the timing of melatonin synthesis and reduced risk of seasonal affective disorder. A number of public health organizations state that there needs to be a balance between having the risks of having too much and the risks of having too little sunlight. There is a general consensus that sunburn should always be avoided.

However, not all physicians agree with the assertion that there is an optimal level of sun exposure, with some arguing that it is better to minimize sun exposure at all times and to obtain vitamin D from other sources.

Serum levels of 25(OH) D3 are below the recommended levels for a large portion of the general adult population and in most minorities, indicating that Vitamin D deficiency is a common problem in the United States.
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Benefits

According to the U.S. National Institutes of Health Office of Dietary Supplements, most people in the United States can meet their vitamin D needs through exposure to sunlight, even though a large portion have serum 25(OH)D3 levels below recommendations. Ultraviolet (UV) B radiation with a wavelength of 290-315 nanometers penetrates uncovered skin and converts cutaneous 7-dehydrocholesterol to previtamin D3, which in turn becomes vitamin D3. Season, geographic latitude, time of day, cloud cover, smog, skin melanin content, and sunscreen are among the factors that affect UV radiation exposure and vitamin D synthesis. The UV energy above 42 degrees north latitude (a line approximately between the northern border of California and Boston) is insufficient for cutaneous vitamin D synthesis from November through February; in far northern latitudes, this reduced intensity lasts for up to 6 months. In the United States, latitudes below 34 degrees north (a line between Los Angeles and Columbia, South Carolina) allow for cutaneous production of vitamin D throughout the year.

Complete cloud cover reduces UV energy by 50%; shade (including that produced by severe pollution) reduces it by 60%. UVB radiation does not penetrate glass, so exposure to sunshine indoors through a window does not produce vitamin D. Sunscreens with a sun protection factor of 8 or more appear to block vitamin D-producing UV rays, although in practice people generally do not apply sufficient amounts, cover all sun-exposed skin, or reapply sunscreen regularly. Skin likely synthesizes some vitamin D even when it is protected by sunscreen as typically applied.

The factors that affect UV radiation exposure and research to date on the amount of sun exposure needed to maintain adequate vitamin D levels make it difficult to provide general guidelines. It has been suggested by some vitamin D researchers, for example, that approximately 5-30 minutes of sun exposure between 10 AM and 3 PM at least twice a week to the face, arms, legs, or back without sunscreen usually lead to sufficient vitamin D synthesis and that the moderate use of commercial tanning beds that emit 2%-6% UVB radiation is also effective. Individuals with limited sun exposure need to include good sources of vitamin D in their diet or take a supplement.

Risks

Despite the importance of the sun to vitamin D synthesis, it is prudent to limit exposure of skin to sunlight and UV radiation from tanning beds. According to the National Toxicology Program Report on Carcinogens from the Department of Health and Human Services, broad-spectrum UV radiation is a carcinogen thought to contribute to most of the estimated 1.5 million skin cancers and the 8,000 deaths due to metastatic melanoma that occur annually in the United States Lifetime cumulative UV damage to skin is also largely responsible for some age-associated dryness and other cosmetic changes.

It is not known whether a desirable level of regular sun exposure exists that imposes no (or minimal) risk of skin cancer over time. The American Academy of Dermatology advises that photoprotective measures be taken, including the use of sunscreen, whenever one is exposed to the sun.

Is there a safe level of sun exposure?

According to a recent study submitted by the University of Ottawa to the Department of Health and Human Services in Washington, D.C., there is not enough information to determine a safe level of sun exposure at this time.

There is no consensus on which component of Ultraviolet Radiation (UVA or UVB or UVC) actually is carcinogenic, and the composition of Ultraviolet Radiation changes throughout the day: At high noon, Ultraviolet Radiation reaching ground level is 95% UVA and 5% UVB, while before 10am and after 2pm this percentage changes over time to 99% UVA and 1% UVB. This is caused by the the reflection of UVB rays back into space due to sun angle as the earth slowly rotates on its axis. The rate of change is faster the farther the position moves away from the equator (ie more north or south) 99% UVA / 1% UVB sunlight is known as “bronzing” rays, as it provides the deepest colour tanning.

