To Screen or Not to Screen: The Facts About Sunscreen
by Dr. Allison Ziegler, ND
It’s a hot summer day – not a cloud in the sky or a breeze in the air. You decide to take a trip to the beach to bask in the sun and enjoy the warm day. In preparation, you grab your beach bag and fill it with all the beach necessities – towel and bathing suit, a water bottle, some snacks, sunglasses and hat. Before you leave you decide to lather on the sunscreen as the morning news indicated a high UV index. All prepared for the day, you make your journey to the beach unaware that the “safety” benefits listed on your sunscreen and what it contains may be causing more harm than good.
Being that May is skin cancer awareness month, a review on the importance of skin protection is timely. Sunscreen has long been known as the protective mechanism against sunburns, skin cancer and declining skin health. More recently we know that beyond preventing sunburns, there is little known about the safety and efficacy of sunscreen. In 2011, the Food and Drug Administration (FDA), which is responsible for regulation of products, released sunscreen regulations; however, they still allow the products to contain potentially hazardous ingredients and make exaggerated claims. As a result, it is important to understand what to look for when selecting sunscreen products.
Getting the Facts:
The common form of vitamin A added to sunscreens is retinyl palmitate. Vitamin A is a popular anti-oxidant used in skin products in order to prevent or slow skin damage and aging. The FDA has recently conducted a study that showed in the presence of sunlight, topical application of retinyl palmitate increases the development of cancerous skin lesions. It is thought that when vitamin A is exposed to sunlight, free radicals are formed, which damage skin cells and predispose them to cancer development. This becomes an issue with the vitamin A content in sunscreens as opposed to other skin care products because of the vast sunlight exposure endured while wearing sunscreen. Furthermore, claims made by sunscreen products that they protect against skin cancer become a concern; as such, products may in fact increase risk of skin cancer development.
Oxybenzone is added to sunscreen to absorb UV-B and UV-A rays; however, it is known to penetrate the skin and can lead to development of allergies and disrupt hormone balance. It is strongly urged to avoid use of oxybenzone containing products especially in children because of the hormone disrupter properties.
SPF, or Sun Protection Factor, of sunscreen is a measure of effectiveness of the sunscreen, meaning that the higher the SPF, the more protection against UV-B radiation. The FDA has prohibited companies from indicating SPF 50+ because there is lack of evidence that 50+ exhibits any additional protection and in fact may promote people to stay in the sun longer, thus increasing radiation exposure and damage. Despite the FDA’s efforts, companies continue to advertise SPF50+.
UV-A & UV-B Protection
UV-A and UV-B radiation are both responsible for skin damage; however, many conventional sunscreens do not protect against UV-A rays. UV-B rays only penetrate the outer skin layer and are primarily responsible for causing sunburns and non-melanoma skin cancer. UV-A rays penetrate deep into the skin to cause DNA damage increasing the risk of malignant melanoma. The sunscreens labeled as “broad-spectrum” are designed to block both UV-A and UV-B; however, many do not contain the ingredients to actually protect against the UV-A rays.
Sunscreens in the form of liquid or powder should be avoided because the health effects due to inhalation have not been investigated.
What to Choose
Mineral sunscreens tend to be the safest and effective choice. Mineral sunscreens (zinc and titanium) are stable in sunlight, do not penetrate the skin and tend to be the most effective at blocking UV-A radiation. Those who do not like mineral sunscreens are encouraged to try sunscreens with 3% avobenzone and products without oxybenzone (for reasons listed above).
Sun protection is important; however, sunscreen should not be the first-line protection mechanism. Use of protective clothing, hats, sunglasses and monitoring time of direct sun exposure are primary in reducing the risk of skin damage and skin cancer. Selecting a sunscreen more carefully can aid in the protection but should not be the sole action to do so.