Tag Archives: SPF

sunscreen, sunburn

When Your Sunscreen Burns You

When Your Sunscreen Burns YouScreen Shot 2017-05-31 at 12.32.18 PM

Screen Shot 2017-05-31 at 12.32.10 PM

Solar Simulator Estimated SPF of Sunscreen with the above actives

Editor’s Note: Since this post’s original publication, Canada has also been reeling from several incidences of infants receiving severe 2nd degree burns while using sunscreens specifically marketed for children. In looking at one of the product reported, Banana Boat Kids Free SPF 50+, it fortunately does not have some of the red flags that I have seen in other children spray sunscreens like alcohol and oxybenzone.  My quick assessment of the product leads me to suspect that it’s unlikely to be a true SPF 50+ with ingredients of 3% avobenzone, 6% octocrylene and 10% homosalate.  In looking at the solar simulator, a helpful on-line tool for estimating SPF and the UVA protection factor, this ingredient load would give an SPF of 15-17.  I would also consider whether the avobenzone was fully stabilized from photo-degrading (i.e. breaking down in the sun) by the octocrylene.  Finally, spray sunscreens are always problematic because you can just never be sure that you are applying adequate amounts evenly.  I understand they are convenient for children (I have a wriggly toddler so I REALLY understand) but stay tuned for some tips for applying sunscreen and providing the best protection against the sun for young children in our next blog post.

In today’s digital age, it’s common place for alarming stories to bubble up and go viral, typically with the pictures to match.  Pictures of bad sun burns can sometimes make for fun Buzzfeed columns but when children are involved and their burns are significant, the stories are heartbreaking.

The news cycles in Australia and New Zealand are replete right now with the story of a brand of sunscreen manufactured for their skin cancer council called Peppa the Pig.  This was a brand of sunscreen especially marketed towards kids so the several pictures of young children with 2nd degree burns were shocking to everyone.   Many questioned- how is this possible?

We source our zinc oxide from Australia and in our minds, we always imagined it to be the land of sunscreen.  You can imagine the need for it.  It’s one of the few places in the world with a predominantly fair population with never ending and intense sun.  I was surprised then when I was corresponding with a beauty e-commerce owner in Australia about what she felt was the complete lack of good options.  She said they also faced the same issue with consumer confusion.  Many were starting to get the message that they needed to wear sunscreen every single day but most stumbled in trying to decipher what to use.  So many people were still getting caught in the trap of relying on the front of the box where their only real cue for information remains the SPF.  As we’ve stated many times (here and here), SPF can be a misleading piece of information, especially if it’s the only piece of information you are looking at.  The real source of information remains the ingredient list, however, I concede that is a daunting task to wade through complex chemical names and percentages (if available!) even for professionals.  We continue to use a tool called the Sunscreen Simulator- it’s an online tool created by a provider of sunscreen filters that allows you to graphically see what your protection looks like.  It’s not perfect but it’s one of the few tools we have.

In taking a cursory look at the family of Peppa the Pig products, they do contain some ingredients with questionable photo allergy data.  Encazamene is a filter that we do not have here in North America. There are studies that show it has potential issues with photo-allergy.  We also would never use it in our formulations as it’s a small particle sized filter that can enter the body.  The products also contained Avobenzone, which is ubiquitous in the market.  It also has a small risk of photo-allergy (about 1% in the general population) but we also would never use it since it can enter the body.  Moreover, research is mounting about its potential as a serious endocrine disruptor with a similar profile as oxybenzone. Click here to read more about that.

