| New Age Skin Research Foundation's Article on Sunscreens - Patient Education Resource. |
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Why should I use sunscreen?
Ultraviolet radiation from the sun can have deleterious effects on the skin. Sunscreens contain active ingredients that act as ultraviolet filters. They have the ability to block UVB radiation that typically causes sunburns and UVA radiation that may be responsible for skin cancers.
Do sunscreens protect against skin cancer?
As of now, there is no definitive answer to this common question. The rationale behind those that believe sunscreens can be attributed to an increase in cancer is that sunscreens have caused individuals to have a false sense of security when it comes to protection from ultraviolet radiation. Many individuals who apply sunscreen feel they are being protected from the sun and therefore increase their time of exposure to UV radiation beyond what it would have been without sunscreen. The accumulation of this increased ultraviolet radiation exposure is what may be the culprit for the increased rates of skin cancer. On the other hand, experiments have shown that the active ingredients in sunscreen may be extremely beneficial in blocking out the harmful ultraviolet radiation that can lead to skin cancer. Further studies need to be conducted especially because the populations used for current studies are those that have been unprotected from ultraviolet radiation for years. Studies in the future can focus on participants that have been continuously protecting themselves throughout their lives, and will hopefully shed some light on this controversial issue.
Does SPF 30 have the double the protective powers than SPF 15?
No. SPF 30 deflects 97% of the suns burning rays, while SPF 15 deflects 93%. Therefore there are only minor increases in the deflecting ability as the protection factor increases.
Is sunscreen as effective after application?
Sunscreens tend to be less effective after application for various reasons. The effectiveness of sunscreen product can be reduced by sweating, friction, water immersion, or any other force that has the potential to remove the product from the surface of the skin. Failure to coat the entire surface of the body or removal from rubbing or sweating can create a lack of sunscreen, leaving the skin unprotected. The uneven topography of the skin, consisting of peaks and valleys, poses a challenge to uniform application of sunscreen. Excess product can accumulate in the valleys, while the peaks contain little to no coating. Also, not all sunscreens are created equal, therefore some may have higher substantivity (remain on the skin) than others or confer greater protection. The SPF can also be misleading to the consumer because it will only provide consistent sun protection under optimal conditions which include minimal perspiration, low water contact, low humidity, minimal activity, no wind, and thick film application. In reality sunscreen is not worn in these conditions which can lower the sunscreen's protective performance and leave the consumer susceptible to solar radiation.
Is there a specific time when I should avoid long term exposure to the sun?
Yes. The most susceptible times for sun damage occur in the summer during the hours of 10am-2pm.
What is the best SPF for my skin type?
- Never tans, always burns easily (e.g. Irish)
- Tans slightly, burns easily (e.g. Fair-skinned, blond hair, Caucasian)
- Sometimes burns, tans gradually and moderately (e.g. Mediterraneans and some Hispanics)
- Burns minimally, always tans well (e.g. Darker Hispanics and Asians)
- Burns rarely, tans deeply (e.g. Middle Easterners, some African Americans, Asians)
- Almost never burns, deeply pigmented (e.g. some African Americans)
Have there been any new advances recently in sunscreen technology?
More efficient and safe sun screening ingredients have been developed for improved skin protection. These sunscreens have highly new efficient absorption or reflecting capabilities throughout the ultraviolet wavelengths, and in some instances infrared wavelengths. Although they already in use in Europe, they are currently being approved by the FDA for their use in the United States.
Type |
Sunscreen active COLIPA no./INCI name |
Trade Name (Supplier) |
Peak Wavelength
Absorbed (nm) |
*Seeking Approval or
In Use |
UVB |
S69 EHT
S78 DBT
S74 BMP |
Uvinul T 150 (BASF)
Uvasorb HEB (3V Sigma)
Parsol SLX (Roche/DSM) |
315
310
315 |
Europe, USA *
Europe
Europe, Japan , USA * |
UVA |
S71 TDSA
S80 DPDT
DHHB |
Mexoryl SX (L'Oreal) Neo Heliopan AP (Symrise)
Uvinul A Plus (BASF) |
345
340
355 |
Europe
Europe
Europe |
UVB and UVA |
S73 DTS
S79 MBBT
S81 BEMT |
Mexoryl XL (L'Oreal) Tinosorb M (Ciba SC) Tinosorb S ( Ciba SC ) |
300 and 345
310 and 360
300 and 350 |
Europe, Japan
Europe, Australia , USA*
Europe, USA * |
Abbreviations: COLIPA, European Cosmetic Toiletry ad Perfumery Association; INCI, International Nomenclature Cosmetic Ingredient.
Which method of application is most effective?
Today, sunscreen products are available in many forms including creams, sprays, ointments, gels, lotions and wax sticks. The type of sunscreen chosen is a matter of personal choice. The waxy stick products are useful for one's face because they are very substantive to the skin and resistant to removal by water and sweat. The flaw in using stick products is the fact that they cannot be spread easily once applied, therefore, are generally not appropriate for use over wide areas of the body.