On average over a day, 98.7% of the ultraviolet radiation that reaches the Earth’s surface is UVA. UVC is almost completely absorbed by the ozone layer and does not penetrate the atmosphere in any appreciable quantities. As a result, only the combination (UVA, UVB, and UVC) known as “Ultraviolet Radiation” is listed as a carcinogen, the components are only “likely to become” known carcinogens. Solar radiation, also known as “sunlight” is also listed as a carcinogen because it contains Ultraviolet Radiation. This means also that the UV Index is a measure of total Ultraviolet Radiation, and not just Vitamin D-producing UVB.

Sunlight is therefore the only listed carcinogen that is known to have health benefits, in the form of helping the human body to make Vitamin D. This makes sunlight unique on the list of known carcinogens.

Homo sapiens evolved near the equator, and human skin color is a visible indication of direct sun exposure due to the pigmentation level. With new evidence of Vitamin D receptors in all body tissues, experts advise having a balance between Vitamin D from sun exposure and Vitamin D from supplements. The only way to quantify adequate levels of Vitamin D is with a serum 25(OH) D3 test.

Sunlight

Sunlight, in the broad sense, is the total frequency spectrum of electromagnetic radiation given off by the Sun. On Earth, sunlight is filtered through the Earth’s atmosphere, and solar radiation is obvious as daylight when the Sun is above the horizon.

When the direct solar radiation is not blocked by clouds, it is experienced as sunshine, a combination of bright light and radiant heat. The World Meteorological Organization uses the term “sunshine duration” to mean the cumulative time during which an area receives direct irradiance from the Sun of at least 120 watts per square meter.

Sunlight may be recorded using a sunshine recorder, pyranometer or pyrheliometer. Sunlight takes about 8.3 minutes to reach the Earth.

Direct sunlight has a luminous efficacy of about 93 lumens per watt of radiant flux, which includes infrared, visible, and ultraviolet light. Bright sunlight provides illuminance of approximately 100,000 lux or lumens per square meter at the Earth’s surface.

Sunlight is a key factor in photosynthesis, a process crucially important for life on Earth.

Life on Earth

The existence of nearly all life on Earth is fueled by light from the sun. Most autotrophs, such as plants, use the energy of sunlight, combined with minerals and air, to produce simple sugars—a process known as photosynthesis. These sugars are then used as building blocks and in other synthetic pathways which allow the organism to grow.

Heterotrophs, such as animals, use light from the sun indirectly by consuming the products of autotrophs, either directly or by consuming other heterotrophs. The sugars and other molecular components produced by the autotrophs are then broken down, releasing stored solar energy, and giving the heterotroph the energy required for survival. This process is known as respiration.

In prehistory, humans began to further extend this process by putting plant and animal materials to other uses. They used animal skins for warmth, for example, or wooden weapons to hunt. These skills allowed humans to harvest more of the sunlight than was possible through glycolysis alone, and human population began to grow.

During the Neolithic Revolution, the domestication of plants and animals further increased human access to solar energy. Fields devoted to crops were enriched by inedible plant matter, providing sugars and nutrients for future harvests. Animals which had previously only provided humans with meat and tools once they were killed were now used for labour throughout their lives, fueled by grasses inedible to humans.

The more recent discoveries of coal, petroleum and natural gas are modern extensions of this trend. These fossil fuels are the remnants of ancient plant and animal matter, formed using energy from sunlight and then trapped within the earth for millions of years. Because the stored energy in these fossil fuels has accumulated over many millions of years, they have allowed modern humans to massively increase the production and consumption of primary energy. As the amount of fossil fuel is large but finite, this cannot continue indefinitely, and various theories exist as to what will follow this stage of human civilization (e.g. alternative fuels, Malthusian catastrophe, new urbanism, peak oil).

Facial Mask Treatments After Sun Exposure

In recent past years people have used masks as skin and facial treatment. Facial mask is a creamy mask applied to clean or smooth the face. It often contains minerals, vitamins, and fruit extracts, such as cactus and cucumber. There are different kinds of masks for different purposes; some are deep cleansing for cleaning the pores. The perceived effect of a facial mask treatment can be revitalizing, rejuvenating or refreshing.