The Peppa the Pig situation prompted the very understandable consumer reaction of calling for more regulation.  This incident does represent a failure on the part of regulatory bodies. However, it’s not an issue of lack of regulation but one of focusing on the wrong pieces of information.  In an ideal world, we would have a global standard for sunscreen regulation.  We wouldn’t have the current situation where some countries had better access to better sunscreen filters than others.  We would settle on a robust standard for measuring the UVA protection of a sunscreen and would represent that in a meaningful and clear way on the label for sunscreens.  We would find a better test for measuring SPF that does not allow manufacturers to ‘game’ the test and falsely inflate their SPF .  We would review every single filter, both old and new, from an integrated medical perspective.  In short, we would look at its effectiveness but also at its potential impact on our health, including hormonal health and the environment.  We’d use the precautionary principle to say that if an ingredient had significant concerns associated with it- that would be enough to call for a suspension of use.  Especially, as there are many ingredients that do not have controversy with them and are effective.

The secondary cost of these incidences remains that consumer faith gets shaken in products that are meant to protect.  The confusion leads many to just abandon the use of sunscreen altogether.  It’s an unfortunate reaction that would only lead to more potential for damage.  Education and advocacy remain our only tools and engaging through our professional communities our means for spreading the word.

We’d love to hear your take on this so please leave us your thoughts in the comment section.

All the best,

Sara

Melanomoa, Skin Cancer, Melanoma awareness

Surviving Melanoma: The New Face of Skin Cancer (and it’s younger than you think)

Melanomoa, Skin Cancer, Melanoma awareness

Surviving Melanoma- The New Face of Skin Cancer

When we learned how fast the rates of melanoma were increasing in teenagers and people aged 25-35, we knew we had to do our best to get the word out especially as May is Melanoma Awareness Month. Why is skin cancer the number 1 cancer killer for young women ages 25-35? What demographic shift has happened to make this a huge concern for Millennials?

It’s obviously a confluence of lifestyle factors that are making this a serious trend.  My theory (and it’s only a theory) is that the sunscreens from the 90’s that we grew up with might have role to play.  I remember how great sunscreen was as a kid- you could do a quick coat and then with the odd re-apply be good to stay out all day long and not burn.  We know those sunscreens had real stability issues and were UVB biased- it was just the state of the science back then. It would stand to reason that we are now paying for this childhood exposure some twenty years later. There are better sunscreens available now so hopefully we will not see this trend continue for our children but of course that depends on choosing a good sunscreen, enacting good compliance and observing other sun safety measures.

Anyways, enough from me.  When I heard Julie’s story, I knew we had to share.  It absolutely obliterates the myth that melanoma equates to removing a bad mole in your doctor’s office.  It’s a life changer and it can be heart wrenching.  Here’s her story in her own words.

