Sunscreens for sun sensitive people

Finding a sunscreen that works for your light condition can make a huge difference in one's life. I know it did for me. 

Overview

Understanding how sunscreens work is key to finding the right sunscreen for your condition. Most sunscreens protect only against UVB  light.   But light spectrum  has  different wavelengths: UVA, UVB, visible, and  infrared and more. Depending on your medical condition, you may be sensitive to more than one type of light. For example, people with lupus are often sensitive to both UVA and UVB type light. People with solar urticaria and polymorphous light eruption can be sensitive to UVA, UVB and visible light. Some people are even sensitive to infrared light. 

You need to match up a sunscreen with your personal light sensitivity. Most people have already tried a high SPF sunscreen, but most sunscreens only protect against UVB light (measured with SPF).  So the next step is to try sunscreens that protect against UVA light;  UVA protection is measured with a PPD rating.  The higher the PPD rating, the better. Because of restrictive FDA regulations in the U.S., the best sunscreens for UVA protection are only sold in Europe and Canada.  In research studies, Anthelios XL, SPF 60, PPD 28 (Europe), was found to be the best sunscreen for lupus patients (sensitive to both UVB and UVA light).

Once you have the sunscreen, you need to apply enough sunscreen and store the sunscreen properly, and discard the sunscreen when too old. Finally, we take a detailed look at SPF and PPD ratings. A high SPF sunscreen rating of 50 should  theoretically protect you 50 times as long in the sun as without the sunscreen. But in real life, people don't apply enough sunscreen which reduces the theoretical rating considerably.

Understanding the different types of light/radiation and their relationship to sunscreens

The solar spectrum is composed of different types of radiation. Radiation is energy that travels and spreads out as it goes. There are many different types of radiation: ultraviolet (UV), visible light and infrared (IR) and more. The different types of light/ radiation are defined by their wavelength measured in nanometers (nm). The sun is a source of invisible ultraviolet (UV) radiation, because it is the UV rays that cause our skin to burn! UV light also causes the heat we all recognize. Ultraviolet light  is divided into UVA, UVB and UVC ranges. UVA light is further divided into UVAI and UVAII ranges.  [Electromagnetic Spectrum]  More at Photobiology for Kids.

UVB (B for burning), measured with SPF:  ( 290-320nm)

• Most commercial sunscreens protect against UVB.
• UVB sunscreen rating - measured with the Sun Protection Factor (SPF) rating. SPF measures how well a sunscreen protects you against sunburn and UVB light.  Theoretically, a sunscreen with an SPF rating of 10 should allow you to stay in the sun ten times longer than without sunscreen.
• UVB mostly burns the skin resulting in sunburn, but does contribute to skin aging and skin cancer. Everybody is sensitive to UVB.

UVA (A for aging), measured with PPD:  (340-400nm)

• Sunscreens that protect against both UVA and UVB light are called broad spectrum sunscreens.
• UVA sunscreen rating - measured with PPD rating which measures tanning or Persistent Pigment Darkening which measures how well a sunscreen protects you against UVA light.  Theoretically, a sunscreen with a PPD rating of 10 should allow you to stay out in the sun ten times longer than without sunscreen.
• UVA mostly ages the skin and causes skin to tan.
• You are sensitive through glass like in the car. (Window glass blocks virtually all UV-B and only a portion of  UV-A energy.)
• UVA protection is now offered in many sunscreens, but unfortunately (in the U.S.), the labels usually provide no indication of the level or wavelengths of UVA protection. 

Visible light or blue light, no rating: (400-700nm)

• This is the visible radiation that we can see.
• Visible or blue light rating - there is no rating and sunscreens for visible light are very rare. See the page on Visible light sunscreens.
• You are probably sensitive to indoor lights.

Infrared light, no rating: (above 700nm)

• Infrared light: no rating, and I read somewhere that there is a sunscreen for people sensitive to infrared light.

UVC:  (200-290nm)

• UVC does not reach us because it is absorbed by the atmosphere.[ Lupus Foundation of America]

What is your light sensitivity and medical condition? 