Facial masks are most commonly used by women but are also used by men. Applying mask as your facial treatment should be selected according to your skin type:

For oily skin: use clay and mud masks. Clay is an important element present in the earth that can be mixed with water to form a smooth paste and thereby provide a smooth texture for the skin. Mineral clay heals, improves circulation and makes the skin soft and supple. Mud rich with minerals absorbs excess oil, cleans clogged pores and removes blackheads and deeply embedded impurities.

For dry skin: use cream-based masks. You can try masks made from clay added by honey, yogurt, or milk to smooth skin, moisten, and cleans pores.

For normal skin: choose mask made from oatmeal mixed with white egg and milk as your facial treatment to remove all the dead cells present in the skin and get soften skin.

For getting the best result of this skin care facial mask should used with these following steps:

1. Use mask after cleansing your face.

2. Avoid applying mask on the area around eyes and mouth.

3. Allow to dry for 10-15 minutes. Remove with wet sponge, and wash the skin with cool water.

4. You should not apply mask as your facial treatment everyday. Apply it once or twice a week is enough.

5. Follow those steps with applying toner/astringent and then face moisturizing lotion.

You can do that facial treatment by yourself in your home. Besides for facial treatment, you can use mask as your body skin care treatment. Enjoy your relax time and get healthy, supple, and glowing skin.

Choosing a Perfect Sun Hat for Kids

We all know it is important to have healthy skin. Since more than 1/3 of all skin cancer appears on the face and the number one culprit for wrinkles and premature aging is the sun, wearing a good sun protective hat is a preventative measure too important to miss. A sunburn is never good , but remember sun damage is also cumulative. In other words, UV injury upon injury adds up over time to cumulate into major skin damage. The earlier sun protective measures are started, the better.

Let me say up front that kids can be tough when it comes to hats. Not that they are hard to fit but that getting a child to wear a hat can be a challenge. If you start them off wearing hats from infancy, like a car seat, they may come to expect wearing a sun hat is just a way of life. But even then, we often hear that most kids go through the “There is no way I am wearing a hat” stage. But fear not! As fellow conspirators in your child’s well-being, we think we may have some ideas that make wearing a hat fun!

So let’s start with getting a good fit, and we will end with suggestions that might help you get your children interested in wearing their sun hats.

Getting a good fit: The best way to get a good fit is the old fashion way of measuring the circumference of the head. For some of our hats we include age equivalents but beware! Head size varies dramatically for both adult and children with no regard to age or gender. We have seen 8 year olds with adult size heads. So measure around the head (above the eyes and ears… where the hat brim sits) with a soft measuring tape or use a string and then measure the length of the string to take the guess work out of sizing.

As we all know, kids grow at an alarming rate. Most of our hat measurements are within a range, but if your child’s head measurement is very close to the next larger size, you may want to consider choosing that bigger size.

Our brim sizes are all child appropriate, but you will most likely have insights as to the width of the brim that is best for your child. We would suggest you go with your gut feeling on this one, remembering that the wider the brim, the more sun will be blocked. Additionally, a brim with a downward slope will increase the sun protective ability of the hat.

Unless you know your child has a problem with a chin strap, we would suggest a chin strap to keep the hat on in the wind and when at play. If the hat you choose comes with a unwanted chin strap you can always cut it off or remove it.

So now, how do we get your child to wear a protective sun hat?

Here are some ideas to consider:

1. Young kids want to be like you … just like you. So, one of the best ways to get a child to wear their sun hat is to wear one yourself. Day in and day out don’t go outdoors without your sun protective hat and your child will get the message. And just think of all the benefits your own face will receive!
2. Talk to other parents about the benefits of having their kids wear a hat. Make wearing a hat the “IN” thing to do. When everyone else is doing it, arguments often vanish.
3. Here is our FUN idea – Have your child “design” his/her own hat, and maybe even hats for the rest of the family. Put out paint, fabric cut in daisy shapes, and other fun materials that could augment a hat. We even have a “Paint Your Own Hat” kit if you are tight on time. Another idea is to have a hat painting party and get everybody into it. I’ll bet you did not think sun protection could be fun!