Julie, 35 year old Teacher

What were you diagnosed with and when?
I was diagnosed with Stage 1 Melanoma Skin Cancer of the left Ear Helix, in March 2014. I first had noticed a bump on my ear on January 1st celebrating New Year’s Eve in Huatulco Mexico with family while putting on sunscreen. This would be the start of a world-wind of a year physically and emotionally.
After being diagnosed, and reeling from the devastating news, they informed me that not only did they have to remove a significant part of my ear, but that it was medically suggested to remove my sentinel lymph node in my neck since there was a small possibility that the cancer might of spread due to the melanoma’s initial size of 1mm as well as they found that some of the cells shown that they had metastasized. This was to be very invasive with possible worst case scenario side effects such as nerve damage to facial, tongue, shoulder muscles or diaphragm.
Two days before my operation, my surgeon informed me that they would scale back the decision to remove my sentinel lymph node since the chances of it spreading were so minimal as compared to the invasiveness and the fact that if it had spread that the removal didn’t change the prognosis.
It’s a common perception that having skin cancer treated is normally the equivalent to having a mole removed at your doctor’s office, can you share how your treatment proceeded?
This was, as for many other patient’s going through this type of diagnosis, certainly not a routine or non invasive procedure. Due to the location of the melanoma, in my case to be on the helix part of my ear, I had to undergo a 1 hour surgery under anaesthesia to remove a pie shape piece of my ear, inserting over 50 stitches to be able to resew both sides back together. Two weeks later they removed the bandage I had to wear the entire time, as well as most of the stitches, to which I was finally able to go back to work. I could not sleep on the left side  for 3 months after the operation since it was still very sensitive to touch and pressure. This proved to be very difficult due to the fact that I was a toss and turn type of sleeper, therefore, did not sleep to my full potential for those 3 months.
What is your current status with your treatment?
From the day of my operation on April 16,2014, I have been Melanoma free. I have routine check-ups every 3 months to monitor the healing process of the ear as well as to monitor any symptoms of possible spreading to my sentinel lymph nodes, of which due to the 1mm size of the Melanoma Cancer there was a 2% chance that it had spread. I will be officially in remission after 5 years of being monitored.
What was your initial reaction when you were first diagnosed?
I was in a state of  shock. Nothing can really prepare you for that type of news. The feeling of regret, helplessness and sadness all rolled into one, which was so foreign to me. I was and slowly getting back to being the person , dare I say, that always has a tremendous sense of confidence and  instinctive ” joie de vivre”.
Has this changed how you feel about your health in general? What’s it’s impact been on you: physically and emotionally?
I live my life with an even deeper appreciation of my health in general .Since this has happened I unfortunately have been overly in tuned with any changes with my body, and this sometimes not for the best. Every headache, every ear ache, or any ailment my thoughts automatically are that the cancer had or is spreading , to my brain, to my lymph nodes, which is probably a very unlikely occurrence, but nonetheless a worry I have ever since the diagnosis.
Physically, I now have a significantly smaller ear, which to the naked eye or to someone that doesn’t know me wouldn’t of noticed, but I certainly do. However, this was a physical change that has no subsequent consequences to my daily functions. It is primarily an aesthetic change, and in my case, not directly on my face, and can be hidden by my hair when I wear it down.  I am a physical education teacher, as well as an active person, therefore, I do wear my hair up often which does expose my ears, and I am at the point that it does not bother me anymore.
 It has been an adjustment in some areas :  ie. talking on the phone with that ear, sleeping on that ear, sunglasses or glasses affecting the ear, but they seem to be subsiding with time and who knows, will probably be a non issue in the near future, and if not, like I had explained such a small sacrifice compared to so many.
I understand that self-esteem is directly linked to our physical appearance, but thankfully my confidence in myself does not center on that aspect. I focus on the fact that many more people have suffered greater loss or more severe physical ailments, due to cancers, diseases or even accidents. I am just so grateful.
Has this changed how you feel towards sun exposure and the outdoors?
Since the day I noticed the abnormal mole , and to this day, I am no longer a fan of the sun. Knowing more in depth what I know now, and realizing that my cancer was caused by a combination of pre-disposed genes, but more importantly my negligence to the strength and danger of the sun, I definitely try my best to avoid being in the sun, directly and to that matter without the best skincare products offered to protect it.
What has been the hardest part from your diagnosis through to your treatment?
The hardest part is the unknown. The fact that there is, and will be for 5 years, still a small chance that it had spread to my lymph nodes and that only time will tell, has been very difficult and caused anxiety, which is very foreign to me. However, I  focus on the positives and the fact that the overwhelming chances are that it will not re-occur, and that I have an important role by being diligent with protecting my skin.
How worried are you about re-occurrence? 
I would lie if I said I had no worries of re-occurrence. At the beginning, it was a daily thought. Once first diagnosed, it was many of those thoughts throughout a day. However, slowly but surely, it is fewer than once a day. There are events, movies, words, and even physical pain or ailments that can trigger a mini emotional roller-coster, but I have always found a way to turn into a positive and appreciate even more the life I lead.
 How has your perspective changed in relation to the sun?  Has it changed your behaviour?
Yes, it has drastically changed. I used to be of the thought that since I didn’t burn from sun exposure, I didn’t need to wear sunscreen. And how regretful I am now for this misconception and ignorance on my part.  I now  apply sunscreen daily on my face ,  as well as try my best to wear a hat to protect my face from any unwanted direct sun rays. If I am exposing the rest of my skin, I ensure that I reapply often and stay out of the direct sun as much as possible.
cyberderm, the sunscreen company, sunscreen, SPF, best sunscreen

Why the Term “Broad-Spectrum” on Your Sunscreen Label May still be False.

