How To Read Sunscreen Labels

Taking a walk down the sunscreen aisle can be bit overwhelming to say the least. There are tons of different brands and types to sort through and reading all the claims on the labels can definitely be confusing. The good news is while much of the beauty industry is unregulated, sunscreen is considered an over-the-counter drug ingredient and is regulated by the FDA. Sunscreens are required to undergo FDA approved standardized testing to prove the formula is effective and do what they say they are going to do. (i.e. protect against sunburn.) So what do all these terms and claims mean on a sunscreen bottle?

UVA Rays

UVA stands for ultra violet aging rays which contribute to premature aging, wrinkles, sun spots/freckles and can pass through window glass.

UVb Rays

UVB stands for ultra violet burning rays and are responsible for a sunburn and are blocked by window glass.

Active sunscreen ingredients

These ingredients are how you can determine if a sunscreen is a chemical or physical sunscreen. Occasionally, you will see a combination of both types of active ingredients within one formula.

Chemical (organic) sunscreen

These types of sunscreens absorb into the skin and absorb UVA and UVB rays. Here is the list of common sunscreen active ingredients:

  • Oxybenzone

  • Avobenzone

  • Octisalate

  • Homosalate

  • Octocrylene

  • Octinoxate

Physical/Mineral (inorganic) sunscreen

These types of sunscreens sit on the surface of the skin and deflect UVA and UVB rays. (They also absorb a small amount of UVB rays.) Here is the list of common sunscreen active ingredients:

  • Zinc Oxide

  • Titanium Dioxide

sunscreen lingo

Inactive Sunscreen ingredients

These are the other ingredients in the sunscreen formula that help to emulsify, moisturize, preserve or smooth out the sunscreen on the skin. While we are used to seeing ingredient decks listed from highest to lowest concentration, the rules for sunscreen are different. They can be listed in alphabetic order or highest to lowest concentration and it’s ultimately up to the brand.

Broad Spectrum sunscreen

This is a type of sunscreen that protects your skin from both UVA and UVB rays.

SPF number

This stands for sun protection factor and is the measure of how long a person can stay in the sun before UVB rays start to burn the skin.

Let’s say you are outside with no sunscreen and your skin starts to get red within 10 minutes. And SPF 30 will allow you to stay in the sun 30 times longer without getting burned. It is important to keep in mind sweating and swimming for reapplication along with the fact that sunscreens start to lose effectiveness over time so reapplying every two hours is the best practice.

SPF 15 = 93% of the sun’s UVB rays
SPF 30 = 97% of the sun’s UVB rays

No sunscreen can filter out 100% of the sun’s rays, even higher SPF numbers!

Sunscreen vs. Sunblock

Originally, sunblock was a term used to describe physically blocking the sun’s rays with mineral or physical sunscreen ingredients. While sunscreen was used as the term to filter the sun’s burning rays with chemical sunscreen ingredients. Over the years both words have been used interchangeably regardless how the sunscreen actually works. So in 2011 the FDA stopped allowing the word “sunblock” because it could lead people to think they were receiving better protection than they actually were.

Waterproof Sunscreen

Surprisingly, there really is no such thing. Think about it, sweat and water break down sunscreen from our skin so how can it truly be “waterproof?” It will eventually wash off. The FDA no longer allows this claim on sunscreen.

Water + sweat-resistant sunscreen

This is how long a sunscreen will stay on wet skin and requires testing to prove and claim this on a label.

Water/Sweat-Resistant = 40 minutes
Very Water/Sweat-Resistant = 80 minutes

Sport Sunscreen

This FDA has NOT defined this term and is basically a marketing term for water/sweat resistant.

Baby + Kid Sunscreens

To the surprise to many, the FDA has not defined these terms and still fall under the same regulations and testing as regular “adult” sunscreens. However, they are often considered to be “gentler” formulas made with zinc oxide or titanium dioxide versus chemical sunscreen actives. They often don’t contain certain potentially irritating ingredients like fragrance. (Make sure to read the ingredients!)

Reef-safe or reef-friendly

These terms are used to describe sunscreens that are do not contain oxybenzone and octinoxate which are two common UV-blocking chemical sunscreen ingredients that studies have shown can cause coral bleaching. The fact of the matter is no sunscreen has been proven to be completely safe for marine life and it’s also not regulated by the FDA or any other regulating organization. At this point, more research and studies need to be performed to fully understand the impact of sunscreens and marine life. (This is why I stick to physical sunscreens!)

Expiration dates

These dates are actually pretty important because there is no assurance the sunscreen will remain safe and fully effective past the expiration date stamped on the bottle. Sunscreen formulas are stability tested to last one to three years. The active sunscreen ingredients can oxidize and degrade over time losing its effectiveness.

A word on DIY + oils as sunscreen

By now we’ve all heard coconut oil is a “natural sunscreen” or that you can whip up a sunscreen in your kitchen. HARD NO. This is simply unsafe and untrue.

Homemade sunscreens don’t undergo any testing to prove they work. Plus, taking in consideration the other inactive ingredients and how they react with active ingredients like how it’s mixed to provide an even, protective coverage on the skin or the pH levels and how the formula will maintain the effectiveness in the bottle over time.

Oils such as coconut oil or carrot seed are rumored to provide natural sun protection. The fact of the matter is plant oils do not absorb or reflect UVA or UVB rays at the correct wavelengths, period.

I wrote an in-depth article on this topic for Healthline.com if you would like to learn more.