Even In The Winter, You Still Need Sun Exposure Protection

Even in the winter you still need sun exposure protection. The cold of winter can be very deceiving. When you’re shivering in your heavy winter coat and you have long johns on just to stay warm, why in the world would you think of sun exposure protection? Wouldn’t you think that was just for summer?

Not really! The sun will bathe everyone in it’s UV rays in summer or winter, rain or shine. Even in the winter, you’ll still need sun exposure protection.

If you live where it’s sunny all the time then it really goes without saying, you really need to wear sunblock all the time and a good pair of sunglasses to help protect your eyes.

But, even when you live some place where it snows, you still need sunglasses and sunblock. Really you need them even more since the bright snow reflects the UV rays right back at you. So, you end up getting the UV rays right from the sun and from the bright glare of all the snow that is all around you.

So, you may be asking yourself, what is so bad about the UV rays? I have 2 words: free radicals. As you know, we are made up of cells. Molecules are what cells are made of. The molecules that have unpaired electrons are called free radicals. These electrons want to pair up so they can stabilize the molecule. Doing so by taking electrons from any molecule they make contact with. This will make those particular molecules unstable and this makes them turn and make the other molecules unstable. As this is happening in our cells damage occurs.

The opposite are the antioxidants. They give electrons to the free radicals thus neutralizing them, stopping the damage.

The sun’s UV rays make free radicals, this is why more sun exposure protection the better. It’s true that sunlight helps our bodies by producing vitamin D but only about 10 minutes a day is all you need for that. Make sure you use plenty of sunblock so you can protect your body.

Eat foods rich in antioxidants like veggies and fruits. Also the Vitamins E and C have good potent antioxidants so take these supplements to help.

Play It Safe – Wear Sun Hats

The head must be protected from the heat and rays of the sun. If you happen to visit a beach or are out in the open country with a blazing sun, it’s advisable for you to wear a sun hat. A sun hat is not a fashion item, but required health protection. The sun’s rays can cause sun stroke and blisters on your scalp. If a person happens to be bald, their head can sweat profusely in the heat. Appropriate headgear is worn as part of the uniform by the defense forces of the world. This is to protect them from the rays of the sun. Sun rays can also cause skin diseases and skin cancer. Therefore, it is imperative to wear appropriate hats. If you are going to spend time outdoors in the sun, the hat you wear should have a wide brim so that the back of the neck, the forehead, and the ears, and sides of the face are protected from the sun’s rays.

When buying a hat, choose one that is made of a natural fiber such as cotton. There should also be small vents on the side of the hats. Natural fiber is cooler than synthetic fiber, and the vents will allow the flow of air on the scalp. When buying a sun hat, buy one that is of thick material and is white or some light color. White and light colored sun hats do not absorb the sun’s heat. So, they serve as additional protection for the head.

People who live in hot or tropical climates wear some form of headgear to protect their heads from the rays and heat of the sun. They wear it to safeguard their health. There are definite health benefits to wearing sun hats. One major health benefit is that your scalp will not get burnt, and also your chances of suffering from a sun stroke are reduced, and of course, your skin is protected from skin cancer, which may be caused by the ultra violet rays of the sun.

How long or thick your hair may be, it’s still advisable to wear a sun hat whenever you are out in the sun. Even if you are pottering around in the garden, or getting a sun tan, you must wear a sun hat. If you happen to have delicate skin, then it becomes all the more necessary to wear a hat.

So, wearing a proper hat that will protect your head and parts of your face is essential. The sun’s rays can cause serious skin damage. The skin takes a long time to heal from sunburn. So, why take a risk when wearing a hat will protect your head and is also beneficial for your health. In case you are going to a country where the temperatures are high and there is plenty of sunshine, remember to buy and take a sun hat. The biggest organ of the body is the skin and nobody wants to damage their skin.

Overexposure to the Sun Can Happen Indoors and Outdoors

Journal of the American Academy of Dermatology article offers information about the recent development in sun protection provided by window and automobile glass, and sunglasses.