Depending on your sun sensitivity, you may be sensitive to different wavelengths of light including UVA, UVB and visible light. Think of having a roof over your head with three holes in it- one hole for UVA light, one hole for UVB light, and one hole for visible light, and it is raining. If you are sensitive to UVB, UVA and/or visible light, normal sunscreens which only protect against UVB light may not protect you, and you will get burned by the UVA and/or visible light. So searching and finding the right sunscreen for your condition can make a huge difference in your sun tolerance. 

What is your sun sensitivity? Most people are sensitive to UVB. If you have problems through windows, then you might be sensitive to UVA. If you are sensitive to indoor lights, then you might be sensitive to visible light (rare). Some people are sensitive to infrared.

Each person has their own unique own light sensitivity.  One person with solar urticaria may be only sensitive to UVB, while another person with the same condition may be sensitive to UVB, UVA and visible light. The list below describes sun sensitive conditions (photodermatoses) and the possible light sensitivities. 

Solar urticaria: UVA,  UVB,  or visible Solar urticaria can be induced by UVA and UVB,  or visible light. [http://www.skintherapyletter.com/download/stl_7_7.pdf] Polymorphous light eruption (PMLE): UV-B, UV-A,  or visible PMLE can be sensitive to  UV-B, UV-A,  or visible light. UVA induces polymorphous light eruption (PMLE) in most patients, although it has been shown to reduce PMLE in others.   [Sunscreens: The Importance of UVA Protection]    Lupus: UV-B or UV-A Cutaneous lupus erythematosus is also exacerbated by UVA light. [Sunscreens: The Importance of UVA Protection]   Drug photosensitivity: UV-B, UV-A (most) [Best Practice of Medicine][ Menter] Albinism: UVA and UVB [Emedicine] Porphyrias: UVA, UVB and visible (400–650) [ Menter] Photochemotherapy: PUVA (320–380),PDT (400–700) [ Menter]

Sunscreen containing UVA filter Mexoryl XL (upper part of the arm) provides significant protection against the induction of skin lesions in PMLE patients.[Skyscape]

Choosing a sunscreen  for your light sensitivity:

The objective is  match up your unique light sensitivity to a sunscreen that protects you. Most sunscreens protect against UVB light which is measured by the SPF rating. Some of the more advanced sunscreens protect against UVA light which is measured with a PPD rating. Sunscreens that protect against visible or infrared light are very rare. If you are sensitive to visible light,  finding a sunscreen is much more difficult; see the  page on Visible light sunscreens.  

You probably have already tried sunscreens with high SPF ratings and UVB light protection, so the next step is to find or try a sunscreen  to protect against UVA light to see if it helps. For UVA light protection, look for a sunscreen with high PPD ratings.  In one U.S. study, sun care products claiming UVA protection on the bottle label only  had UVA protection in testing from as little as 6% to as much as 52%. [Rosenstein]

Europe has the best sunscreens for protecting against UVA light with Canada  being second best as you can see in Table 1 by the PPD ratings. Unfortunately, the U.S. does not allow the new and better sunscreen ingredients for UVA light protection. Also the PPD rating is not used in the U.S. Although sunscreens in the U.S. may claim to have UVA protection,  U.S. sunscreens may only protect against a tiny portion of UVA, leaving you thinking you are protected when you are not. For that reason, you may want to try the Canadian or European sunscreens instead.

Table 1: PPDs of sunscreens

based on http://www.makeupalley.com/user/notepad/nora80/ and other sources
* Unfortunately,  PPD is not used in the U.S..

