June 4, 2015 Emmy Graber Spotlight

Sunscreen, Explained: What You Need to Know

Here at MDC, we would love to think that we have all the answers for you. However, there are certain issues that require the insight of a pro. Today we asked Boston-based dermatologist Emmy Graber to help us get to the bottom of a major skincare mystery: the difference between chemical and physical sunscreen.

Whether you are a sun-worshipper or have an occasional day in the sun here and there, you should wear sunscreen and know what type is best for you. There are different ingredients in sunscreens that can protect you from the sun’s harmful rays.  Most sunscreens contain a combination of both physical sunscreen ingredients and chemical sunscreen ingredients.  What’s the difference in these ingredients and how can this affect what type of sunscreen you buy? 

Sunscreen Guide

What’s Physical Sunscreen?

Physical sunscreens consist of ingredients called zinc oxide or titanium dioxide.  They serve as a barrier on the skin, blocking the sunlight from hitting it.  Physical sunscreens (like La Roche Posay Anthelios SPF 50) actually go above and beyond and reflect the sunlight right off your body. This solution may seem like a no brainer when it comes to protecting oneself, but many avoid physical sunscreens because they tend to leave a white residue on the skin that is difficult to wash off.

RELATED: How to Practice Safe Sun

What’s Chemical Sunscreen?

Chemical sunscreens can’t actually block the sunlight the way physical sunscreens can.  Instead, they filter sunlight and reduce the amount of ultraviolet rays that pass through to the skin.  Depending on the ingredients, some chemical formulas protect against ultraviolet B light while some guard against ultraviolet A. Chemical sunscreens (like Kiehl’s Super Fluid UV Defense SPF 50) are the more preferred options for sunblock as they are colorless and do not leave white streaks all over your skin. The downside is that some people can be allergic to the chemical ingredients and the solution can sting if it gets into the eyes.

Which Sunscreen Type is Best for Me?

The ingredients found in physical sunscreen block the most sunlight, so if you tend to be outdoors a lot, have fair/sensitive skin or have a history of melanoma or another type of skin cancer, look for sunscreens containing zinc oxide or titanium dioxide. If you want a sunblock that will be absorbed into the skin and has an invisible finish, opt for a formula containing only chemical ingredients.  No matter what you choose, remember these two golden rules: look for an SPF of 15 or higher and make sure the formula is “broad spectrum.”

Enough about sunscreen! Let’s move on to more skincare tips and tricks!

Photo: iStock



    About the Author: Dr. Graber is a Boston-based dermatologist specializing in acne, acne scars and cosmetic dermatology.