The most important objective of photoprotection must be to prevent rising rates for skin cancer and reduce health care expenditures for a largely preventable disease. It is now accepted that UV radiation is the main cause of photocarcinogenesis, photoaging and immune suppression. The risk of sunburn from UVB exposure has long been implicated as a major hazard to human skin. Recent studies support a more prominent role for UVA over UVB in genetic damage to the keratinocytes in the basal layer of the epidermis where most cancers occur. This basal layer shows more UVA than UVB fingerprint mutations, suggesting a primary role for UVA in human skin carcinogenesis. A contemporary view is that UVB causes direct DNA damage, whereas UVA results in direct DNA damage and indirect effects from ROS, photoimmunosuppression, and disruption of repair mechanisms. UVB initiates and modulates these harmful effects whereas UVA is responsible for widespread effects and completing the damage cycle. Photoprotection with traditional UVB biased sunscreens with little or no UVA protection must now be abandoned and a new clinical strategy adopted.

Rising cancer rates show that the current approach has failed and critical analysis argues that ineffective UVB biased sunscreens are an important contributory factor. A minority of the products available in Canada or the USA provide adequate protection against the deeper penetrating UVA-I (340-400nm). In North America > 80% of products claim or imply UVA absorption by labels such as “broad-spectrum or extra UVA protection” despite containing no effective UVA filters, particularly in the UVA-1 band. The Environmental Working Group (EWG) assessed over 1800 sunscreens and found that 90% had little or no UVA-I protection, despite a broad-spectrum label claim. Consumers are lured into assuming that they are being protected from the entire solar UV spectrum (290-400nm), and are distracted by high SPF numbers into mistakenly believing that their sunscreen is reducing all the risks of sun damage. Sunscreens that absorb mainly UVB denoted by the SPF number, reduce the risk of sunburn but may be detrimental by allowing you to stay out longer. You do not burn but you actually increase your risks from UVA injury – immune suppression, premature photoaging, and skin cancer. A few N. American sunscreens offer some UVA filtering but most fail to provide the minimum UVA protection required in Europe.

Health Canada and the FDA changed their regulations in 2011 to ensure that a broad spectrum claim was an accurate one. For decades, the SPF on a product’s label was the only measurement available to consumers to help make a decision about a sunscreen’s protective capabilities. SPF values indicate UVB and UVA-2 protection from 290 to 340 nm. There was an urgent need to enable the consumer to assess the UVA-1 protection afforded by a sunscreen like Europe and most other countries outside N. America. Both countries adopted the rule of the Critical Wavelength (CW) test. The CW can be assessed by a variety of in-vitro tests that plots an absorption curve and assesses the wavelength on the y-axis where 90% of the area of the curve falls under. If 90% of the curve falls on or after the 370 nm mark (the portion of UV light that is considered the longest wavelengths of UVA) then the sunscreen can be labeled ‘broad-spectrum’ under the new law. See Figure 1 for an example.

Screen shot 2015-04-02 at 9.49.17 AM

The Critical Wavelength Test does not by itself provide an accurate assessment of whether a sunscreen is broad spectrum. The following are some reasons why the test can be misleading:

  • The test is a relative comparison of UVB vs. UVA, not a test of absolute
  • The result of the test is affected largely by the shape of the curve.

Figure 2 (absorption curves) and Figure 3 (sunscreen actives and concentrations in comparison to CW result) shows how the CW sometimes fails to accurately describe the true protection profile of a sunscreen.