Ingredients to look for good UVA protection:

To achieve a broad range of protection across the light spectrum, sunscreen manufacturers use several ingredients. Some ingredients are good in the UVB range, some are good in the UVA range, some ingredients stabilize other ingredients. The web page on Sunscreen Ingredients describes which ingredients protect across which part of the UVA and UVB range. In a small study in Germany that involved people with extreme sensitivity to UVA, products with Mexoryl plus Parsol proved by far the most protective. Products with other ingredients, including Parsol and titanium dioxide, worked only half as well.  In another research study, the best sunscreens for both UVB and UVA light contain Mexoryl XL, Mexoryl SX, Butyl Methoxydibenzoymethane (Parsol 1789). [Stege] (For more about sunscreen research, see the Sunscreen Research web page.)  The ingredients that provide a high level of  UVA light protection are only allowed in sunscreens in Europe and Canada, and most are not available in the United States. In addition to the previously mentioned ingredients, other ingredients such as Tinosorb (S  or M) are effective in the UVA range. Some brands with Mexoryl are Anthelios XL and Capital Soleil (both made in France). They also contain Parsol 1789 and a range of other protective ingredients. To make life even more confusing, one ingredient can have many different names, so the best measure of UVA light protection is the PPD rating.

Select sunscreens with a high PPD rating for good UVA protection

Look for a sunscreen with a high PPD (measure of how well it protects against UVA light) and the ingredients mentioned above.  The following is a suggestion of what sunscreens to try based on sunscreen research and reviews.  Also see the group's Sunscreen Reviews.

Europeans sunscreens (best):
Some ingredients are only available in Europe.

Anthelios 60 XL cream UVA: IPD 80, PPD 28
by Laroche-Posay with Mexoryl XL, Mexoryl SX, especially designed for those who need the strongest possible sun protection Protection  [Stege]
Reviews: For 16 Against 11 [MakeupAlleyPPDs]

La Roche Posay Anthelios Dermo-Kids Crème 60 PPD 28
Mexoryl XL & SX, Tinosorb S, BMDM, TO2 
Reviews: For  15 Against 4  [MakeupAlleyPPDs]

Vichy Capital Soleil Ultra Fluide SPF 60 PPD 20
Mexoryl XL & SX, Tinosorb S, TO2, Ethylhexyl triazone, BMDM
Reviews: For  8 Against 2 [MakeupAlleyPPDs]

Canadian sunscreens: (next best)
Some ingredients are only allowed in Canada. 

Anthelios L, SPF 60, PPD 15.
Solar intolerance sunscreen by LaRoche-Posay which contains Mexoryl SX, Parsol 1789 and titanium dioxide . Active Ingredients: 4-Methylbenzylidene Camphor 5%, Titanium Dioxide 4%, Butyl Methoxydibenzoymethane (Parsol 1789) 3.5%, Terephythalylidene Dicamphor Sulfonic Acid (Mexoryl SX) 3.3%[http://www.skintherapyletter.com/download/stl_7_7.pdf ]

Vichy Capital Soleil SPF 60, estimated PPD 15
Ingredients: mexoryl SX, 3.5% BMDM, 4% TiO2, 5% 4-MBC.
Vichy SPF 60 appears to be the most cosmetically elegant, highly protective Canadian sunscreen. It is fragrance-free, unlike LRP Anthelios L SPF 60.

Ombrelle SPF 60 with Mexoryl (some complain of it being sticky)

Canadian sunscreens with Mexoryl: http://www.feelbest.com/pages/mexoryl.aspx 

United States sunscreens: (not as good)
Some of the best UVA ingredients are not allowed in the U.S.

Total Block SPF 65: 
Benzophenone-3, Octyl Methoxycinnamate,Octocrylene, Titanium Dioxide, Zinc Oxide (Total Block has not been in any  research studies that I know of.)

Applying and using Sunscreen

Apply sunscreens to dry skin one half hour before going outside. Shake the bottle well and apply thickly and thoroughly. 

"Teaspoon Rule"
Be sure to use enough sunscreen. Most people only use half as much as they are supposed to.  As a rule of thumb, use one teaspoon to cover the face, neck, and ears; one teaspoon to cover the front; one teaspoon to cover the back of the body; and one teaspoon for each arm or leg not covered with clothing. A typical twist off cap from a soda bottle is about one teaspoon. If you only use half as much sunscreen as you should, you are only getting half the protection. [Schneider] Don't forget to put sunscreen on your ears, the base of the neck, the tops of feet, and the backs of knees.  One study on photosensitive patients showed that they only applied 1/4 of the recommended amount of sunscreen.[ Azurdia]

Reapply every 2 hours. Reapply after swimming or sweating. [American Cancer Society]   Most sunscreens are very fragile and easily rubbed off. Some sunscreens suggest that  you reapply after 2, 3 or 4 hours. Some chemical sunscreen ingredients breakdown and no longer work after a while.

