DISCLAIMER: This article is provided as commentary and discussion, not direct medical advice. Before making any medical decision, consult with your medical provider.
In the Northern Hemisphere, the weather is getting warmer, days are getting longer, and more time is collectively being spent outside. Although sun exposure precautions should be considered year round, it is important to be especially mindful of these precautions during warmer months and when more time is being spent outside.
Although proper sun safety has many different components, one key component of sun safety is to wear sunscreen when feasible.
Many questions can arise after someone inquires about which sunscreen product may be the best. Like all other over-the-counter products, this answer can vary depending on the person. At a minimum, it is important to consider sun protection factor (SPF), broad-spectrum protection levels, water repellant capabilities, product formulations, and active ingredients.
The AAD recommends choosing a sunscreen product that is SPF 30 or higher, has broad spectrum protection (protects against both UVA and UVB), and is water resistant. However, SPF 15 or higher is also considered acceptable as that is the minimum count recommended by the Centers for Disease Control and Prevention (CDC).
Oils, lotions, creams, gels, butters, pastes, ointments, and sticks are the sunscreen product formulations that are considered “GRASE” (generally recognized as safe and effective) by the United States Food and Drug Administration (FDA).
Active ingredient(s) should also be evaluated prior to using a sunscreen product. This article entails a discussion of active ingredients to consider when deciding which sunscreen product to purchase and utilize.
Alongside the CDC and FDA, the American Academy of Dermatology (AAD) is one of the premier organizations to reference when considering skin health at-large – this includes knowing which sunscreen product(s) to consider. This article discusses sunscreen active ingredients that are currently recommended for use by the AAD and FDA.
The ingredients detailed below are all considered to be acceptable. However, prior to using any product, it is important to ask your dermatologist, primary care provider, pharmacist, or other healthcare provider about which sunscreen product may be most appropriate for you.
Zinc Oxide
Zinc oxide is a naturally-occurring mineral that is commonly used in topical sunscreen products and a wide variety of other cosmetics. The FDA regulates the safety and effectiveness of zinc oxide in addition to other ingredients used in sunscreen products.
Considered to be a physical sunscreen, zinc oxide is often the single active ingredient in many sunscreen products. It also can be combined with titanium dioxide, which is mentioned below. Physical sunscreen products are occasionally called sunblock or mineral sunscreen products.
Zinc oxide is recognized by the FDA as being GRASE.
According to the AAD, “physical sunscreens work like a shield, sitting on the surface of your skin and deflecting the sun’s rays… opt for this [type of] sunscreen if you have sensitive skin.”
Image 1: Categorizing and Assessing Sunscreen Ingredients
In Image 1, zinc oxide is depicted in the bottom row of the table. Of all the listed sunscreen ingredients, zinc oxide is currently thought to be the most protective active ingredient against both UVA and UVB rays. Titanium dioxide is considered to be the next most protective ingredient against both UVA and UVB rays.
In terms of strengths, a sunscreen product’s zinc oxide concentration can go up to 25%, according to the FDA. Acceptable zinc oxide concentrations typically range from 5% to 25%. If zinc oxide is combined with titanium dioxide in a product, the zinc oxide percentage is usually much lower than 25%. If a product contains more than 25% zinc oxide, it should not be used.
All of the ingredients listed in Image 1 will be further discussed below.
Example zinc oxide products (not all inclusive)
Titanium Dioxide
Titanium dioxide is a naturally-occurring element that can be used as a topical sunscreen. It is also used in many other cosmetic products. The FDA regulates the safety and effectiveness of titanium dioxide in addition to other ingredients used in sunscreens.
Titanium dioxide, similarly to zinc oxide, is recognized by the FDA as being GRASE.
Also considered to be a physical sunscreen, titanium dioxide is commonly combined with zinc oxide in many sunscreen products.
Image 2: Visual Representation of Sunscreen Protection Levels
Image 2 further drives home the message of Image 1. Zinc oxide is noted to provide the most protection against UVA1, UVA2, and UVB rays, but titanium dioxide also offers helpful protection.
In terms of strengths, a sunscreen product’s titanium dioxide concentration can go up to 25%, according to the FDA. However, as titanium dioxide is typically used in combination with zinc oxide, this percentage is typically much lower. If a product contains more than 25% titanium dioxide, it should not be used.
In regard to both zinc oxide and titanium dioxide, physical sunscreen products generally can be used for most skin types, including sensitive skin. After physical sunscreen products are applied, they are active immediately.
Physical sunscreen products typically need to be applied multiple times per day. At a minimum, the CDC recommends reapplying sunscreen after being exposed to the sun for more than two hours and/or after swimming, sweating, or toweling off. However, as many products are on the market, be sure to look at package directions for specific recommendations on how often a particular sunscreen product should be applied.
Physical sunscreen summary: both zinc oxide and titanium dioxide are go-to active ingredients to consider using. There is typically not a preference between choosing a stand-alone zinc oxide sunscreen product versus choosing a zinc oxide/titanium dioxide combination sunscreen product. They are generally thought to be equally safe and effective.
