How Much Sunscreen to Apply

You know how important it is to wear sunscreen—it's your best defense against skin cancer, painful sunburns, and premature skin aging.[1] But did you know that just applying any sunscreen might not give you the full protection you need? The amount you apply, the SPF level, and the type of sunscreen all significantly impact the protection your sunscreen provides. Interestingly, most people don't use sunscreen correctly, either applying too little or not reapplying throughout the day.[2]

The Recommended Amount of Sunscreen to Apply

To achieve the full benefit of the SPF listed on your sunscreen label, it's essential to apply an adequate amount. The FDA determines the effectiveness of sunscreen based on tests using 2 milligrams per square centimeter of skin.[3] For the average adult, this translates into:

• 1 teaspoon of sunscreen for the face and neck
• 1 teaspoon per arm
• 2 teaspoons for the torso (covering both the front and back)
• 2 teaspoons per leg

While it may be hard to picture these amounts, you likely need more sunscreen than you think.

The Difference Between SPF 50, 30, and 15

Generally, a higher SPF value indicates a higher level of protection against sun exposure. However, there are diminishing returns when it comes to SPF:

• SPF 15 filters out 93% of UVB rays[5]
• SPF 30 filters out 96.7% of UVB rays[5]
• SPF 50 filters out 98% of UVB rays[5]

Achieving higher SPF ratings typically requires formulations with higher concentrations of active ingredients like zinc oxide, which can leave a more noticeable white cast on the skin.

Many individuals reduce the amount of sunscreen they apply to avoid a noticeable white cast. This leads to reduced protection from their sunscreen. Ironically, some users gain more benefits and protections from lower SPFs due to adequate application. For this reason, we've opted for an SPF sweet spot of SPF 30 to maximize your protection while maintaining cosmetic desirability. Both OneSkin’s sunscreens, OS-01 BODY SPF and OS-01 FACE SPF, are powered by our proprietary OS-01 Senescence Blocking Peptide™, protecting your skin from UV damage while targeting aging at the source.[6,7]

Applying Sunscreen Properly

When applying sunscreen, the effectiveness relies on quality, quantity, and timing. Ensure that you’re using a product that works for your skin, rather than against it.

• Prevent breakouts: If you’re worried about using too much sunscreen, fearing it might cause breakouts, select lightweight, non-comedogenic options that won't clog pores. As always, perform a patch test with new products, including safe and non-comedogenic ones, such as OneSkin's line of products.
• Prevent white cast: White cast is a common issue in mineral sunscreens and can be more pronounced on darker skin tones. By matching your skin tone with a tinted option (such as the three tinted options of OS-01 FACE SPF), you can provide your skin with the protection it needs without compromising its natural glow.
• Water resistant: Use water-resistant sunscreens certified to last 40 to 80 minutes if you plan to swim or exercise, as most conventional sunscreens are not waterproof, especially mineral-based ones. If you are swimming, make sure to reapply after you get out of the water, as towel drying removes sunscreen.
• PRO TIP: If you’re looking for a water-resistant sunscreen for your face, try OS-01 BODY SPF on your face. (Making sure to perform a patch test first, as always.) Though OS-01 FACE SPF was specifically formulated to benefit the thinner skin on your face, both OS-01 BODY SPF and OS-01 FACE SPF are non-comedogenic and gentle on facial skin.

Tips for Applying Sunscreen Effectively

Timing matters a lot when it comes to sunscreen application.

• After skincare: Applying sunscreen to your face should be the last step in your skincare routine, but applied before makeup.
• Wait 15 minutes: It can take up to 15 minutes for sunscreen to become effective. So wait before you expose your skin to the sun.[5]
• Layer up: For mineral sunscreens, which are more prone to leaving a white cast, especially on darker skin tones, start in layers. Begin by applying a layer to one area, move to another area to let it dry, and then return to the first area for an additional layer if necessary. This method ensures an even and adequate application while minimizing visible residue.[8]
• Reapply: The most common mistake many make is not reapplying sunscreen throughout the day. Applying sunscreen at the beginning of the day won't suffice, as most mineral and chemical sunscreens lose their effectiveness after two hours. In fact, most damage that your skin accumulates is during the hours after your sunscreen has worn off. If you plan to be outside for long periods, reapply sunscreen every 2 hours or as needed, especially between 10 AM and 4 PM when UV radiation is strongest.[9]

To ensure you’re getting the best in skincare and sun protection, consider exploring OneSkin’s range of products. Unlike other sunscreens, OS-01 FACE SPF and OS-01 BODY SPF offer not just one, but three types of protection, including non-nano zinc oxide to prevent UV aging, powerful antioxidants to combat free radicals, and the OS-01 peptide to target cellular senescence, reducing the visible signs of aging that have already occurred from sun exposure.[6,7] Read more about why our SPF outperforms the rest.

Key Takeaways:

• Adequate application is the key to getting the full benefit of the SPF on your sunscreen label.
• Higher SPF values indicate greater protection against UV rays, but the benefits have diminishing returns. For example, SPF 30 blocks about 96.7% of UVB rays, while SPF 50 blocks about 98%, only a slight increase. Therefore, SPF 30 is often recommended as a balance between effective protection and minimal white cast.
• Most people fail to apply enough sunscreen or don’t reapply it frequently enough. Sunscreen should be reapplied every 80 minutes to 2 hours, especially during peak sunlight hours.
• For mineral sunscreens prone to leaving a white cast, applying in layers allows the sunscreen to dry and settle between applications, reducing visible residue and ensuring more even coverage.
• Sunscreens like the OS-01 BODY SPF and OS-01 FACE SPF offer additional benefits, including our OS-01 peptide, scientifically proven to reduce the visible signs of aging induced by UV exposure.

References

1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6773941/
2. https://pubmed.ncbi.nlm.nih.gov/12374537/
3. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/labeling-and-effectiveness-testing-sunscreen-drug-products-over-counter-human-use-small-entity
4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4577364/
5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3460660/
6. Based on data from clinical studies and/or lab studies conducted on human skin samples, 3D skin models, and skin cells in the OneSkin lab. Explore more at oneskin.co/claims.
7. https://www.nature.com/articles/s41514-023-00109-1
8. https://www.webmd.com/beauty/how-to-find-sunscreens-without-a-white-cast
9. https://pubmed.ncbi.nlm.nih.gov/30273065/