Figure 2: Absorption Curves of Four Brands[1]

[1] Results from testing of actual products at an independent third party laboratory

The Absorption of UVB  (290-320 nm) through UVA (320-400 nm) of Four Different Sunscreen Formulas

The Absorption of UVB (290-320 nm) through UVA (320-400 nm) of Four Different Sunscreen Formulas

Figure 3: Sunscreen Brands with their Actives and Critical Wavelength Result[1]

Formula Curve Colour Actives Critical Wavelength Result
Every Morning Sun Whip SPF 25 Dark Blue 15% Zinc Oxide, 7.5% Encapsulated Octinoxate 362
Simply Zinc Whip Sun Whip SPF 30 Green 22% Zinc Oxide 370
Brand E SPF 45 Light Blue 9% Zinc Oxide, 7.5% Octinoxate 372
Brand C SPF 30 Light Red 1.9% Zinc Oxide, 3% Titanium Dioxide 376

[1] SPF values are as reported on product labels, Critical Wavelength results are from testing of actual products at an independent third party laboratory

In Figure 2, the Green Curve offers the highest levels of protection through the full range of UVB and delivers excellent UVA protection. It represents our Simply Zinc Sun Whip SPF 30 with 22% zinc oxide as its only active ingredient. You can see that it offers the highest protection at every wavelength and is flat confirming that it delivers “balanced” protection – virtually equal protection at every wavelength in the UV band (290-400nm).  Experts recommend that the ideal sunscreen must achieve this quality confirmed by an absorption curve that is high and flat. This product that gives the best photoprotection had a CW measured at 370 nm and barely passed the CW test. It can be labeled broad-spectrum, but based on CW would appear to be less protective than Brands E and C.

The other three curves compared to each other provide the best examples of the flawed nature of the CW test. The light pink curve, Brand C SPF 30, has the highest Critical Wavelength result of 376. It also has the lowest concentrations of actives at about 2% Zinc Oxide and 3% Titanium Dioxide. It has the lowest curve as expected, and offers the lowest amount of protection from 290 nm to 370 nm. It gets a high Critical Wavelength result because its curve is flat. Therefore, while it meets the criteria of being relatively flat it does not meet the criteria of being high. It gives uniformly poor protection at every wavelength from 290-370 nm and virtually none at 370-400 nm.

The Dark Blue (the Every Morning Sun Whip SPF 25 with 15% Zinc Oxide and 7.5% Encapsulated Octinoxate) vs. the Light Blue curve (Brand E SPF 45 with 9% Zinc Oxide and 7.5% Octinoxate) confirms that more Zinc Oxide is always a better thing. The Dark Blue curve (Every Morning Sun Whip SPF25) offers more protection at every point from 290-370 nm, despite a CW of 362 due to the shape of its curve. Its encapsulated octinoxate gives better UVB absorption than the regular octinoxate in Brand E. It fails the CW test but gives better protection than brand E that passes. The shape of the curve may erroneously negate the actual level of protection in some cases. More protection is obviously a good thing in real life. Yet it may shift the CW curve to the left and fail a sunscreen. To pass the arbitrary CW 370 nm standard, one could reduce the level of encapsulated octinoxate in Every Morning Sun Whip from 7.5% to 4% by flattening the curve and shifting the 90% crossover to the right. Less protection gets you a pass like many sunscreens that now make a label claim that is misleading or false.

The CW is used in Europe along with the SPF/UVA-PF ratio to show the consumer the actual level of UVA protection relative to the UVB level or SPF. The ratio has to exceed 1/3. This means that for a SPF 30 sunscreen UVA Protection Factor has to be > 10, for a SPF 60 product UVA-PF has to exceed 20. The CW is a second but less important metric that gives the “balance” of the broad-spectrum activity, once the first criteria is achieved, the higher the CW is above 370, the more UVA protection afforded. The CW alone is a flawed measure of UVA activity and the balance or broad-spectrum nature of the sunscreen. Professor Brian Diffey of Newcastle University who developed the test is the harshest critic of the FDA for adopting this test as the sole measure. There is expert consensus that using CW alone fails to ensure adequate UVA protection required for true broad spectrum coverage.

