Identifying Important Sunscreen Ingredients
The dangers of melanoma and realities of skin aging from UV exposure are now well-documented. Nonetheless, it is still difficult to get patients to wear sun protection every day. To ensure patients are getting the greatest benefits, it is important to understand what ingredients to look for and why. In order for any sunscreen product to provide adequate sun protection, it must be considered broad-spectrum, meaning it protects from both UVA and UVB radiation, both of which are responsible for DNA damage, skin cancer, and aging. When developing a formula for sunscreen, one of four sunscreen agents must be included in the formulation. These mandatory ingredients include avobenzone, titanium dioxide, ecamsule (aka Mexoryl™), and zinc oxide. If there is not at least one of the aforementioned ingredients within a sunscreen product, it will not provide adequate protection from UVA rays. There are a number of sunscreen agents that protect the skin against UVB rays and these include but are not limited to; homosalate, octinoxate, octisalate, octocrylene, oxybenzone, and padimate O. While there are many to choose from, one is not necessarily more effective than the other. The formulation as a whole and patient compliance determines a product’s reliability.

Navigating Statistics
Helping patients understand the critical importance of wearing sun protection every day, not just at the beach, is a constant struggle. The public’s access to information has increased greatly through the Internet and media. This is good, but can also cause confusion. There is often research preformed that may lead to inconclusive or unclear outcomes. These results can still be found by the consumer and may be misunderstood or misconstrued as absolute fact. A good example is a small study performed in 2006 at the University of California, Riverside, which suggests some sunscreen ingredients cause free radicals in the skin, therefore making them harmful. Most dermatologists discount this as a small and inconclusive study, while a few agree with its findings. This leaves the average consumer with a difficult decision. Do they listen to what they have been told for years about daily use of a moisturizer with SPF or do they forgo its use to avoid free radical damage? Certainly with the dramatic increases in melanoma cases, avoiding daily sunscreen is not a safe or smart option. Even if the Riverside study eventually proves to be valid, using products that contain antioxidants easily overcomes the suggested problem with sun protection use. Sunscreens that contain antioxidants or, even better, topical treatment products that contain beneficial doses of multiple free radical-fighting ingredients are great additions to every daily skin care regimen. This allows patients to get the sun protection they need with the added benefit of antioxidants to negate any free radical formation.

Promoting a Healthy Matrix with Antioxidants and MMPi
Free radicals are thought to play an intricate part in the cell mutations that lead to skin cancer. Daily use of free radical-quenching topical antioxidants is important to healthy skin, even if not intentionally getting sun exposure. Some of the best UV protective topical antioxidants are vitamins C and E. Numerous studies have demonstrated that topically applied vitamin C protects the skin from reactive oxygen species (ROS), a very active free radical, as well as from the erythema and sunburn cell formation caused by UV exposure. Vitamin C also shows photo-protective benefits against both UVA and UVB rays. Vitamin E is important for maintaining healthy skin. Ozone and pollution have both been shown to deplete the amount of vitamin E in the stratum corneum. This makes topical application of this beneficial antioxidant even more important. Vitamin E protects the lipids in the cell membrane. During this otherwise beneficial process, the vitamin E molecule is converted into a free radical itself. Vitamin C recycles this tocopheryl quinine free radical back into a useful antioxidant. This synergy of action makes using both vitamins together extremely advantageous.

Useful Antioxidants:

• Glutathione
• Ergothioneine
• Proanthocyanidins
• Ascorbic acid (vitamin C)
• Beta-carotene
• Tocopherol and tocotrienols (vitamin E)
• Resveratrol
• Green tea extracts
• Soy extracts

In addition to antioxidants, it is important to infuse the skin daily with matrix metalloproteinase inhibitors (MMPi) ingredients to protect from free radicals. This is a family of ingredients that disables the metalloproteinase (MMP) enzymes that degrade important structural proteins in the skin. MMP enzymes, such as collagenase and elastase, are responsible for the breakdown and recycling of older and unusable fragments of proteins like collagen and elastin. MMP are beneficial to a certain extent, as they rid the skin of this protein ‘waste.’ However, because MMP production increases with exposure to UV rays, pollution, free radicals, and other external factors, they can be responsible for an unwanted breakdown of healthy proteins. MMPi are ingredients that maintain the current balance within the extracellular matrix by inhibiting the over-activity of these MMP enzymes. These inhibiting ingredients allow for MMPs to rid the skin of the unwanted proteins, but maintain the healthy and necessary collagen and elastin.

