It was a conversation with my doctor, years ago, that first peaked my curiously about the risk vs. the reward of sun exposure. As I confided in him about the onset of depressive symptoms he asked if they got worse in the wintertime? I practically rolled my eyes at him. I had heard about Seasonal Affective Disorder in my psychology classes, and was certain my symptoms warranted a more serious diagnosis than something called SAD! Still, I agreed that maybe it was possible that I had become more depressed nearing the latter part of winter. But if this was true, I thought, what could possibly be the explanation? Was it because of the shorter, darker days? More time spent inside because of the extreme cold we experience in Canada? What did all these variables have in common?
First, A Few Facts
Ultraviolet Radiation (UVR) is part of the light spectrum that makes it from our favourite star in the sky to the rock we call home. UVR is comprised of 3 main types of UV rays; UVA, UVB, and UVC.
The ozone absorbs UVC rays before they can hit the earth but UVA and UVB rays make it to the party. UVA (long wave) rays account for most of the natural UVR we are exposed to (95%). While over exposure has been known to cause cosmetic (think wrinkles and skin aging) damage, it’s only recently that researchers discovered UVA rays damage the epidermis (outer most skin layer) where skin cancer occurs. UVA rays are also responsible for the sought after summer tan.
UVB (short wave but not as short as UVC) rays are the ones that are responsible for the sunburn I got during track and field day in the seventh grade. These bad boys don’t penetrate as deeply into the skin but can do a fine job frying the epidermis (sunburns, redness) and are responsible for most skin cancers that develop from sun over exposure.
Now I know all that sounds awful; in fact I spent years hiding my pale, freckled skin from the sun. The promise of accelerated aging and skin cancer was enough to have me slathering on SPF 50 and donning ginormous sunglasses all summer long. Even in the winter months I made sure my foundation had an SPF because UVR doesn’t take a winter vacation.
Vitamin D is the only essential vitamins that can be attained independent of eating. Vitamin D can be made during a photosynthetic reaction that occurs when our skin gets exposed to UVB rays. The amount our bodies create depends on multiple factors such as clothing, skin pigment, time and location of exposure, and even amount of excess body fat.
The main purpose of vitamin D is to maintain our calcium and phosphorus levels that have long been known to support healthy metabolic function and bone mineralization. Recently however, the significance of a lack of vitamin D has been grabbing researchers attention.
Insufficient vitamin D has been proposed to play a role in a variety of diseases and cancers that have proven to have a much higher rate of disability and morbidity than skin cancer. A lack of vitamin D has been associated with depression, anxiety, cardiovascular disease, arthritis, Hodgkin lymphoma, MS, osteoporosis, diabetes, as wells as breast, ovarian, colon, pancreatic, prostate, and other cancers. It is hypothesized that close to a billion individuals worldwide have either insufficient or deficient vitamin d levels. That is a lot of potential illness that may be preventable with sensible sun exposure.
A Short History of Healing with the Sun
Using the sun for healing purposes is hardly a new idea. There is evidence of Heliotherapy (Helio coming from the Greek god of the sun Helios) being used to treat disease and promote wellbeing in the ancient times of Greece, Egypt and Rome. Nobel prize winner (1903) Niels Ryberg Finsen successfully treated cases of lupus, small pox scarring and other skin ailments with sun exposure.
In the late 1800s and early 1900s tuberculosis (TB) was a major cause of early death. Finsen hypothesized that Heliotherapy could be used as a treatment for the bacterial disease. While his treatment showed promise, his northern location in Denmark did not seem to supply a sufficient amount of the sunrays necessary to produce the antimicrobial peptide called cathelicidin that is now thought to be the key component in curing TB. Fortunately, others followed in Finsen’s footsteps, opening up heliotherapy hospitals in the Swiss Alps, south of France, and America that were successful at curing 1000's of patients.
It is important to note that patients were not simply rolled out into the midday sun on arrival to the hospital. Patients were slowly acclimatized to the air for a few days especially if they were new to the higher altitude in which most of these hospitals were situated. Sun exposure was then administered slowly, increasing the amount of skin exposed and length of exposure daily.
Unfortunately, due to the advent of antibiotics and discovery of the harmful effects of UVR over exposure, these hospitals began to shutdown and people began to shun the sun. Antibiotics seemed like a miracle cure, as recovery was much quicker than with sun exposure. But with the influx of antibiotic resistance and superbugs I can’t help but wonder if we would be better off if antibiotics were left as a last resort and these Heliotherapy hospitals were given time to further perfect their treatment plans.
Vitamin D Supplementation
Concerns stemming from over exposure to UVA and UVB rays are certainly warranted. It’s no surprise that many look for alternative sources of vitamin D. Since we achieve sufficient levels of other essential vitamins from the food we eat, oral consumption of vitamin D is an attractive alternative. Certain foods do contain vitamin D (eggs, fatty fish, beef liver), however they cannot provide the levels necessary for optimal health.