The spray delivery method is attractive to many because, unlike the large amounts of grease in oily vehicles, the ethanol quickly evaporates, thus reducing the amount of residue on the skin. The ethanol-based sprays are also commonly used due to their clarity, fast drying nature, and pleasant cooling nature upon application. Spray products allow application onto hard to reach places. For example most people cannot reach portions of their back. Therefore a spray would be best for that area. Recently a new spray sunscreen came to the market that offers continuous spraying, making it even easier to apply and reapply sunscreen. There are some disadvantages that the consumer should recognize. The ethanol-based sprays can be slightly drying and irritating, and can burn if applied to a sensitive area such as the eyes. Rapid evaporation form the skin can decrease the SPF efficacy therefore offering less protection.
Sunscreen lotions and creams are the most common form of sunscreen product on the market. Lotions allow flexibility when selecting a sunscreen product based on efficacy, cost, skin feel, and irritants. The lotions and creams can also incorporate other ingredients into the formulation such as moisturizing agents and antiaging active ingredients. It appears that this can result in increased consumer compliance, which would additionally increase its efficacy.
Sunscreen wipes consist of sunscreen formulations absorbed onto a nonwoven substrate, which provides a convenient applicator for coating the skin uniformly. The problem underlying this delivery method is that the substrates can interact with the sunscreen active ingredients and other components of the formulation. It is vital that additional testing be carried out on wipe formulations to avoid these interactions.
Does sunscreen prevent adequate production of vitamin D?
Although ultraviolet radiation is responsible for the production of vitamin D in the skin, the use of sunscreens do not lead to a decrease of vitamin D. Studies examining vitamin D status in populations using sunscreen products have not found deficiencies in vitamin D or clinical evidence of such a deficiency. Instead of using the sun as a primary source of vitamin D synthesis, supplements can provide adequate intake as well as milk and orange juice fortified with vitamin D. The US Department of Agriculture recommends 200 IU/d for children and younger adults (<50 years old), 400 IU/d for older adults (>50 years old), and 600 to 800 IU/d for the elderly (>70 years old). Eight ounces of fortified milk or orange juice contains 100 IU (2.5 g), the amount of vitamin D found in approximately half a teaspoon of cod liver oil. This issue has become less significant due to the fact that most foods are now enriched with vitamin D, resulting in a low occurrence of vitamin D deficiency.
How often should I reapply sunscreen?
Sunscreens should be applied to dry skin 15-30 minutes before going outdoors so the sunscreen has the ample time to bind to the skin. The first reapplication should take place about 20 minutes after the initial application, to boost protection and ensure good coverage. When applying sunscreen, pay particular attention to the face, ears, hands and arms, and coat the skin liberally. One ounce, enough to fill a shot glass, is considered the amount needed to cover the exposed areas of the body properly. Be careful to cover exposed areas completely because a missed spot could mean patchy, painful sunburn. Don't forget that lips get sunburned too, so apply a lip balm that contains sunscreen, preferably with an SPF of 15 or higher. Sunscreens should be re-applied every two hours, after swimming, perspiring heavily, or physical contact. If there is physical abrasion, reapplication should take place even earlier.
What can I do to become more compliant?
There are many reasons people fail to adequate apply sunscreen. The most common reason is that they think sunscreen is sticky. Higher SPF sunscreens tend to be stickier. Try using a lower SPF, such as SPF 15 instead of 30, which only has a minimal decrease in photoprotection. If the higher SPF is too sticky, it will be used less frequently and subsequently offer less protection than a lower SPF sunscreen that is used more frequently. Lower SPF sunscreens also tend to be less oily. Lower SPF decreases the amount of residue left on the skin from the active ingredients. One can use a sunscreen-containing facial foundation or can apply facial powder over the sunscreen to minimize the facial shine.
Patients often complain of feeling hot and sweaty when they wear sunscreen. This is due to some of the active ingredients in the sunscreen that tend to convert ultraviolet radiation into heat. Try using zinc oxide or titanium dioxide which do not produce heat.
There is a common belief that sunscreen is oily and can cause acne. Apply the sunscreen to a small area on the skin for a five consecutive nights to see if a reaction appears. Patients who are concerned about acne from sunscreen should avoid wearing sunscreen products for long periods of time and use sunscreen-containing moisturizer for daily application. Gel sunscreens should be avoided because they contain a polymer. Light-weight cream derivatives should be used and reapplied frequently for optimal protection.
| Panel: (we are currently updating names of the doctors/dermatologists participating in this panel) |
Acknowledgments
We acknowledge National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) of National Institutes of Health for the above content. Contributors include Robert Katz, M.D., Rockville, MD; Larry Miller, M.D., Chevy Chase, MD; Alan Moshell, M.D., NIAMS, NIH; Gary Peck, M.D., Washington Hospital Center, Washington, DC; and Maria Turner, M.D., National Cancer Institute, NIH.
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