Common MMPi:

• Retinoids (vitamin A)
• Proanthocyanidins
• Vitamin E
• Aloe Vera
• Bisabolol
• Resveratrol
• Soy Proteins
• Epigallocatechin Gallate (EGCG)
• Ascorbic Acid (vitamin C)

The Vitamin D Question
Vitamin D is responsible for healthy bone mass and strong muscle function. The body’s main source of vitamin D is created through a chemical reaction in the skin due to sun exposure. It is thought that higher levels of vitamin D in the body may provide health benefits including reduced incidence of arthritis, Type I diabetes, and some cancers. Some medical professionals now believe that our more consistent use of sunscreens may be responsible for people having vitamin D levels that could be too low to enjoy these potential health benefits. Unfortunately, short durations of unprotected sun exposure each day are now being recommended by some well-intentioned individuals to increase vitamin D levels. The amount of time varies based on time of year, skin type, and location. The main challenge is that UV rays absolutely cause cancer and skin aging, so any and all unprotected exposure is dangerous. A more safe approach to achieve the necessary amount of vitamin D for healthy body function is a diet rich in oily fish such as mackerel, salmon, and sardines; fortified milk, orange juice, and yogurt; and/or oral supplementation of 1,000 I.U. per day.

Tips for Staying Safe in the Sun
Spending time outdoors, whether during the summer or winter, increases risk of over-exposure to the sun. Full coverage surfer rash guards that can be worn with a bathing suit can significantly reduce the amount of UV exposure the body receives while on the water. There are also certain lines of clothes, hats, and swimwear that are specially designed and offer built-in UV protection. Manufacturers display an ultraviolet protection factor (UPF), which measures how much UVA and UVB radiation the garment is able to absorb. Consumers should look for a UPF of at least 30 for adequate protection. In general, clothing will provide some protection from the sun. Clothing with denser fabrics and a tighter weave will protect more than light-weight fabrics. To determine how dense an article of clothing is, hold it up to the sun and see how much light comes through. The color of fabric also plays a part in protection; black fabric offers significantly higher UPF than white fabric because it absorbs more light. Denim naturally has a UPF of 1700 due to its tight weave and dark color. There are laundry additives that can be washed into clothing to increase the UPF of the fabric. Always wear hats and sunglasses to shield the skin and eyes from damaging UV rays. Look for wider brimmed hats and sunglasses with special UV coating to ensure the highest amount of protection possible. Protective films are available for car windows that reduce the amount of UVA and UVB exposure while driving by over 99 percent. Unfortunately UVA rays can easily pass right through glass making commuting a dangerous and aging process.
It is important to keep in mind that sand, water, and snow reflect and intensify the sun’s rays by as much as 80 percent. Be sure to have adequate protection while swimming, skiing, playing sports, or walking on the beach. People often mistakenly think that because it is overcast or cool outside, the sun is not as strong. UV rays are capable of penetrating through clouds and remain constant year-round, regardless of the temperature or how bright it is outdoors. Another dangerous misconception is that because some people only get sun once or twice a year while on vacation, they are not a high skin cancer risk. Studies actually indicate the opposite and show that the intense sun exposure received during vacation may be more dangerous than the constant, daily exposure of those with outdoor professions. In fact, one blistering sunburn or five non-blistering sunburns more than doubles one’s risk of developing melanoma, making vacations one of the most crucial times to seek sun protection.

Enough of a Good Thing
Another way to increase your protection is to arm yourself with knowledge and avoid falling for some of the myths that often lead to the most severe sunburns. A common misconception is that applying more than one SPF product will increase the amount of SPF you receive, but this is not the case; you will only receive the amount of protection provided by the highest SPF applied. Extremely high ratings of SPF can also be deceiving, as SPF protection does not increase proportionally with an increased SPF number. An SPF 15 sunscreen protects the skin from 93 percent of UVB radiation, an SPF 30 sunscreen provides 97 percent protection, and an SPF 65 provides approximately 98 percent protection. There are no sun protection products that block out 100 percent of UV rays. No matter how high the SPF number of a product, it is important to reapply sunscreen every two hours if you remain exposed to the sun. Even highly water-resistant products are only designed to last 80 minutes, so always reapply after swimming or sweating.
A combination of UVA and UVB sunscreen ingredients and antioxidants will provide adequate protection, but only if applied correctly. According to the American Academy of Dermatology (AAD) at least one ounce (a full shot glass) of sunscreen per application is needed to cover the exposed areas of the body in order to get the full amount of protection a product is capable of providing. It is also important to realize that skin of all colors is damaged by UV rays. Even the darkest skin can burn and develop skin cancer. In fact, Bob Marley died of the deadliest form of skin cancer, melanoma. If you or any of your patients have a suspicious spot or mole that is bleeding or changing in size, shape, color, or texture, they should have it examined by a dermatologist.
Although, the abundance of information on this subject can be confusing, choosing and correctly applying a product with an SPF of at least 15 that contains a blend of antioxidant and MMPi ingredients will provide your patients with adequate daily sun protection. This is just one step in the journey toward healthy skin. Taking these measures will ensure you and your patients preserve the important structural proteins and quench the skin with free radical-fighting ingredients to reduce the risk of skin cancer and promote healthy, beautiful skin. 

Jennifer Linder, M.D., serves as Chief Scientific Officer for PCA SKIN®, guiding all product development and clinical trials for the company. A board-certified dermatologist and a fellowship-trained skin cancer surgeon using the Mohs micrographic technique, Dr. Linder is one of the foremost U.S. experts in the use of the cosmetic filler, Sculptra. She holds a clinical faculty position in the Department of Dermatology at the University of California, San Francisco