Dominique Moyal from L’Oreal Research & Innovation called attention to this issue in 2001. He presented photometric data from 2 sunscreens labeled “broad spectrum”, with SPF 15 and CW 370 nm. One had a UVA-PF of 2.4 and the other 10.4. The former would have a UVA index (SPF/UVA-PF ratio) of 0.16 a fail in the EU, the latter a UVA index of 0.66 showing balanced protection and pass in the EU. Both would now pass in N.America. He presented the data for 16 sunscreens with SPF values 15-60 and showed there was no linear correlation (the data scatter was wide) between CW and SPF/UVA-PF values. Furthermore, a CW ≥ 370 nm is not equivalent to a ratio UVA-PF/SPF ≥ 1/3 and a high SPF and CW > 370 nm doesn’t ensure a higher UVA protection than a lower SPF product with the same CW.

These curves are also instructive in relation to their labeled SPF. You’ll notice that within the UVB portion of the curve (from 280 nm to 320 nm), the highest curve is again our Simply Zinc Sun Whip SPF 30. Many sunscreens report an inflated SPF by manipulating the SPF test done on human volunteers. Anti-inflammatory or antioxidants that reduce the redness on skin falsely elevate the SPF result that depends on the degree of erythema or redness as read by an observer. The skin appears less red not by a true reduction in UV radiation but by masking the biologic endpoint that in real life warns you to get out of the sun.   In-vitro SPF testing does not depend on the degree of erythema and cannot be rigged, and is being refined by The ISO, hopefully to become a global standard. From the absorption curves, there is no possible way that Brand E can have an SPF 45 when it has lower absorption in the entire UVB portion than Simply Zinc Sun Whip SPF 30 with the highest UVB absorption. Brand E labeled SPF 45 also has lower absorption in UVB than Every Morning Sun Whip SPF 25. Finally, Brand C (light pink curve) labeled SPF 30 cannot possibly have a true SPF 30 and be positioned considerably lower than our sunscreens at SPF 30 and SPF 25.

Consumers are once again left without a clear way of knowing the true protective qualities of a sunscreen. Products that do not pass the Critical Wavelength test of 370 nm must label their products as only protecting against sunburn and not skin cancer or photo-aging. Those that pass make a very specific claim that they aid in preventing cancer and photoaging. That may be entirely false and we have the contradiction that sunscreens not able to make the claim provide superior protection than those that do. The consumer is actually worse off than before. The broad-spectrum claim was somewhat generic and many consumers may not have appreciated its exact significance and that it was misleading. Now we have a very specific claim of protection against cancer and photoaging, which may still be misleading or untrue in many cases.

Consumers in N.America deserve an easy way of assessing their sunscreens but they also require an accurate one. The SPF/UVA-PF combined with the CW as required in Europe would have provided both. Industry lobbyists influenced the FDA to move away from this and a similar reliable standard- The Boots/Diffey Star Rating. Using either standard would have excluded the majority of our sunscreens that did not provide adequate UVA-1 or true broad spectrum protection. The use of the limited CW test alone allowed many deficient sunscreens to pass. We advise consumers to look at the active ingredients in a sunscreen for the best assessment. Currently in North America, Zinc Oxide is the best and safest broad-spectrum filter that protects against all UV bands, but the most efficiently against UVA rays. Consumers must remember the truism that the more zinc oxide -the better your reliable and actual protection.