In the car, at work or walking to and from a store, you can’t escape the sun’s ultraviolet (UV) rays. However, new research about the transmission of UV light through window and automobile glass and through sunglasses, has led to developments that can help protect people from the sun.

“People should realize that even during everyday activities they are receiving incidental sun exposure which harms the skin as it accumulates and can result in premature aging, wrinkles and even skin cancer,” said dermatologist Henry W. Lim, M.D., chairman of the department of dermatology, Henry Ford Hospital in Detroit, Mich., and co-author of the Journal of the American Academy of Dermatology article entitled, “Photoprotection by window glass, automobile glass and sunglasses.” “Dermatologists and manufacturers of glass products and sunglasses are continually working to find better ways to decrease the amount of UV radiation being filtered through these items to the skin and eyes. These advances are helping to reduce the amount of UV exposure that a person receives on a daily basis.”

UV radiation from the sun comes in two forms: ultraviolet A (UVA) and ultraviolet B (UVB). UVB has long been associated with sunburn while UVA has been recognized as a deeper penetrating radiation that contributes to premature aging and wrinkle formation. Both of these types of rays have been linked to the development of skin cancer. More than 1 million new cases of skin cancer are diagnosed each year.

Window Glass and Photoprotection

Window glass filters out UVB rays, but UVA rays are still transmitted to the skin through the panes. The type of glass and the type of coating on the glass can affect the percentage of UV radiation that is transmitted to the body.

Most residential buildings have one of three types of glass: clear, tinted or reflective. Of these three, reflective glass, the kind that eliminates the ability to see the interior of a building from the outside during the day, minimizes unwanted solar heat gain and reduces UV transmission to less than 25 percent. This means nearly one-quarter of the UV exposure, exclusively the longer wavelength UVA, is reaching the inside though, remarked Dr. Lim.

“Most Americans spend 80 percent of their day indoors at work or school,” stated Dr. Lim. “With the new trend in architecture toward more and larger windows in buildings, protection from UV exposure when indoors has become an important issue for not only the cost-effectiveness of cooling a building, but also for the health and safety of the employees who work within it.”

Recent developments in window glass include low-emissivity (low-E) glass which has a special surface coating between layers of antireflective glass. This type of glass reflects up to 70 percent of solar heat and reduces UV transmission through the panes to 20 percent.

To protect the skin from the damaging rays of the sun when working indoors, it is important to: arrange workspace so that the body is not in direct sunlight; and use blinds or shades on the windows during peak sun hours.

Automobile Glass and Photoprotection

In studies of UV exposure in cars, it was shown that the parts of the driver’s and passenger’s bodies closest to the window received the greatest UV exposure. Side and rear windows are usually made from non-laminated glass, allowing a significant amount of UVA to pass through to the passengers in the car. Most windshields are made from laminated glass, the type of glass designed to prevent fragments from shattering onto the occupants during an accident and which can filter both UVB and a large portion of the UVA rays.

Tinting automobile glass is an option that allows 3.8 times less UVA light to be transmitted to the interior of the car as compared to untinted window glass. In a 2004 study of UV transmission and color tint, grey tinted laminated glass provided the highest UV protection with only 0.9 percent of UVA light transmitted versus 62.8 percent transmitted through non-laminated clear glass. People who are considering tinting their windows should take their car to a professional auto detailing shop, in order to ensure that the tinting meets the federally mandated 70 percent of minimum visible light transmittance through the windshield.

“Obviously UVA exposure in a car is influenced by non-glass-related factors such as position of the individual in the vehicle, direction of travel with respect to the sun, and time of day,” stated Dr. Lim. “However, the more time a person spends in a car, especially at the same time of day such as during a regular commute, can greatly affect the amount of UV exposure their skin receives.”

To reduce sun exposure while driving, wear protective clothing, such as a long-sleeved shirt and pants, especially when the body is in the sun; apply sunscreen generously to any exposed skin before driving, especially the hands, forearms and face; and wear protective sunglasses to reduce glare and protect the eyes from UV exposure.

