Sunscreens: An Easy Guide to Understanding the Label!

Anita Arora, MD
May 27, 2020
Sunscreens: An Easy Guide to Understanding the Label!

There is always quite a bit of press regarding sunscreens and what is safe and what is not, and here are many types of sunscreens available. With so many choices, many people focus on the higher number SPF when choosing a product. However, there is much more than just SPF number when it comes to selecting the “best” sunscreen for you and your family. Here are important things to consider when choosing a sunscreen:

What sunscreen do I need and when do I need to use it?
Everyone needs a sunscreen that is broad-spectrum (protects against UVA and UVB rays), has sun protection factor (SPF) 30 or higher, and is water resistant. You should use sunscreen every day, even on cloudy days; up to 80% of the sun’s harmful UV rays can penetrate your skin on days that are not considered sunny. One caveat is that parents of babies younger than 6 months should avoid exposing them to direct sunlight and keep them in the shade as much as possible. This is recommended by the American Academy of Dermatology, and thus sunscreen is not usually necessary for this age group.

How much sunscreen do I need to use, and how often do I reapply it?
The standard rule is that you should use two milligrams of sunscreen per square centimeter of skin. This means applying the equivalent of a shot glass (2 tablespoons) of sunscreen to the exposed areas of the face and body. Always apply sunscreen to dry skin 15 minutes before going outdoors, and do not forget to protect your lips as well. There are lip balms that are zinc-based and contain sunscreen with an SPF 30 or higher. Always reapply every 2 hours.

Is a higher number SPF better than a lower-number one?
SPF, or sun protection factor, correlates to how much protection you will receive. For instance, if you normally get a sunburn in 10 minutes, an SPF of 15 extends that by 15 times. With that being said, a SPF higher than 30 does not correlate to protecting you significantly better. An SPF of 30 blocks 97 percent of the sun’s rays and indicates the amount of protection a sunscreen offers against UVB, which is the UV radiation that causes sunburn.

UVA versus UVB rays? What is the difference?
UVA rays have also been called the ‘aging rays’, while UVB rays are the ‘sun burning rays’. In other words, UVA penetrates the skin, causing wrinkles and other skin damage, while UVB causes sunburns. Scientists used to report that only damage with UVB leads to skin cancer, but they now suspect UVA also has a role in skin cancer development. Protection from both UVA and UVB is necessary, and some chemical sunscreens do not provide broad-spectrum defense against both UVA and UVB.

Zinc oxide is the safest and best source of natural broad-spectrum sun protection—it is the ingredient most often used in sunscreens for children and babies. It is also a physical blocker, so it works right away once you apply it to your skin (versus a chemical based sunscreen). There are sunscreens available now that allow the zinc to be ‘micronized’ so it does not appear white on the skin, and they are oil free and non-comedogenic (does not block pores). These sunscreens are best for sensitive skin.


Sunscreen products are regulated by the U.S. Food and Drug Administration (FDA). The FDA has several safety and effectiveness regulations in place that govern the manufacturing and marketing of all sunscreen products. Everyone needs sunscreen, regardless of age, gender or race. If you are concerned about vitamin D production, one only needs about 10 minutes of daily unprotected sun exposure to get your daily dose of vitamin D. Lastly, the type of sunscreen that you choose is a personal choice (gels, sprays, sticks, creams). As long as they are broad spectrum and applied properly, any of them are suitable for daily and extended use.

Anita Arora, MD

Anita Arora, MD

Dr. Anita Arora Gill received her medical degree from Louisiana State University Health Sciences Center in New Orleans, which is linked to the world-famous Charity Hospital. Later she moved to Texas where she obtained her dermatology training at the prestigious Texas Medical Center at University of Texas at Houston and MD Anderson Cancer Center. Her special interests in her field include skin cancer treatment and prevention, acne, psoriasis, and cosmetic dermatology. Dr. Gill is board-certified by the American Board of Dermatology. Professional memberships include the American Academy of Dermatology, Women’s Dermatological Society, and the Texas Dermatological Society. Dr. Anita Arora Gill chose Dermatology, because, as she put it: “I love it! It has never felt like work to me.” Her philosophy of treating her patients is even more so. All she really cares about is you – and your overall health and well-being. In fact, she says, “My practice focuses on the comprehensive, quality care of each and every person who comes to me.” In her free time, Dr. Gill loves spending time with her husband, Dr. Paul Gill, a plastic surgeon in the Woodlands, Texas, and her 2 young daughters. She enjoys traveling, a good book and a great restaurant.

Follow Anita on Facebook @gilldermatology.

Need help choosing the right products or services for your journey?

Check out the products for TTC through parenthood in the Babies After 35 Amazon shop, online courses and other services that come "Dr. Clark-approved"!

Check out my favorite things