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Is sunscreen the new margarine? (2019)
- SilverElfin 3mo agoIt’s great that people are finally talking about this. It should have been obvious that sun exposure without sunscreen is needed to some extent. If you’re blocking the UV all the time, then how could you possibly be getting the minimum UV exposure that you do need. But people have become absolutely obsessed with sun protection.
- flyingshelf 3mo agoI don't know of anyone using sunscreen from the moment they wake up until they go to sleep. Guaranteed that even the best user will still receive a healthy amount of UV even if they refresh every few hours. As far as I'm concerned sunscreen is a 10am-5pm endeavor, not needed before or after
- Zenbit_UX 3mo agoWorth noting here for any readers new to UV guidelines that the above rule isn’t necessarily helpful for you. I’m currently traveling in an area that is 8:30am-4:30pm and live in an area that’s 10-6 pm in the summer and shifts throughout the year. The actual rule is derived from your location’s safe UV index zones, which is found out by determining what local time the UV Index <= 2. Above 2, wear some amount of protection.
- sevenseacat 3mo agoThat's basically sun up to sun down, here. It's been completely grey, overcast, and raining here all day and the UV index sat between 3 and 5.
- Zenbit_UX 3mo agoYa, the relationship between UV and sunlight is strange and unintuitive. For that reason I use a UV widget on my lock screen. I find that being exposed to the value (e.g. 4) while being able to see the suns effect (e.g. cloudy) gives me a better feel for conditions.
- flyingshelf 3mo agoThe worst sunburn I ever got was on a boat while overcast. I don't trust them clouds no more.
- plorkyeran 3mo agoClouds block a decent amount of UV on average, but it’s much less consistent than you might expect. 9/10 you might be completely fine with no sunscreen and then get a horrible sunburn the tenth, with no apparent visual distinction between them.
- rcxdude 3mo agoSunscreen isn't a 100% block, though. In fact it's advertised by what proportion of the UV it blocks. And in general it's far more common to have too much sun exposure than too little, and in the areas where people have too little, it's not exactly the norm to wear sunscreen every time you step outside.
- deleted 3mo ago[deleted]
- erelong 3mo agotl;dr you probably should get a few minutes of sunlight daily on your unexposed skin without sunscreen for the "health gains" (you can also wear clothes to block sun instead of sunscreen so you don't necessarily need sunscreen at all)
- deleted 3mo ago[deleted]
- maleldil 3mo agoYou still need it at least on your face and hands. A hat won't completely protect against UV, and you're probably not going to wear gloves in the summer.
- dntrkv 3mo agoSo everything in moderation? Cool, glad my philosophy still applies.
- TacticalCoder 3mo agoExtreme tension leads to breakage. Something something in buddhism about not trying to put too much tension in a bow or it'll break. Also known as the middle way. Moderation is a great philosophy.
- echelon_musk 3mo ago> something in buddhism about not trying to put too much tension in a bow or it'll break Perhaps you are referencing AN 6.55 Sona Sutta. https://www.accesstoinsight.org/tipitaka/an/an06/an06.055.than.html https://www.accesstoinsight.org/tipitaka/an/an06/an06.055.th...
- halffullbrain 3mo agoModeration is good, just don't overdo it...
- jrflowers 3mo agoNo. It is terrible on noodles. Every brand.
- Jblx2 3mo agoYeah, but it is better than margarine?
- danparsonson 3mo agoI can't believe it's not better.
- Zenbit_UX 3mo agoThe article seems to be a meta analysis of a bunch of conflicting research to support a narrative that we don’t really know shit. And fair, we don’t. But a couple of things we do know that weren’t covered - egregiously so - is that aging is UV damage. Sometimes called photoaging, wrinkles, sun spots, discoloration, fine lines, grey hair, all of that shit that you associate with someone visibly looking old is sun damage. So the picture that the article paints of some pasty nerds in offices shielding themselves from all UV and thus: they might as well be smoking… it doesn’t even touch on why people might be doing this. Both kurgezadt and veritasium did some really great videos on photoaging and it’s worth checking out if this is new information to you.
- JR1427 3mo agoI've not heard that grey hair is sun damage. Do you have any sources for that?
- Zenbit_UX 3mo agoThere’s plenty, though please evaluate the veracity of their claims for yourself, I’m not a scientist nor do I excel at parsing scientific articles. Here’s one I’ve come across after a few minutes which references many others https://www.sciencedirect.com/science/article/abs/pii/S1011134415003206?via%3Dihub https://www.sciencedirect.com/science/article/abs/pii/S10111...
- JR1427 3mo agoAfter a quick skim, that article seems to be talking about something other than typical age-related greying. More photobleaching.