Sunglasses and Photoprotection UV radiation is potentially hazardous to the structure of the eyes, particularly the cornea, lens and retina, which is why the U.S. developed a “sunglass standard,” with the latest version published in 2001. Sunglasses are classified into three categories: cosmetic sunglasses providing minimal UV protection; general purpose sunglasses designed to reduce glare in bright light or when driving; and special purpose sunglasses for activities such as skiing or going to the beach.

“The ideal sunglasses should substantially reduce UV exposure of the cornea and the lens, including any UV coming from lateral directions, and should wrap around the eyes, thereby maximizing eye and eyelid protection,” said Dr. Lim. “For even better protection, wear a broad-brimmed hat which can help reduce the level of UV radiation reaching the eyes and the surrounding area.”

In addition, Dr. Lim recommended the following tips when purchasing sunglasses to maximize UV protection:

Look for neutral gray and amber brown lenses that give true color rendition, particularly to red and green stoplights. Seek glasses with a large frame and lenses that cover the entire eye and wrap around the side of the eye.

Look for the “100% UV Protection” sticker to ensure that the sunglasses meet standards for safe levels of UV protection.

Expensive sunglasses do not necessarily provide better UV protection, according to Dr. Lim. Darkly tinted sunglasses can make pupils dilate and increase lid opening, thereby resulting in increased UV exposure to the lens of the eye.

In addition to wearing sun protective clothing, including sunglasses, you should follow these sun protection tips and Be Sun SmartSM:

Generously apply sunscreen to all exposed skin using a Sun Protection Factor (SPF) of at least 15 that provides broad-spectrum protection from both ultraviolet A (UVA) and ultraviolet B (UVB) rays. Re-apply every two hours, even on cloudy days, and after swimming or sweating.

Seek shade when appropriate, remembering that the sun’s rays are strongest between 10 a.m. and 4 p.m.

Use extra caution near water, snow and sand as they reflect the damaging rays of the sun which can increase your chance of sunburn.

Protect children from sun exposure by applying sunscreen. Get vitamin D safely through a healthy diet that includes vitamin supplements. Don’t seek the sun.

Avoid tanning beds. Ultraviolet radiation from the sun and tanning beds causes skin cancer and wrinkling. If you want to look like you’ve been in the sun, consider using a sunless self-tanning product, but continue to use sunscreen with it.

Check your birthday suit on your birthday. If you notice anything changing, growing, or bleeding on your skin, see a dermatologist. Skin cancer is very treatable when caught early.

Nature’s Healer: The Sun

The sun has always been seen as the source of life and healing. We must not forget the many benefits the sun bestows on us. It is nature’s healer.

Sunlight

Throughout history there has been no better and more common symbol of happiness and well being than the sun. The ancient Egyptians, the Aztecs, Romans and Greeks all worshipped the sun and thought of it as the source of life and health. Regardless of the historical time that comes to mind, you will find people cheered and uplifted by the life-giving rays of the sun.

Whether it was in the form of the god Helios or establishing Sun-day as the first day of the week, the sun always has played an important role in people’s lives.

The great Greek physician Hippocrates wrote extensively about the sun’s healing powers. Herodotus, the father of Heliotherapy, made frequent statements about the healing properties of the sun in his medical practice. In our own time, we see a reflection of these ancient sentiments in songs, poems and movies. And who of us could deny the feeling we have when the sun breaks through the darkened clouds: our mood lifts; our eyes turn upward; our energy and zest for life returns.

Although there have been many serious medical warnings about overexposure to the sun in recent years, we must not neglect the positive role sunlight plays in our mental and physical health. There is good news coming from scientific research telling us why we look and feel better from the sun.

The Blues

Sunlight is an important part of our daily lives. Ever notice how much time is spent at the office worrying about who gets the office with the window. And what about all that energy you feel when spring and summer come around. Everyone seems to be outdoors, planning hikes, barbecues and pool parties. You name it and it’s happening.

Tom Wehr, M.D., a research psychiatrist at the National Institutes of Health, is an expert in mood disorders and feels that our elevation in mood during the spring and summer can be directly linked to the amount of sunlight we are exposed to. “Researchers have found the exposure to natural light increases the production of serotonin, a chemical that stimulates the brain’s pleasure center, thereby perking up your mood while warding off anxiety and depression.”

