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

(www.consumer.org.hk)
230 points mgh2 | 22 comments | 06 Sep 25 19:57 UTC | HN request time: 0.001s | source | bottom
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Insanity ◴[06 Sep 25 21:22 UTC] No.45152959[source]▶
Why does it not list the brands? The article is both informative and useless simultaneously
replies(1): >>45153021 #
mgh2 ◴[06 Sep 25 21:28 UTC] No.45153021[source]▶
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...

replies(7): >>45153085 #>>45153094 #>>45153355 #>>45153485 #>>45153680 #>>45153747 #>>45153897 #
1. kelnos ◴[06 Sep 25 21:36 UTC] No.45153085[source]▶
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...

replies(2): >>45153195 #>>45153271 #
2. evolve2k ◴[06 Sep 25 21:50 UTC] No.45153195[source]▶
Unhelpful, I’d say avoid these brands until they get their house in order; this is a major scandal and the market should be punishing those who clearly did not cover their basic duty of care when selling products that claimed to offer specific SPF sun protection.

While true there could be a process issue, it’s very clearly incumbent on manufacturers to correctly prepare and test their product before sending it on to consumers and representing that the product has properties that it may indeed not have.

Negligence law covers this well.

It’s why you don’t get poisoned too often when you buy food products not prepared in your own home.

replies(1): >>45153340 #
3. theteapot ◴[06 Sep 25 22:01 UTC] No.45153271[source]▶
> 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.

replies(2): >>45153343 #>>45153627 #
4. summarity ◴[06 Sep 25 22:10 UTC] No.45153340[source]▶
Exactly, especially since some brands initially pushed back only to then recall products or fire their labs. Lies all the way to the bottom

https://www.bbc.com/news/articles/c4gzl41rpdqo

5. treis ◴[06 Sep 25 22:10 UTC] No.45153343[source]▶
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.

replies(5): >>45153487 #>>45153618 #>>45153877 #>>45153927 #>>45154911 #
6. theteapot ◴[06 Sep 25 22:29 UTC] No.45153487{3}[source]▶
SPF isn't bullshit, it just measure one specific thing, not everything. AFAIK most sunscreens also list expected hours of protection and whether they are water resistant or not.
7. XorNot ◴[06 Sep 25 22:49 UTC] No.45153618{3}[source]▶
The point is you sell a product, it better be what it claims to be.

I didn't buy SPF30, I bought SPF50. When I made that choice, I expect at least SPF50.

But you are also dismissing a 25% difference in total transmitted UV - and that's before degradation in the field due to usage and practical concerns, which is why we want SPF50 in the first place.

replies(1): >>45153693 #
8. SilverElfin ◴[06 Sep 25 22:50 UTC] No.45153627[source]▶
Is this saying the Neutrogena and La Roche did better than stated?
replies(2): >>45153778 #>>45154536 #
9. ◴[06 Sep 25 22:59 UTC] No.45153693{4}[source]▶
10. cjensen ◴[06 Sep 25 23:14 UTC] No.45153778{3}[source]▶
Yes. The original article[1] is clear about that. However only for one of the two Neutrogena sunscreens.

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

11. gblargg ◴[06 Sep 25 23:35 UTC] No.45153877{3}[source]▶
I had to look it up. SPF is a reciprocal value 1/SPF=amount of sun that gets through. So 1/50 allows 2% of UV through, and the difference between say SPF 2 and 3 is enormous but 49 and 50 tiny.
12. cameronh90 ◴[06 Sep 25 23:44 UTC] No.45153927{3}[source]▶
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.

replies(3): >>45154430 #>>45155567 #>>45158516 #
13. treis ◴[07 Sep 25 01:17 UTC] No.45154430{4}[source]▶
>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.

replies(2): >>45154915 #>>45154917 #
14. loeg ◴[07 Sep 25 01:32 UTC] No.45154536{3}[source]▶
Better and worse, for Neutrogena.

  Neutrogena Sheer Zinc Dry-Touch Lotion SPF 50  24
  Neutrogena Ultra Sheer Body Lotion SPF 50      56
15. miladyincontrol ◴[07 Sep 25 02:39 UTC] No.45154911{3}[source]▶
Aside from what others have said, it does matter because few people apply the proper amount. If you're applying only 1/3 the "proper" amount of a 60 SPF product you still at least get 20 SPF of protection as it scales rather linearly.

And as someone paler than most makeup brands go, for many of us it absolutely does make a difference even when using the proper amount.

I ride or die LRP uvmune 400, few protect as well as it does.

16. istjohn ◴[07 Sep 25 02:40 UTC] No.45154915{5}[source]▶
Your metaphor is not at all apt. No bullet is going through ten inches of steel. Some UV radiation will penetrate the strongest sunscreen.
17. aero_code ◴[07 Sep 25 02:40 UTC] No.45154917{5}[source]▶
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.
replies(1): >>45155174 #
18. treis ◴[07 Sep 25 03:35 UTC] No.45155174{6}[source]▶
That isn't how sunscreen works. If you put SPF 50 on and spend 8 hours in the sun you're coming back a lobster.

Say you burn in 5 minutes. SPF 50 means you burn in 250 minutes. But it's more like 100% protection for 245 minutes and then 0% for the last 5. It's not a steady cooking at 2.5% intensity.

replies(1): >>45158159 #
19. s1artibartfast ◴[07 Sep 25 05:09 UTC] No.45155567{4}[source]▶
No, it seems clear that it is 0.4% more effective. It all depends on what you use as your base case hypothetical.
20. rcxdude ◴[07 Sep 25 13:53 UTC] No.45158159{7}[source]▶
Got any source for that? Everything I can find (and the intuitive explanation of it) points to the opposite: SPF is how much of the UV blocks, not at all how long the sunscreen stays on your skin (which varies wildly with what you're doing).
replies(1): >>45159042 #
21. actuallyalys ◴[07 Sep 25 14:36 UTC] No.45158516{4}[source]▶
It seems situational. Someone with your skin at noon absolutely benefits from a higher SPF. Someone with even slightly darker skin [0] going out a few hours before sunset might still want to wear sunscreen, especially if they’re going to be in direct sun the whole time, but a high SPF doesn’t seem very critical.

That being said, I am not a dermatologist, and it’s easy to underapply sunscreen so erring on the side of higher SPFs probably makes sense.

[0]: Note that even people with a lot of melanin still need sunscreen: https://www.pbs.org/newshour/amp/health/why-its-important-ev...

22. treis ◴[07 Sep 25 15:28 UTC] No.45159042{8}[source]▶
https://cdnmedia.eurofins.com/apac/media/609921/spf-iso-prot...

That's my entire point. The way they generate SPF measures how much of the sun it blocks in the lab shortly after it's applied. That one blocks 97.5% and another 98% is meaningless for the real world.