- Zenbit_UX 3mo agoFrom the conclusions: > Sun radiation affects hair properties as color, luster, mechanical resistance, the content of proteins and others. TLDR Yes it impacts color. Further reading can be found in the 75 studies that can be found in the references section.
- sevenseacat 3mo agoComing from the skin cancer capital of the world (Australia) - no, no it is not
- jhbadger 3mo agoYeah, lack of Vitamin D may or may not be a problem (well, obviously in extreme cases it leads to rickets, but that's rare). But skin cancer unquestionably is a problem, and not infrequently a deadly one. Pick your battles.
- amanaplanacanal 3mo agoVery infrequently. Total death rate per year in the US is something like 900 per 100,000 adults, of which less than 3 are from skin cancer. Heart disease, stroke, other cancers, accidents, are all much bigger.
- kulahan 3mo agoAustralia is kind of an exception. You’ve got a super outdoor culture, a bunch of fair-skinned people, thin ozone, and very clear skies.
- kirrent 3mo agoThe title is inadvertently correct only because modern margarine is healthier than alternatives such as butter.
- picofarad 3mo agoSeed oil is healthier than milk fat? Going to need some framing definitions, here...
- kirrent 3mo agoI had to look up the concept of a framing definition so I might have gotten these wrong but I would equivalently state: 1. Modern margarine is healthier than butter. 2. Seed oils are generally healthier than animal fats. 3. PUFAs are healthier than saturated fats. 4. In this case the industrial processed spread is healthier than the more natural less-processed spread.
- jml7c5 3mo ago(2019)
- Cockbrand 3mo agoA bit unclear - it says > Weller’s largest study yet is due to be published later in 2019 But in the header, it also says > Updated May 31, 2024 I'd still love to know whether there has been further research in the meantime.
- dang 3mo agoAnd https://web.archive.org/web/20260000000000*/https://www.outsideonline.com/health/wellness/sunscreen-sun-exposure-skin-cancer-science/ https://web.archive.org/web/20260000000000*/https://www.outs... seems to suggest 2021. I guess we'll put that above, although we had 2019 in the 2022 thread (https://news.ycombinator.com/item?id=48715020 https://news.ycombinator.com/item?id=48715020) :)
- jml7c5 3mo agoIt was published early 2019, maybe late 2018. Searching for the title of the article ("Is sunscreen the new margarine?") makes it easy to pinpoint: there is a open letter responding to the article, dated January 15, 2019. https://www.asds.net/Portals/0/PDF/LetterToTheEditor-Outside_1.15.19.pdf https://www.asds.net/Portals/0/PDF/LetterToTheEditor-Outside...
- dang 3mo agoOk, let's go with 2019!
- _visgean 3mo agohttps://www.sciencedirect.com/science/article/pii/S1353829224001564?via%3Dihub https://www.sciencedirect.com/science/article/pii/S135382922... this is better source on the underlying study
- poulpy123 3mo ago[flagged]
- d4ng 3mo agoTFA says that many sunscreens block radiation causing sunburn, rather than radiation causing cancer.
- abracadaniel 3mo agoThe US only just approved a new one for broad spectrum UV protection. That distinction has largely been a US only issue.
- dang 3mo ago"Please respond to the strongest plausible interpretation of what someone says, not a weaker one that's easier to criticize. Assume good faith." "Don't be snarky." https://news.ycombinator.com/newsguidelines.html https://news.ycombinator.com/newsguidelines.html
- dang 3mo agoRelated: Current guidelines for sun exposure are unhealthy and unscientific – research (2019) - https://news.ycombinator.com/item?id=31471416 https://news.ycombinator.com/item?id=31471416 - May 2022 (335 comments)
- Cider9986 3mo agoDo we really have to reapply every 2 hours?
- layman51 3mo agoI have heard that some Asian or European sunscreens have some UV blockers that are much more stable than the ones that are mainly used in sunscreens available in the USA. So if you’re using one of these, the need to reapply isn’t as much of a concern. The only thing is that they aren’t FDA approved. Some examples I have heard of are “ethylhexyl triazone”, “diethylamino hydroxybenzoyl hexyl benzoate”, and “bemotrizinol”. EDIT: The last chemical on my list was actually approved by the FDA this month (June 2026).
- DuckConference 3mo agoYes. Most modern sunscreens are photostable, but even if you aren't going in water or sweating, just moving around (and thus scrunching and un-scrunching your skin on a micro level over and over again) is enough to mess up the sunscreen layer you put on your skin.
- kixiQu 3mo agohttps://hidefromit.substack.com/p/there-is-no-evidence-you-should-reapply https://hidefromit.substack.com/p/there-is-no-evidence-you-s... <-- somebody claims that's kind of a ghost citation effect. (for what it's worth, I'm quite pro-sunscreen, it just seems to keep working over time better than this advice implies)
- picofarad 3mo agoThis is one of those things that will start a fight at a beach party so I'm just goongtto forget the two tenuous studies the FDA used to stand up the guidelines.
