After our previous article on sunscreen, our readers took to Facebook with even more questions! From wanting to know what the deal is with toxins in sunscreens to how to protect your eyes from the sun—you asked, so we’re answering.
We passed your burning (sorry, couldn’t resist the pun) questions along to Adrienne Haughton, MD, a board-certified dermatologist and assistant professor of dermatology at Stony Brook University School of Medicine in Stony Brook, New York, so that you can enjoy some worry-free fun in the sun.
There's a lot of talk about toxins in sunscreen. What does this mean exactly? Can you recommend any particular products without toxins in them?
What most people mean when they say "toxins" is oxybenzone. The controversy arises from the fact the Environmental Working Group and other organizations have raised concerns about oxybenzone, citing that it might be absorbed by the skin and, through a hormonal mechanism, might potentially cause damage to cells in the skin. The American Academy of Dermatology and the FDA have both deemed the use of sunscreens containing oxybenzone safe [see editor's note below]. I personally believe products containing oxybenzone are safe and recommend these products to my patients. For those who choose to avoid oxybenzone, I suggest the following: Blue Lizard, California Baby, CVS with zinc oxide, Kiss My Face (paraben-free), Neutrogena Sensitive Skin, and Olay Daily Defense.
I’ve heard that because we often don't apply sunscreen as well as we should, the labeled SPF is not as good as it claims. Should we look for sunscreens with certain ingredients for better protection?
The label is correct when the products are applied correctly. Be sure to apply one ounce (the amount to fill a shot glass) of sunscreen thirty minutes before exposure to the sun and then reapply every two hours or after swimming. Look for products labeled broad spectrum (UVA and UVB coverage), as well as those with UVA stabilizers such as helioplex or mexoryl, which extend the amount of time that the sunscreens are effective. It is important to realize that sunscreens do not continue to work if they are removed by water, sweat, or towel-drying. For example, Neutrogena waterproof spray sunscreen, which contains helioplex, states on the label that it is effective for up to eighty minutes in the water but to reapply after eighty minutes of swimming or sweating, after towel-drying, and at least every two hours.
Is it possible to have vitamin D deficiency through excessive sunscreen use?
Yes, the use of sunscreen may limit the production of vitamin D by your skin. Based on the increased risk of skin cancer from the sun, it is not recommended that people get vitamin D from natural sunlight or tanning beds. Vitamin D can be obtained through a healthy diet of vitamin D-rich foods, such as salmon, milk, and eggs, and supplements as needed. The recommended dietary allowance for vitamin D is 600 IU for children, teenagers, and adults one to seventy years old.
Do I need to apply sunscreen every day, even if I’m not going to the beach?
There is no question that wearing sunscreen protects against skin cancer and wrinkles. Everyone should apply sunscreen every day to all exposed parts of their body. UVA is present on a cloudy day and penetrates window glass; therefore it is important not to forget to apply sunscreen to your hands since you are exposed to UVA through the windshield of a car and the driver’s side window. It is also important to remember that regular clothing does not have a high SPF. A traditional white T-shirt has an SPF of 4, so the idea that you’re protecting yourself by swimming in a shirt only works if that shirts contains scientifically confirmed SPF.
What about my eyes?
The same advice above applies to your eyes as your skin. UVA penetrates window glass and therefore I would recommend wearing sunglasses frequently to decrease your risk of developing ocular melanoma.
Editor's note: Oxybenzone is a compound used in most popular sunscreens. The research on the chemical is limited, and scientists don't have enough evidence yet to firmly claim that sunscreens with oxybenzone are unsafe.