Summer Skincare with Ellen Marmur, MD

Lanby Team

SPF PSA: With summer in full swing, a reminder to follow proper sunscreen protocol. Dr. Ellen Marmur, Board Certified Dermatologist and founder of MMSkincare, takes on our most frequently asked summer skincare questions. Check out our conversation below.

Reading a sunscreen ingredient list: what do we want to see on there?

You want to ensure that you’re using a sunscreen with enough wide spectrum UV protection. Some good ingredients to look for in your sunscreen are Octocrylene, Titanium Dioxide, Zinc Oxide, Octisalate and Avobenzone. I would recommend avoiding sunscreens with oxybenzone, as it can cause skin irritation. Look for the words "reef safe" to be sure the run off of the sunscreen is clean for ocean life.

How often should we be replacing our sunscreen? Can we use our leftover bottles from last summer?

Sunscreens have expiration dates, so as long as the expiration dates are taken into consideration, you can use a leftover sunscreen from last summer. But if you left your sunscreen out in the heat, you probably need to replace it, because excess heat will change the formulation.

How does the use of sunscreen impact Vitamin D absorption?

There are many misconceptions about sunscreen causing vitamin D deficiency, but this is not scientifically proven. In fact, studies have shown that you can use sunscreen daily and still maintain healthy vitamin D levels. Vitamin D is not absorbed from the sun; it is converted by UV rays from its inactive form to its active form. Sunscreen filters UV but doesn't block it all, so you are still activating your own vitamin D.

What's your take on SPF mineral powders? Any lightweight sunscreen brands you recommend for sensitive skin?

SPF mineral powders are great for oil-prone skin since other types of sunscreen can leave a greasy layer on the skin. First, I would recommend using Sasha Suncare Tinted Mineral Sunscreen — it’s fragrance free, which makes it non irritating and safe for the skin.  If you want to use a powder, we recommend using it over sunscreen, or even over makeup.

And because we can always use the reminder, how often should we be reapplying sunscreen? How does that change if we're using water resistant sunscreen?

It is important to reapply sunscreen every 2 hours even if using a water resistant sunscreen. When interacting with water and drying yourself with a towel, you’re removing the sunscreen and must reapply to guarantee proper protection. Water resistant sunscreen tells you on its label whether it offers 40 or 80 minutes of protection. That means you may need to reapply as soon as 40 minutes later.

Even with all of this information and so many great options for sun protection, skin cancers are still on the rise affecting 1 in every 5 Americans. Dr. Marmur’s office started a philanthropy with the American Academy of Dermatology to prevent and protect people from it called Skin Cancer, Take a Hike! If you or someone you know cares deeply about skin cancer prevention, please consider becoming involved.