 Conclusions:

  • Zinc Oxide provides the most broad-spectrum protection and remains the best UV filter available in North America.
  • More Zinc Oxide means more protection. Consumers should look for the protection afforded by levels at 15% or more approaching the allowable maximum of 25%, and expect protection to decrease the lower the concentration.
  • Overall protection may be improved within the 15-25% range by adding other agents like titanium dioxide (UVB and some UVA-2 protection) or encapsulated octinoxate (UVB).  Both are large molecules that remain within the outer dead layer of skin (stratum corneum), and like zinc oxide, they avoid the risks of soluble filters that are absorbed through the skin, such as hormone disruption, reproductive problems or cancers, and rarely photocontact skin allergy or irritation.
  • The FDA and health Canada continue to deprive N. American consumers of access to the benefits of Tinosorb S™ and Tinosorb M™, two excellent broad-spectrum filters with good safety profiles according to the EWG, and widespread use across the globe for almost 15 years. Until they become available, zinc oxide is the safest and single most effective broad-spectrum filter available in N. America.

Co-Authored by,

Sara Dudley and Dr. Denis Dudley

jennifer aniston, sun damage, wrinkles, bad skin

A Timeline for Sun Damage

How does the Sun really damage our skin on a cell by cell basis over time

So we have all witnessed the casual creep of an emerging sun burn. I once realized that I had

jennifer aniston, sun damage, wrinkles, bad skin

Some Tell Tale Signs of Sun Damage

missed a hand shaped section on my back when a wicked burn emerged several hours later and I bore the mark of a tanned handprint for a month later. So we all know the general gist of how it works- we expose ourselves to sunlight and if not properly protected- we get sunburnt or perhaps a perceived lovely glow. In the back of our minds, we know that perceived glow might turn on us. We can spot sun damage with its entailed leathery texture of skin, pigmentation, freckles (yes that is sun damage, no you are not born with them) wrinkles and laxity. However, what damage is done in the moment and immediately after. How is the trauma inflicted? For those who are curious, here is a timeline for sun damage beginning with the first part in this series- the sunburn.

 

Moment 0: Vasodilation

Imagine a pure and perfect length of unprotected naked skin, while the first few rays of sunlight reach out and touch it. It’s a fantastic sensation for many but the pleasure hides the unseen assault that is happening.

Of the UV light that is not absorbed by the ozone layer, 5% of it is UVB- the burning rays. Think of UVB as being the heavy weight brute of the UV family. They pack a heavy punch that cause an immediate reaction. Immediately, the UV light triggers vasodilation, meaning a surge of blood rushes to the skin. This explains why you see an immediate reddening of the skin. However, this merely a first glance of what is to come as the more pronounced erythema (skin reddening) will appear 1 hour later and then peak between 24-48 hours.

If the skin is truly naked and without any form of protection, then the other 95% of UV light in the form of UVA will begin its more insidious invasion. Studies have shown that UVA also has an effect on vasodilation- however, it’s effect tends to peak after 72 hours. If you find your sunburn peaking or continuing substantially 3 days after exposure, it might be a good indicator that you were unprotected against UVA light in addition to UVB. This very often happens during those cloudy days where you receive the unexpected worst sunburn of your life.

Multiple studies have been conducted to find ways to mediate UVB and UVA caused erythema. Aspirin due to its possible inhibition of a fatty acid called prostaglandin showed the best improvement for UVB caused erythema. It did not show the same improvement for UVA caused erythema- leading researches to conclude that a different physiological effect was occurring with UVA based vasodilation.

Other research also showed that the DNA of skin cells are one of the main targets of UVB light.

DNA, target, UV damage,

UV Light Goes Straight for Your Skin’s DNA. Bulls-eye!

In other words, DNA are like sponges that soak up UV light, which causes a multitude of issues. DNA’s exposure to UV light immediately coincides with the production of a DNA repair enzyme that leads to a reduction in erythema. This means that from Moment 0 of UV exposure- an intricate anti-inflammatory response is triggered as the body fights to repair itself.

There is an upside to sunburn, as unpleasant as it sounds- you can consider it an undeniable warning sign that you should get out of the sun.  The issue with many high SPF sunscreens is that they mute that early detection system but do not necessarily follow up with the requisite UVA protection to keep other forms of skin damage at bay.

Something to think about until next time when we explore the physiological response within your skin as sun damage progresses.