Example zinc oxide/titanium dioxide combination products:
- CeraVe Hydrating Sunscreen Face Sheer
- Cetaphil Sheer Mineral Sunscreen Lotion for Face & Body
- Murad City Skin® Age Defense Broad Spectrum
Avobenzone, Ensulizole, Homosalate, Octisalate, Octocrylene, Octinoxate, and Oxybenzone
Considered to be chemical sunscreens rather than physical sunscreens, avobenzone, ensulizole, homosalate, octisalate, octocrylene, octinoxate, and oxybenzone are active ingredients that can be used in combination with one another in many chemical sunscreen products. These active ingredients are commonly used in the United States.
According to the AAD, “chemical sunscreens work like a sponge, absorbing the sun’s rays… these formulations tend to be easier to rub into the skin without leaving a white residue [compared to physical sunscreens].”
To understand the difference between chemical and physical sunscreens, reference Image 3 below.
Image 3: Comparing Chemical and Mineral Sunscreen Ingredients
After applying any chemical sunscreen, it is important to wait 15 to 30 minutes prior to exposure to sunlight. As these sunscreens absorb into the skin, there is a small lag time before they start working.
Chemical sunscreens are generally able to be used for most skin types as well, but they are more likely than physical sunscreens to potentially cause skin irritation. Chemical sunscreens are considered to be more water and sweat resistant to physical sunscreens, however, and may be more preferable for people with active lifestyles.
Regardless of which sunscreen type is chosen, typically only one sunscreen should be applied at a time. A physical sunscreen should not be worn at the same time as a chemical sunscreen.
Chemical sunscreen products, like physical sunscreen products, typically need to be applied multiple times per day. At a minimum, the CDC generally recommends reapplying sunscreen if someone is exposed to the sun more than two hours and/or after swimming, sweating, or toweling off. However, as many products are on the market, be sure to look at package directions for a specific recommendation on how often a particular sunscreen product should be applied.
Separately and importantly, there are 12 specific active ingredients in chemical sunscreen products that are still being studied and evaluated by the FDA. The active ingredients still being fully evaluated for potential GRASE status by the FDA are avobenzone, cinoxate, dioxybenzone, ensulizole, homosalate, meradimate, octinoxate, octisalate, oxybenzone, octocrylene, padimate O, and sulisobenzone. Of these, cinoxate, dioxybenzone, meradimate, padimate O, and sulisobenzone are not commonly used in the United States.
Nevertheless, chemical sunscreens products are still considered acceptable to use according to the AAD and FDA. But, as of now, the only sunscreen products that are listed as being GRASE are zinc oxide and titanium dioxide.
In general, chemical sunscreens are an alternative option to physical sunscreens. Although current guidance generally favors the use of physical sunscreen products over chemical sunscreen products, both types can be used.
Example chemical sunscreen products:
- Hawaiian Tropic Silk Hydration Weightless Lotion
- La Roche-Posay Anthelios Clear Skin Dry Touch Sunscreen
- SkinCeuticals Light Moisture UV Defense
Key Takeaways
Both physical and chemical sunscreen products are available for use in the United States. Although the physical sunscreen active ingredients of zinc oxide and titanium dioxide may be generally favored, chemical sunscreen products are still a viable option to utilize.
If anything, it’s helpful to also know which sunscreen product types should be avoided. Although the list below is not all-inclusive, it is a helpful list to start with.
- Avoid sunscreen-insect repellent combination products. These products are not considered to be safe and effective.
- Para-aminobenzoic acid (PABA) and trolamine salicylate are not considered to be safe and effective active ingredients for sunscreen products.
- Oral sunscreen products should not be utilized. Only use topical sunscreens that are applied to the skin.
- Any sunscreens that have a SPF lower than 15-30 should not be used as these products likely will be ineffective.
- Avoid sunscreens that are labeled “waterproof” or “sweat proof” as these claims cannot be validated. Claims such as “water resistant” are acceptable.
- Any sunscreen products that are expired should be discarded.
With all of this in mind, regulation advancements are forthcoming for the world of sunscreen products. Read on for a summary of a proposed FDA regulation to help make all sunscreen products even more safe and effective.
Prior to using any product, it is important to ask your dermatologist, primary care provider, pharmacist, or other healthcare provider about which sunscreen product may be appropriate for you – regardless of type.
References:
- Sunscreen FAQs. American Academy of Dermatology (AAD). Last updated 2019. Accessed 19 April 2021. Accessible via: https://www.aad.org/public/everyday-care/sun-protection/sunscreen-patients/sunscreen-faqs
- Sun Safety. Centers for Disease Control and Prevention (CDC). Last updated 9 April 2020. Accessed 19 April 2021. Accessible via: https://www.cdc.gov/cancer/skin/basic_info/sun-safety.htm
- FDA advances new proposed regulation to make sure that sunscreens are safe and effective. United States Food and Drug Administration (FDA). Published 21 February 2019. Accessed 19 April 2021. Accessible via: https://www.fda.gov/news-events/press-announcements/fda-advances-new-proposed-regulation-make-sure-sunscreens-are-safe-and-effective#:~:text=The%20U.S.%20Food%20and%20Drug,products%20in%20the%20United%20States.&text=Among%20its%20provisions%2C%20the%20proposal
- Sunscreen: The Burning Facts. Environmental Protection Agency (EPA). Last updated September 2006. Accessed 20 April 2020. Accessible via: https://www.epa.gov/sites/production/files/documents/sunscreen.pdf
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