Check out this answer from Consensus:
Sunscreens with SPF values higher than 30 do offer superior protection against sunburn and UV-induced erythema, especially when applied in real-world amounts. They also provide long-term photoprotective benefits, potentially reducing the risk of skin cancer and photoaging. However, users should be mindful of their sun exposure behavior, as higher SPF sunscreens may encourage prolonged sun exposure. Overall, investing in higher SPF sunscreens can be worthwhile, particularly for individuals who are frequently exposed to intense sunlight or have a higher risk of skin damage.
The debate over the efficacy of sunscreens with higher Sun Protection Factors (SPF) has been ongoing. While some argue that higher SPF values provide significantly better protection, others believe that the benefits are marginal and may encourage prolonged sun exposure. This article aims to explore whether sunscreens with SPF values higher than 30 are indeed worth the investment by examining recent research findings.
Efficacy of High-SPF Sunscreens
Several studies have demonstrated that sunscreens with higher SPF values offer superior protection against sunburn and UV-induced erythema compared to those with lower SPF values. For instance, a randomized, double-blind study comparing SPF 100+ and SPF 50+ sunscreens found that SPF 100+ was significantly more effective in protecting against sunburn in actual use conditions. The study reported that 55.3% of participants were more sunburned on the SPF 50+ protected side, while only 5% were more sunburned on the SPF 100+ protected side1. Another study conducted over five consecutive days of sunlight exposure also concluded that SPF 100+ provided better protection than SPF 50+, with significantly less erythema observed on the SPF 100+ side5.
Consumer Application and Real-World Usage
One of the critical factors affecting the efficacy of sunscreens is the amount applied by consumers. Research indicates that consumers often apply sunscreen at densities much lower than the recommended 2 mg/cm², resulting in significantly reduced protection. A study measuring the actual SPF values of sunscreens applied at various densities found that high-SPF sunscreens (SPF 70 and above) provided substantial protection even when applied at lower densities typical of consumer use. For example, SPF 70 and SPF 100 sunscreens applied at 0.5 mg/cm² provided actual SPF values of 19 and 27, respectively4. This suggests that higher SPF sunscreens can compensate for inadequate application amounts, offering better protection in real-world scenarios.
Behavioral Implications of High-SPF Sunscreen Use
While higher SPF sunscreens offer better protection, they may also influence sun exposure behavior. A study examining the sun-exposure duration of participants using SPF 10 and SPF 30 sunscreens found that those using SPF 30 had longer cumulative sun exposure and daily sunbathing durations. However, there was no significant difference in sunburn experience between the two groups2 3. This indicates that higher SPF sunscreens may encourage prolonged sun exposure, potentially offsetting some of their protective benefits.
Photoprotective Potential and Long-Term Benefits
Higher SPF sunscreens not only prevent sunburn but also offer long-term photoprotective benefits. A study comparing SPF 15 and SPF 30 sunscreens found that SPF 30 provided a significantly superior degree of photoprotection, almost preventing sunburn cell induction. Since sunburn cells are markers of UV-induced DNA damage, higher SPF sunscreens may offer advantages in preventing skin cancer and long-term actinic damage7. Additionally, modern sunscreens with micronized metal oxides like zinc oxide and titanium dioxide provide efficient UV attenuation, further enhancing their protective capabilities9.
Are sunscreen’s higher than SPF 30 worth it?
Brian Diffey has answered Near Certain
An expert from Newcastle University in Photobiology
There is commonly-held, but fallacious, belief that applying sunscreen with an SPF higher than 30, e.g. SPF 50+, confers little additional benefit to using just a SPF30 sunscreen. The basis of the argument is that SPF30 means that 1-1/30 = 96.6% of solar UV is absorbed by the sunscreen and that an SPF60 sunscreen, for example, means that 1-1/60 = 98.3% is absorbed – apparently a difference so small that it is of little benefit.
But what is important to skin health is not what is absorbed by the sunscreen but how much UV reaches the skin. So in the case of an SPF30 product the skin exposure relative to unprotected skin for a given time in the sun is 1/30 = 3.3%, whereas for an SPF60 product the relative exposure is 1/60 = 1.7%. In other words, twice as much UV reaches the skin when an SPF30 product is applied than when the same quantity of SPF60 is applied.
And we shouldn’t forget that most people who apply sunscreen do so at an average thickness that is typically around one half of that used by manufacturers during the laboratory testing. In other words, if you apply a sunscreen labelled SPF30, you are probably getting closer to 10-15 times protection, and not the 30-fold protection you might expect. So another benefit of applying a high SPF product is to compensate for under-application.
Are sunscreen’s higher than SPF 30 worth it?
Stephan Bielfeldt has answered Likely
An expert from proDERM Institute for Applied Dermatological Research in Dermatology, Photobiology
Products with SPF > 30 are truly meaningful. The main reason is, that people usually apply less than 1 mg/cm², but SPF is based on an application dose of 2 mg/cm². According to our studies on low dose application, an SPF of 50 drops to about 25 when applying only 1 mg/cm². https://www.karger.com/Article/Abstract/96173
Are sunscreen’s higher than SPF 30 worth it?
S Seité has answered Extremely Unlikely
An expert from La Roche-Posay Dermatological Laboratories in Photobiology
Key points to take into account :
- SPF values follow a linear scale when determined in standardized conditions (2 mg/cm²) that means SPF 60 is the double of SPF30 , the erythema is reached after 60 Minimal erythemal dose (MED) versus 30 MEDs
- 2 mg/cm² are used for standardization and results reproducibility however consumers used around 1/3 of this amount; studies have demonstrated that in most of the cases SPF value decreases in a linear relationship so SPF 30 is about 10 in realistic conditions ; sometimes the decrease ca be exponential depending on the quality of the film of the product on the skin, it is the case if the film is not uniform
- With a SPF10 , in a zenithal sun radiation condition, in summer, a skin phototype 1 can have an erythema in about 2.5 hours;
- many studies have demonstrated that even before the erythema skin damage can occur, the minimal dose inducing sun damage has been found at 0.5 MED; in the case of a phototype 1 , in the condition described above , it is equivalent to less than 1.5 hours
- Recommendation to reapply every 2 hours is not sufficient in this case and the solution is to offer SPF > 30 such as SPF 50 or 50+
- Another aspect is the UVA protection; today the best regulatory request is UVA protection factor at least 1/3 of the SPF. That means for a SPF30 , UVAPF10. Again , taking into account the lower quantity of product applied by the consumers (1/3 of 2mg/cm²), the UVAPF value can decrease to UVAPF around 3
- Many studies have shown UVA damage can occur in less than 1 hour under the sun (single or repetitive exposures), so it is important to ensure a higher UVA protection through products higher SPF values.