Over 80% of sunscreen performed below their labelled efficacy (2020)

Why does it not list the brands? The article is both informative and useless simultaneously

Avoid (from other 3 articles/studies): Neutrogena, Banana Boat, Bondi Sands, Cancer Council, Aldi, Nivea, Estée Lauder, iPSA, Anessa, Shiseido, Curél, Sofina, Laneige, Dermacept, Bio-Essence, Fancl (Japan), Purito (Korea)

[1] https://news.ycombinator.com/item?id=45145624

[2] https://labmuffin.com/purito-sunscreen-and-all-about-spf-tes...

[3] https://www.abc.net.au/news/2025-07-04/questions-over-lab-th...

Seems like it's not that simple. The CHOICE study[0] suggest that some brands do have some good "models" of sunscreen, but some are bad. It's also possible that there's a process issue at the manufacturers, and the quality of different lots can vary:

> Ultra Violette announced it was removing the Lean Screen product from shelves. Across eight different tests, the sunscreen returned SPF data of 4, 10, 21, 26, 33, 60, 61, and 64.

[0] https://www.choice.com.au/health-and-body/beauty-and-persona...

> The CHOICE study[0] suggest that some brands do have some good "models" of sunscreen, but some are bad.

For reference, the results were:

   Ultra Violette Lean Screen SPF 50+ Mattifying Zinc Skinscreen   4
                              Cancer Council Ultra Sunscreen 50+  24
                   Neutrogena Sheer Zinc Dry-Touch Lotion SPF 50  24
                                                  Aldi Ombra 50+  26
                    Bondi Sands SPF 50+ Zinc Mineral Body Lotion  26
                      Cancer Council Everyday Value Sunscreen 50  27
                      Woolworths Sunscreen Everyday Tube SPF 50+  27
                  Banana Boat Baby Zinc Sunscreen Lotion SPF 50+  28
                    Bondi Sands SPF 50+ Fragrance Free Sunscreen  32
                              Cancer Council Kids Clear Zinc 50+  33
                      Banana Boat Sport Sunscreen Lotion SPF 50+  35
             Invisible Zinc Face + Body Mineral Sunscreen SPF 50  38
           Nivea Sun Protect and Moisture Lock SPF 50+ Sunscreen  40
               Sun Bum Premium Moisturising Sunscreen Lotion 50+  40
  Nivea Sun Kids Ultra Protect and Play Sunscreen Lotion SPF 50+  41
                              Coles SPF 50+ Sunscreen Ultra Tube  43
        Mecca Cosmetica To Save Body SPF 50+ Hydrating Sunscreen  51
                          Cancer Council Kids Sunscreen SPF 50+   52
                       Neutrogena Ultra Sheer Body Lotion SPF 50  56
                 La Roche-Posay Anthelios Wet Skin Sunscreen 50+  72

> It's also possible that there's a process issue at the manufacturers, and the quality of different lots can vary

If you read the article, that variable test result was provided by Ultra Violette themselves. Choice tested it three times with three different independent testers and got results of 4,5,5. It's possible Ultra Violette is just trying to muddy the waters here.

I feel like this is mostly bullshit because high SPFs are mostly bullshit. A promised SPF of 50 and a tested value of 40 means it blocks 97.5% instead of 98% of the sun.

Anything higher than 30 or even 15 isn't really meaningful. At that point how long it lasts and how resistant it is to water is far more important.

SPF 50 blocks 25% more UVB than SPF 40 does. Measuring it as percentages makes it non-linear in a way that most people find confusing. Imagine we had one sun cream that blocked 99.9% and another that blocked 99.5%. Sounds like nothing; only an 0.4p difference, but is actually 5 times as effective.

You're right about how long it lasts also being an important factor. UV-A protection is also another very important factor. But as someone with pale skin even by Scottish standards, the difference between SPF 40 and SPF 50 around noon is significant, even through I consistently re-apply every hour. I won't get burnt, but I'll end up with more sun damage - and that lasts until late autumn.

>99.9% and another that blocked 99.5%. Sounds like nothing; only an 0.4p difference, but is actually 5 times as effective.

I disagree. Both effectively stop all damage to the skin. It's like having 10 inches of steel armor for bullet proofing instead of 1. A bullet isn't getting through either so they are equally effective.

But sunscreen doesn't stop all damage to skin. I spent weekdays working inside on a computer, then sometimes spent summer weekends outside in the sun. I get sunburned easily, sometimes in like 10 minutes of direct sun. You wouldn't try to deny a light sunburn isn't skin damage? SPF 50 suncreen, blocking 98% of sun, extends the 10 minutes by 50x to 8.3 hours, but that is still not that great. I can still exceed that in two days. And I don't see why having light skin and wanting to spend the weekend outside would be unusual. Blocking 99% of UV and doubling the time over 98% would help quite a bit.