In contrast, look at what happens to people in the long winter months, especially those living in the Northeast and Northwest. Over 11 million people suffer from what is called Seasonal Affective Disorder or SAD, and another 25 million suffer from a milder form of “winter blues.”

The symptoms of SAD and the “winter blues” can include fatigue, craving carbohydrates, irritability, sleeping more and a change of personality from your summer self to your winter self. It’s not exactly known what causes SAD, but according to health writer Francis FitzGerald, “SAD occurs year after year during a specific season – usually the winter – and vanishes when spring ushers in longer days and more sunshine.”

Medical Researchers think that our depressed moods during the winter may be the result of a chemical imbalance between serotonin and melatonin. With too little sunlight, melatonin makes us drowsy, and disrupts our internal clock.

Our Bodies

Besides just making us feel better and more energetic, exposure to sunlight plays an important role in helping us create vitamin D in our bodies. What makes this so important? Vitamin D has been shown to help prevent and treat serious medical conditions, including: breast cancer, osteoporosis, prostate cancer, psoriasis, acne, etc.

Though many people aren’t aware of it, most of our physiological requirements for vitamin D are provided for by casual exposure to sunlight. It is easy to see how important sunlight is for our physical and mental health.

Breast Cancer

Over 180,000 women will be diagnosed with breast cancer this year. It is a major concern for women of all ages. But there is hope. According to Judy Gaillard and Donald Smith of Sun Wellness magazine, a study by researcher Ester M. John at the Northern California Cancer Center, entitled “Vitamin D and Breast Cancer Risk…” casual exposure to sunlight, along with other factors, can help reduce the risk of breast cancer.

The scientists concluded “high exposure to sunlight was associated with a 25 percent to 65 percent reduction in breast cancer risk among women whose longest residence was in a state of high solar radiation.” A 25 percent reduction in the number of breast cancer cases would mean approximately 44,000 women would not have to suffer the trauma of this disease. Since vitamin D and sunlight exposure are life-style behaviors, this is good news for women wishing to reduce their risk of breast cancer.

Osteoporosis

Sometimes called “the silent disease,” osteoporosis is the loss of bone mass due to the malabsorption of calcium into the bone. Bone fragility results in increased risk of bone fracture in many parts of the body, including the hips, spinal vertebrae, and ribs. According to James F. Balch, M.D., author of Prescription for Nutritional Healing, fully “half of all women between the ages 45 and 75 show signs of osteoporosis.” Although osteoporosis is mostly an issue for post-menopausal women, both sexes and all age groups suffer from this disease.

“If vitamin D is absent, calcium, which is vital for normal bone growth and development, will not be absorbed from the intestinal tract and the bones become deformed,” says Zane Kime, M.D., M.S. in his book Sunlight. One of the best ways to get adequate vitamin D is moderate exposure to the sun. The World Health Organization Task-Force for Osteoporosis recently recommended sunlight as a part of the treatment and management of this disease.

Prostate Cancer

Prostate cancer is the second most common cause of death from cancer in men over age 75. In a recent study by Hanchette and Schwartz of the University of North Carolina and published in the journal Cancer, the researchers a 20 to 40 percent lower incidence of prostate cancer among men in southern climates. Because of findings like this some researcher are suggesting that vitamin D may be an effective preventive agent against prostate cancer. The importance of sunlight cannot be underestimated in maintaining prostate health. If the incidence of prostate cancer is reduced by 20 percent nearly 37,000 men would not suffer the anguish of this disease.

Athletic Achievement

Most of us believe that sunlight gives us extra pep and energy. During the summer months, we tend to sleep less, play more and just have more get up and go. To back up this idea scientifically, Bylle Dopps and Scott Hoover of Sun Wellness magazine looked at research from the Sports Medicine Department of the German National Olympic Team Training Center. The results of their research showed that routine exposure to the sun optimized performance capabilities and reduced the incidence and recovery time of athletes from minor injuries.

If simple sunlight can help world class athletes recover from the stresses of training and competition, it seems reasonable to conclude that we can all benefit from the stress busting affects of sunlight.