With our technology dependent societies bringing us indoors for the majority of our day, it is tempting to use technology to solve our vitamin D deficiency. While vitamin D deficiency is associated with a wide range of mental and physical diseases, its supplementation has not proven to be the reliable cure-all you might expect. Research is now pointing to sun exposure induced pathways independent of vitamin D that may play a role in disease prevention and reduced cancer risk.
Risk vs Reward
So what are we to do? Do we shun the sun, denying the copious amount of vitamin D receptors that exist all over our bodies due to the risk of melanoma?
When we look at DALYs (disability-adjusted life years), excessive UVR exposure only accounts for 0.1% of the total global burden of disease. DALYs measure the decrease in life expectancy due to illness, disability and early death. The DALYs for the diseases that insufficient sun exposure is linked to are much higher. For example, 3.3 billion DALYs result from very low levels of UVR sun exposure. Therefore, despite their higher prevalence, diseases caused by UVR exposure have a relatively low disease burden, compared to diseases that UVR exposure can help heal or prevent.
Finding the Balance
It is clear that excessive sun exposure causes damage but it is equally evident that our bodies are designed to catch rays from the sun for optimal health. How do we strike a balance?
There are 3 main variables that combine to determine our personal UVR dose required to synthesize optimal vitamin d level.
1. Skin Colour (Lighter skin pigments require less exposure than darker shades.)
2. Amount of Skin Exposed
3. Ambient UVR (a function of latitude, altitude, atmospheric ozone levels, pollution, and time of year)
The 25(OH)D test is the best way to determine if you are getting enough D in your life. 25(OH)D is a simple blood test you can request at the doctors or you can order a home test and send your sample to a lab to be analyzed. Research suggests that keeping your serum 25(OH)D level in the optimal range can reduce cancer risk by as much as 30 to 50 percent! Optimal levels are not universally agreed upon but the following gives you an idea of where you should be aiming.
Serum 25(OH)D levels
<20 deficient vitamin D
<30 insufficient vitamin D
40 - 60 optimal vitamin D (some indicate >75)
Frequent testing is not exactly a convenient way to track your levels. Fortunately there is a free app that you can download on your phone to help keep track. Just plug in your location, skin colour and overcast conditions into the Dminder app and it will give you an estimate of your current vitamin D levels! Every time you are out enjoying the sunshine you can set Dminder to keep track your exposure levels. It will even signal to you when you are likely to start burning so that you can seek shade and avoid damage!
Sensible Sun Exposure
There are some basic rules you should be following when it comes to sun exposure.
Start Slow. Start working on your base tan as early in spring as you comfortably can. Use the dminder app to make sure you’re not getting too many rays too soon.
Seek Shade. If you’re spending longer in the sun then your skin is comfortable with - find ways to block the rays. Bring an umbrella to the beach. Wear a wide brimmed hat. Wear light layers. I know a loose, light coloured long sleeve top might sound like it will cause you to overheat in the sun, but the opposite is actually true. By keeping the rays from getting direct contact with your skin, you will be able to stay outside longer and prevent skin damage.
Avoid peak hours. Stay in the shade for the hours around solar noon, when UVR rays are at their peak. Between 10am and 4pm is where you’ll find the strongest rays. Keep an eye on the UV Index. When the UV index is at 3 or above start covering up, whether it’s with clothing, an umbrella, sunscreen or the natural oils listed below. When the UV Index reaches 8 or above you should starting heading for the shade or use extreme caution, as uncovered skin can be damaged in a matter of minutes.
If you are very fair skinned or need to spend more than the recommend time under the sun (especially if within peak UVR hours) you are going to want to think about utilizing a sunscreen to prevent burns and sun damage.
SPF stands for sun protection factor and is attached to a number of commercial products. The higher the number the longer you can stay out in the sun without burning. If you can’t find a SPF higher than 50 on the shelves it is because it was not found to be of any greater protection benefit and users often spend too long in the sun without reapplying. For years, UVB were the rays of sunshine that everyone worried about being exposed to. This is the type that causes sunburns and is responsible for the majority of skin cancers. However UVA, which contains the aging rays, have also been shown to cause cancer. In fact, in North America, the left arm is most likely to develop cancerous skin cells because car windows block UVB rays while UVA rays are free to blast the drivers arm during the commute.
While wearing a wide brim hat and loose clothing that covers your skin is ideal, sometimes a sunscreen is required. The problem is that most commercial sunscreens are riddled with ingredients that we don’t exactly want baked into our skin.
In addition to looking out for the usual suspects ( i.e. parabins, mineral oils, PEGs, fragrance), Retinyl palmitate is a form of retinol vitamin A that is added to lotion to help speed up skin cell turnover and promote younger looking skin. This sounds like a great addition until you find out that even low doses of vitamin A can turn skin cells cancerous when exposed to UVR rays! Not exactly the ingredient you want in a sunscreen that is marketed to protect you from the sun!
Problems with Traditional Sunscreens
If the idea of slathering on mystery chemicals and having them bake into your skin is not enough to have you think twice about what sunscreen you apply, maybe the following facts will help to convince you.