- toasty228 3mo agoIt depends what sunscreen you use: mineral vs chemical font behave the same, on how much you used, on what you're doing. Chemical ones go bad with exposure to sun, mineral ones not as much, but either way they can both be rubbed off the skin
- layman51 3mo agoDoes anyone know whether UVA or UVB is more conducive to producing vitamin D naturally? A quick search shows me that it is mainly UVB that's responsible for that, but unfortunately, this is what gets blocked out by glass windows and sunscreen. On the other hand, UVA is what causes early aging. So this is just an unfortunate situation because I don't think there's a way of just getting UVB into you in a safe way.
- krupan 3mo agoThe article explains that it is much safer than not getting UVB. Nothing in this universe is completely safe, but the evidence is that getting UVB is bar far safer than not getting it
- jodrellblank 3mo agoUVB makes it. UBA denatures it[1], which I thought was how we avoid overdose levels building up in the skin when outside, but can't find a source for that. Suggested as a reason why fair-skinned indoor workers are getting more melanomas, (ref glass blocking UVB and passing UVA): https://www.sciencedirect.com/science/article/abs/pii/S0306987708005999 https://www.sciencedirect.com/science/article/abs/pii/S03069...
- picofarad 3mo agoOffhand, what was the overdose level? Because 150ng/ml (adjust if I messed units up) isnt an overdose and most people are around ~50 unless they supplement (I mean people outside the 25th parallel.) I think even approaching 300ng/ml is possibly safe as long as you're accounting for the calcium. I aim to be around 105ng/ml.
- jodrellblank 3mo agoI have no idea what the numbers were, I took it in as a system idea: more time in sunlight, more UVB, more Vitamin D. Then UVA breaks it down slowly, so more builds up in the skin, more is being broken down, acting as a control-feedback brake on the increase. > "unless they supplement" I have seen plenty of claims that low levels of Vitamin D correlate with many diseases and overall mortality, but that supplementing Vitamin D hasn't been proven to help. Is there any consensus on that? > "as long as you're accounting for the calcium". Vitamin D helps bodies absorb calcium but has concerns about high blood levels of calcium. Taking Vitamin K2 as well helps redirect that calcium to the bones instead of the artery walls, apparently. But high levels of Vitamin A could also be causing loss of bone calcium into the blood: """in the industrialized world excess of vitamin A has been suggested to be a risk factor for secondary osteoporosis and enhanced susceptibility to fractures. Preclinical studies unequivocally have shown that increased amounts of vitamin A cause decreased cortical bone mass and weaker bones due to enhanced periosteal bone resorption. Initial clinical studies demonstrated a negative association between intake of vitamin A, as well as serum levels of vitamin A, and bone mass and fracture susceptibility. In some studies, these observations have been confirmed, but in other studies no such associations have been observed. One meta-analysis found that both low and high serum levels of vitamin A were associated with increased relative risk of hip fractures.""" - https://pmc.ncbi.nlm.nih.gov/articles/PMC11070503/ https://pmc.ncbi.nlm.nih.gov/articles/PMC11070503/ which could be a confounding factor with Vitamin A and its precursors in so many animal and plant foods and fortified into more, and in daily multivitamin supplements, skin creams, moisturisers and such.
- jondcallahan 3mo agoI made a small little web app calculator for myself and my family to figure out how long we could stay outside without needing sunscreen based on current UV and skin type. I use it daily in the summer and a couple thousand people use it every month also. You can check it out at https://sunburntimer.com https://sunburntimer.com. It's also free and open source software, github link in footer.
- Arubis 3mo agoDenver, CO, USA resident here -- this looks _super_ useful and I'm likely to start using it heavily. Our weather here is usually very outside-encouraging (if getting hotter over the years) and our UV is _ridiculous_; I see the index hit 11 and 12 with some regularity. Thanks for the link!
- mreid 3mo agolaughs in Australian https://www.bom.gov.au/climate/maps/averages/uv-index/?period=jan https://www.bom.gov.au/climate/maps/averages/uv-index/?perio...
- wil421 3mo agoThe map isn’t too far off for July[1] considering how far Australia is from the Equator[2]. My area is similar to Sydney in your map. For Denver it’s the elevation that’s exposing them to more UV rays. [1]https://www.epa.gov/sunsafety/sun-safety-monthly-average-uv-index-2006-2023#tab-7 https://www.epa.gov/sunsafety/sun-safety-monthly-average-uv-... [2]https://www.reddit.com/r/MapPorn/comments/cd1t54/relative_latitude_of_australia_compared_to_north/ https://www.reddit.com/r/MapPorn/comments/cd1t54/relative_la...
