My family and I had the pleasure of traveling to Florida for an impromptu vacation a few weeks ago. Our pasty, white complexions were not ready to hit the sandy, white beaches without a quick trip to the local pharmacy to purchase some sunscreen. As I was standing there in the sunscreen aisle, I felt my head begin to swirl at the dizzying array of options available. The variety of formulations was endless. One can choose lotions, sprays, foams, chemical, physical, sport, water resistant, acne prone, kid safe, baby formula and most thought provoking…reef-friendly? Are these all the same? Which one is best? With one out of every five adults developing skin cancer in their lifetime, people are more aware of the sun and its potential to cause skin cancer. Sun safety is often complicated by the important health benefits of outdoor exercise.
There are two types of sunscreen: chemical and physical. Chemical sunscreens absorb into the skin and then absorb the sun’s UV rays, converting them to heat and releasing them from the body. The active ingredients often include avobenzone, octinoxate, homosalate and octisalate. These are carbon-based compounds that are absorbed into the skin and won’t leave chalky, white streaks running down your body when you begin to sweat. The benefit of using a chemical sunscreen is that it is more sweat resistant and water resistant than physical sunscreen formulations. People who engage in prolonged water sports or exercise outside in the sun are better protected by chemical sunscreens. These sunscreens often come in spray formulations, which make it easier to apply to the tricky but important spots of the body like the back, scalp, and hairline.
The downside of chemical sunscreens is that they can exacerbate acne and sensitive skin conditions and require proper timing of application. Patients who have sensitive skin may develop rashes from chemical sunscreen and mistakenly believe that they are allergic to sunscreen. In addition, teenagers or adults who struggle with acne often refuse to use any kind of sunscreen on their face for fear of breakouts. Furthermore, chemical sunscreens can take up to twenty minutes to become effective after being applied to the skin, which unfortunately requires you to time the application process correctly. Two chemicals in this type of sunscreen, oxybenzone and octinoxate, have been linked to coral reef harm and have been banned in some states. Due to this ban, most chemical sunscreens now clearly state on the front of the bottle “Oxybenzone and Octinoxate-free.”
Recently a study in JAMA suggested that with maximal application four common ingredients in chemical sunscreen can absorb into the bloodstream. This has been a very hot debate in the news lately in regard to what these chemicals can do to our bodies with long-term exposure. The FDA explained that the purpose of this small, preliminary study is not to dissuade people from using sunscreen but to spark additional research on these ingredients. The four chemicals tested in the study were avobenzone, oxybenzone, octocrylene and ecamsule. People who find this new data worrisome may choose to switch to a physical sunblock.
Physical or mineral sunblocks use either zinc oxide or titanium dioxide as a main ingredient. The minerals sit on top of the skin instead of being absorbed into the skin. They work by reflecting the UV rays off of the skin. The upside of using one of these products is that they go to work immediately after application. In addition, they are not absorbed into the pores so they do not exacerbate acne. They are best for people with heat-activated conditions like melasma or rosacea. These products also come in organic and vegan formulations. The downside of physical sunscreens is that they may come off too easily while swimming or sweating. In addition, you need to use a larger amount of this product and apply it more frequently. Some of the formulations are labelled as “Nano-size minerals,” which prevent the chalky appearance of most physical sunscreens. The problem is that this formulation can also be absorbed by marine life and cause harm. I recommend that people who swim in the ocean avoid sunscreen brands that list “Nano-size” in the ingredients list.
Both chemical and physical sunscreens need to be applied to dry skin every two hours. Applying sunscreen to wet skin will only dilute the product, and it will not be effective. You need a minimum of SPF 30 to block out 97% of the sun’s harmful rays. If you are swimming outside for a long period of time or sweating heavily, both sunscreens will only be effective for approximately 80 minutes. There is no such thing as a waterproof sunscreen. Both chemical and physical sunscreens need to be rubbed in completely, regardless of whether the formulation is a spray, cream or lotion. Most adults require a minimum of one ounce of chemical or physical sunscreen (in lotion form), which is approximately the size of a shot glass.
It is important to make sunscreen application part of your daily routine. I recommend that patients put a bottle of sunscreen by their toothbrush so that they get into the habit of applying sunscreen before they go outside for the day. Don’t forget to apply it to your ears, nose, eyelids, tops of hands, and scalp. As far as which sunscreen is best, I recommend having a variety of sunscreen formulations on hand. All of my family members have different skin concerns, which makes it difficult to buy just one kind. I always have a non-Nano physical sunscreen for those of us that suffer from sensitive skin, acne, rosacea or melasma. In contrast, during heavy sweat sessions or prolonged water-based activities, it is good to have an Oxybenzone-free, Octinoxate-free, chemical sunscreen that won’t be easily wiped off with a towel.
By Elizabeth Walsh, PA-C
Elizabeth Walsh, PA-C, is a physician assistant who treats skincare issues in adult and child patients at the Margaret Ravits, M.D. and Associates Dermatology practice in River Edge, New Jersey. To learn more about her or contact her, please visit