1. Hiding the signs. Sunscreens disable our skins natural warning system, skin redness. Your choice of sunscreen could be doing a great job of blocking the reddening UVB rays, while still allowing the UVA rays to wreak havoc, and you are none the wiser because your skin isn’t reddening as nature intended.
2. No evidence of effectiveness. The sad truth is there is very little research that sunscreen alone helps prevent cancer. The International Agency for Research on Cancer stats that “sunscreens should not be the first choice for skin cancer prevention and should not be used as the sole agent for protection against the sun.” Even the FDA is aware that there is a lack of evidence demonstrating the effectiveness of traditional sunscreens.
3. Poisoning our beaches. It is not just our bodies that are harmed by sunscreen use. After we cover ourselves from head to toe with sunscreen, what do you think happens to it once it gets washed away in our lakes, rivers and oceans? All those chemicals wash off the beach goers and begin to pollute the water. In fact, this has been a serious cause of poisoning of the coral reef. Hawaii recently became the first US state to ban sunscreens with the ingredients oxybenzone or octinoxate because of the damage they are doing to the environment.
If you still choose to use traditional sunscreens make sure to use the following advice.
1. Make sure you are applying enough. Use a minimum of one ounce to completely cover your body.
2. Reapply frequently. Don’t fall for the waterproof claim on the label. No sunscreen is waterproof although some maintain greater water resistance than others. Always reapply if your spending time in the water, sweating or in a situation where it could have rubbed off.
3. Make sure your sunscreen is broad spectrum and protects you from both UVB and UVA rays. For years manufacturers of sunscreen only cared about protection from the skin burning UVB rays. Broad spectrum on the label ensures protection from both rays.
4. Stay away from sprays due to inconsistent application and inhalation risk. Store out of the sun (especially when at the beach!) and always check the expiration date. Regulation states that if a sunscreen remains stable for more than three years it doesn’t need to display an expiration date. Therefore, if there is no date on the product, trash it after the three-year mark.
Click here for a list of EWG (environmental working group) approved sunscreens.
Alternatives to Traditional Sunscreens
Fear not, if spending an extended amount of time in the sun is unavoidable and you’re starting to distrust traditional sunscreens, there are thankfully some alternatives that you use to help you stay sun kissed instead of sun scorched.
Zinc oxide sits on top of the skin and provides full spectrum UVR protection. Zinc oxide is not the most ascetically appealing option as it leaves a white film that can be seen on skin. However, be wary of zinc products that claim to not leave the white tint. These options likely have ground up the zinc into nano particles that are now small enough to be absorbed into the skin and cause a real problem. Zinc Oxide has a protection factor comparable to about SPF 2-20 depending on how much is applied.
A popular option for the chemical conscious crowd is the use of natural oils as sun protection. These oils have the benefit of actually nourishing our skin while providing you protection against UVRs.
Here is a list of natural oils and their comparable SPFs
SPF 4 to 6: Almond Oil, Coconut Oil and Shea Butter
SPF 25 to 50: Red Raspberry Seed Oil
SPF 35 to 40: Carrot Seed Oil
My personal sun care solution is to mix a zinc product with a natural oil in order to diminish the white cast while still protecting my skin.
You may have noticed a common sun safe suggestion missing from the above discussion. Sunglasses have been one of my favourite accessories for years but recently I’ve been seeing them in a new light.
Hypersensitivity to Light & Circadian Rhythms
Our eyes contain photosensitive cells that directly communicate to the hypothalamus, which controls our circadian clock. Keeping our circadian clock ticking on track is vital for healthy sleep patterns and hormone regulation. Stimulation of these eye cells comes from blue light produced by the sun. Deprivation of this sunlight spectrum can have psychological and physiological consequences, which includes a greater risk of disease. Sunglasses block this vital blue light and desensitize the photoreceptors in the eyes, causing a hypersensitivity to light. Your ability to adjust to sudden changes in lighting conditions is greatly disturbed and you end up needing to where sunglasses more and more. When you forget your sunglasses at home your greater sensitivity will cause excessive squinting, which in turn can cause unnecessary wrinkles and irritation of the eyes.
A great way to resynchronize your circadian rhythms and reduce your sensitivity to light is an exercise shared by optometrist Jacob Liberman in his book “Take Off Your Glasses and See” called sunning. The best time to perform sunning is in the early morning, right after sunrise or about an hour before sunset when the sun is at its lowest. Make sure you are breathing deeply and your eyes are closed softly. Stand facing the sun with your eyes closed and slowly move your head side to side a few times. Then, with your eyes still closed, slowly nod your head up and down. If you are experiencing any after images make sure to not immediately open your eyes after sunning. Palm one eye at a time until you feel comfortable enough to open both eyes.
Liberman also states that there is nothing wrong with wearing sunglasses on days where the sun is especially bright. He simply cautions that you shouldn't wear them every time you are exposed to the sun. The less you wear your sunglasses, the less you will miss them. It won’t take very long until your eyes are no longer straining to see in bright light and can adjust appropriately to changing conditions.
So, what about you? Are you a sun shunner? A sun soaker? A combination of the two? Let me know in the comments below how you are handling your sun care this summer!
Thanks for reading!