Shedding Light on Sunscreen


by By Lisa Weiner /

Posted on July 17, 2009 at 10:03 AM

Updated Thursday, Nov 12 at 1:53 PM

About the Author

Portland freelance writer Lisa Weiner is a nurse practitioner and proud mother of a two-year-old boy. She has a passion for demystifying the world of health for her patients and readers. Her work has appeared in Clinician Reviews, The Jewish Review, Northwest Palate and the Oregonian.

We know that going out in the sun without sunscreen is bad news. Sunburns, skin cancer and premature aging are all caused by too much unprotected time in the sun. But when we dutifully head over to the drugstore to buy some sunscreen, we are faced with a dizzying array of choices.

To save us from spending the whole day in the sunscreen aisle (but, hey, at least then we don't have to worry about getting a sunburn), here is some important information to keep in mind when buying and using sunscreen:

Decoding Those Acronyms on the Bottle SPF (Sun Protection Factor) gives you a rough idea of how long you can stay out in the sun without burning. For example, if you would usually burn in 10 minutes, an SPF 15 will allow you to stay in the sun for 150 minutes without burning. The American Academy of  Dermatology recommends an SPF of 15 or higher.

Additionally, keep in mind that the sun gives off both UVA (Ultraviolet A) and UVB (Ultraviolet B) rays. UVA rays pass more deeply into the skin and are thought to cause premature aging and, possibly, skin cancer. UVB rays cause melanoma and other types of skin cancer. Look for sunscreen that says "Broad Spectrum" for protection from both kinds of rays.

Making Sense of Ingredients Sunscreen ingredients are either chemical or physical blockers of UV rays. Chemical agents absorb UV radiation and convert it into long wave radiation that is dispensed harmlessly. Physical agents--zinc and titanium oxide--work by reflecting and scattering UV radiation. Products containing physical agents are often called "sunblock" because of how they work.

Sunscreen safety is a hot topic. It is up to us as consumers to do our research, as the FDA does not have any mandatory safety standards governing the sunscreen industry. In fact, a recent study by Environmental Working Group (EWG; investigated 1,106 name brand sunscreens and found that 85 percent of products offer inadequate sun protection or contain ingredients with significant safety concerns.

Several chemical agents, primarily parabens, pthathalates and oxybenzone, have been linked to cancer, reproductive abnormalities and endocrine problems. For these reasons, physical agents are considered safer than chemical ones, especially for children.

That said, recently organizations such as Friends of the Earth Australia, The Royal Society in the UK and several Canadian organizations have been voicing concerns over, and calling for comprehensive studies of, the use of nano-sized particles of zinc and titanium oxide. Many sunblocks utilize zinc oxide and titanium oxide in "nano" form, as this causes the sunblock to leave less residue (think of lifeguards' thick coating of zinc oxide on their noses). There have been some studies done on nanoparticles in Canada and the EU with varying results. EWG reviewed the studies and concluded that, while there is a need for continued investigation, for now the use of sunblocks containing nano-sized particles outweighs the risks of either forgoing sunscreen or of using a sunscreen containing known harmful ingredients. However, they do recommend against using powder or spray-on sunblocks, as nanoparticles may be absorbed more readily through the lungs than through the skin.

Wee Ones Under the Sun Protecting infants, toddlers, children and teens from sun damage is of critical importance because several severe sunburns before age 18 doubles the risk of melanoma later in life. Also, starting healthy sun habits early encourages a lifetime of taking precautions in the sun.

Infants should either be kept out of the sun entirely or covered with tightly woven, non-white cotton clothing as well as a hat while in the sunshine. All sunscreens should be avoided for infants under six months of age. Protective swim wear for younger children is always a good idea. And don't forget to apply (or have your child self-apply) sunscreen before school and before outside play.

Thinking Outside the Bottle Protection from sun damage should not begin and end with sunscreen. Experts recommend wearing a wide-brimmed hat, sitting under an umbrella, wearing sunglasses that provide both UVA and UVB protection and, ideally, avoiding the sun during peak sunshine hours (10am-4pm). Sunbathing, as an activity, is definitely not recommended.

Go out and have fun in the sun, but just make sure you buy wisely, wear a protective clothing and remember to reapply sunscreen every two hours and after swimming.