Don't store sunscreen in the car and other places, where temperatures may get high. Heat may change the chemical composition of sunscreens.  Throw out your old sun block. The chemical composition of sunscreens can change with age, and it may no longer perform as stated on the bottle. Check the expiration date. 

Understanding SPF and PPD values of sunscreen ratings

To review,  SPF measures how well a sunscreen protects you against sunburn and UVB light.  Theoretically, an SPF rating of 10 should allow you to stay in the sun ten times longer than normal. Persistent Pigment Darkening (PPD)   measures how well a sunscreen protects you against UVA light.  Theoretically, a PPD rating of 10 should allow you to stay out in the sun ten times longer.

People with extreme photosensitivities may have reactions in just a matter of minutes, so we need the highest SPF and PPD ratings possible. In real life, people rarely get the SPF or PPD rating on the sunscreen bottle because: not enough sunscreen is put on in the first place, or sunscreen  is wiped  or sweated off, or sunscreen is left on too long and is no longer effective etc. Most people only apply enough sunscreen to achieve an SPF of about a third or even a quarter of the level stated on the product. [eMJA  

As an example, take someone who reacts to the sun in 5 minutes that uses an SPF sunscreen of 30. But they only put on a third as much as they should have. Now assume that the SPF rating of 30  is reduced  by one third to a value of  10 because he or she didn't apply enough sunscreen. An SPF of 10 is supposed increase  a person's tolerance time in the sun by a multiple of 10, so they would be able to spend 50 minutes in the sun. 

     5 minutes x 10 =50 minutes,  

where 10 is the SPF rating, 5 minutes is the the person's sun tolerance without sunscreen, and 50 minutes is the person's theoretical sun tolerance with sunscreen. 

Theoretically for SPF or PPD values above 30, light protection does not increase significantly  as shown in Table 2.   For example, doubling the SPF from 50 to 100 only blocks an additional 1% more light.  Different organizations argue that there is no need for an SPF greater than 30, and some  European regulations only allows sunscreens to have a maximum SPF rating of 50+, and no higher.  But if we added the real life factors, then all of those theoretical ratings get reduced by more than half  to one fifth of the original SPF rating.   As was shown in the previous example, those of us with extreme sun sensitivity and short sun tolerance time need those extremely high SPF ratings. On the other hand, critics argue that it is difficult to test high SPF ratings.

Table 2: Protection of sunscreens by SPF rating and PPD rating
(Most people do not apply enough sunscreen and  can reduce SPF values to one third or one fourth the value on the bottle.)

More information

Makeup Alley has a good page on sunscreens with PPD ratings and where to buy them. 
http://www.makeupalley.com/user/notepad/sunscreens/ 

Salicylate-free sunscreens. Look for UVA and UVB protection.
http://www.psha-inc.com/guai-support/sf/Sal-Free/Sunscreens.htm 

References:

[Schneider] Schneider J. The teaspoon rule of applying sunscreen. Arch Dermatol.2002; 138: 838-
839

[Azurdia] Sunscreen application by photosensitive patients is inadequate for protection.
Azurdia RM, Pagliaro JA, Diffey BL, Rhodes LE., Br J Dermatol. 1999 Feb;140(2):255-8.PubMed

[Menter] Clothing as solar radiation protection., Menter JM, Hatch KL., Curr Probl Dermatol. 2003;31:50-63.

[Rosenstein] Rosenstein BS, Weinstock MA, Habib R., Transmittance spectra and theoretical sun protection factors for a series of sunscreen-containing sun care products. ,Photodermatol Photoimmunol Photomed. 1999 Apr;15(2):75-80.Entrez PubMed