Conclusion

Recent scientific studies have demonstrated what humans have suspected all along: natural sunlight promotes feelings of well-being, improves immune function, promotes natural healing and optimizes athletic performance. Don’t neglect these positive benefits of sunlight. Include moderate exposure to the sun in your overall health regimen.

More Sun Exposure may be Good for Some People

A new study by scientists at the U.S. Department of Energy’s Brookhaven National Laboratory and colleagues in Norway suggests that the benefits of moderately increased exposure to sunlight – namely the production of vitamin D, which protects against the lethal effects of many forms of cancer and other diseases – may outweigh the risk of developing skin cancer in populations deficient in vitamin D.

“We know that solar radiation is the leading cause of skin cancer,” said communicating author Richard Setlow, a Senior Biophysicist Emeritus at Brookhaven and a well-known expert on the link between solar radiation and skin cancer. Setlow’s group was the first to establish that ultraviolet A (UVA) radiation and visible light are the primary causes of malignant melanoma, the deadliest form of skin cancer. He and his colleagues emphasize that people need to protect themselves from the harmful effects of sun exposure.

But solar radiation is also a major, if not the main, source of vitamin D in humans. In the presence of sunlight, the body converts certain precursor chemicals to active vitamin D.

“Since vitamin D has been shown to play a protective role in a number of internal cancers and possibly a range of other diseases, it is important to study the relative risks to determine whether advice to avoid sun exposure may be causing more harm than good in some populations.” The concern, he says, is particularly great in populations from northern latitudes, such as Scandinavia, where sun exposure is extremely limited.

In the current study, Setlow and his colleagues used a model incorporating information on solar radiation intensity and a vertical cylinder shape to represent the human body’s skin surface to calculate the relative production of vitamin D via sunlight as a function of latitude, or distance from the equator. The cylindrical model more realistically represents human body sun exposure than flat surface exposure measurements used in previous models. The scientists also examined the incidence of and survival rates for various forms of cancer by latitude.

According to the calculations, people residing in Australia (just below the equator) produce 3.4 times more vitamin D as a result of sun exposure than people in the United Kingdom, and 4.8 times more than people in Scandinavia.

“There is a clear north-south gradient in vitamin D production,” Setlow says, “with people in the northern latitudes producing significantly less than people nearer the equator.”

In populations with similar skin types, there is also a clear increase in the incidence of all forms of skin cancer from north to south. “This gradient in skin cancer rates indicates that there is a true north-south gradient in real sun exposure,” Setlow says.

The scientists also found that the incidence rates of major internal cancers such as colon cancer, lung cancer, and cancers of the breast and prostate also increased from north to south. However, when the scientists examined the survival rates for these cancers, they found that people from the southern latitudes were significantly less likely to die from these internal cancers than people in the north.

“In previous work, we have shown that survival rates for these cancers improve when the diagnosis coincides with the season of maximum sun exposure, indicating a positive role for sun-induced vitamin D in prognosis – or at least that a good vitamin-D status is advantageous when combined with standard cancer therapies,” Setlow says. “The current data provide a further indication of the beneficial role of sun-induced vitamin D for cancer prognosis.”

So, how can people get the benefits of vitamin D without running the risk of deadly skin cancer”

“As far as skin cancer goes, we need to be most worried about melanoma, a serious disease with significant mortality,” Setlow says.

Melanoma is triggered by UVA (the long UV wavelengths) and visible light. Vitamin-D production in the body, on the other hand, is triggered by UVB (the short UV wavelengths at the earth’s surface). “So perhaps we should redesign sunscreens so they don’t screen out as much UVB while still protecting us from the melanoma-inducing UVA and visible light,” Setlow says.

Increased UVB exposure may result in an increase in non-melanoma skin cancers. But these are relatively easy to cure and have very low mortality rates compared with the internal cancers vitamin D appears to protect against, Setlow adds.

Another option would be to increase vitamin D consumption while continuing to wear sunscreen. Vitamin D is easily accessible in many foods and liquids, such as cod liver oil and milk, and in dietary supplements.