- Arubis 3mo agoYep, this—we aren’t as close to the equator, but there’s less atmosphere to filter UV. Not so much in terms of beach days, of course, so sunburns here tend to be less than full-body. All that said: a daily mean of 13-14 is past what we’d see here—and yeah that is some serious burning.
- ericmcer 3mo agoI think this all stems from Baby boomers controlling the narrative. Baby boomers had an insane relationship with the sun. Getting crispy brown tan, using tanning oils, using that metal collar to blast sun directly into their face, and frequenting tanning beds were viewed as totally normal and healthy things. Big surprise they all got skin cancer. Then they swung the pendulum all the way back and now preach 24/7 sunscreen and never letting the sun touch you.
- robertjpayne 3mo agoThe article doesn't make really controlled findings. There's an argument to be made that the increase to diseases isn't purely lack of vitamin D but lack of exercise. Our ancestors got lots of Vit D but they also got lots of exercise while absorbing the sun. I still don't think it's going to be wise to go out and just bake in the high UV of early afternoons but rather it's important to go outside early to mid morning or late afternoon and absorb some sun without copious amounts of sunblock.
- krupan 3mo agoWow, it feels like nobody read the article. Findings: - high blood pressure leads to a lot of deaths - people that spend more time in the sun have lower blood pressure - skin cancer is caused by sun exposure, but it kills far, far less people than high blood pressure - people that spend more time in the sun have a lower rate of dying from skin cancer than people who spend less time in the sun! Summary: more sun exposure makes you less likely to die on at least two fronts! It's really very simple. You skin adapts to sunlight and doesn't burn if you increase your exposure gradually, and then you get some amazing benefits from it!
- IcyWindows 3mo agoWhat I got from this is if we mandate the hospitals open their rooms to the sun, the new correlation will cause people to avoid the sunlight because "it leads to more deaths"
- XorNot 3mo agoI read the article and it conjectures a bunch of stuff but fails to prove it or link relevant studies. So consider then: we just did a round of "gloves are contaminating basically all micro plastics research" - it might be worthwhile to be slightly skeptical of a suspiciously anti-sunscreen adjacent narrative (coz "sunscreen might be bad for you" is in the article too). And we should absolutely be suspicious of narratives which have the benefit of confirming someone should do what they already wanted to do: nobody likes putting on sunscreen. And how strange the conclusion is mostly "you don't need sunscreen" versus "use a lower SPF".
- jona-f 3mo agoI agree, that article is suspicious. One thing, what if you are not at risk of heart disease? I'm not fat, fairly active, have a low blood pressure and use sunscreen to slow down skin aging. Lots of health advice does not apply to me, cause it is meant for the overweight population. There are the biggest possible health gains to have, so statistically everything that makes people less fat is going to "be healthy for humans". When standing up from a longer squat I tend to blacken out a bit (never fully fainted) and this gets much worse with sun exposure. So I can totally confirm the underlying scientific finding of this article. Sun exposure does seem to lower blood pressure, but the rest is all conjecture and lacks differentiation.
- deleted 3mo ago[deleted]
- andai 3mo ago>These rebels argue that what made the people with high vitamin D levels so healthy was not the vitamin itself. That was just a marker. Their vitamin D levels were high because they were getting plenty of exposure to the thing that was really responsible for their good health—that big orange ball shining down from above. Yeah, it's not just UV. Infrared light has beneficial effects on deep tissue, including the brain. There's no way to get that from a pill.
- pazimzadeh 3mo agoSunlight does way more than just produce vitamin D: Photo-neuro-immuno-endocrinology: How the ultraviolet radiation regulates the body, brain, and immune system https://www.pnas.org/doi/10.1073/pnas.2308374121 https://www.pnas.org/doi/10.1073/pnas.2308374121
- stevage 3mo ago> Homo sapiens have been around for 200,000 years. Until the industrial revolution, we lived outside. How did we get through the Neolithic Era without sunscreen? Actually, perfectly well. What’s counterintuitive is that dermatologists run around saying, ‘Don’t go outside, you might die.’” At least in Australia a big difference is that there is a hole in the ozone layer that stone age people did not have. Sun exposure is much more harmful now.
- toasty228 3mo ago> How did we get through the Neolithic Era without sunscreen? By reproducing at 15 years old long before cancer is a problem? Skin cancer was probably at the very bottom of causes of death back then, by a fat margin. They also didn't have tooth paste, tooth brush, soap, antibiotics, vaccines, so go ahead and live like a caveman... I'm 100% positive it'll have a negative impact on your lifespan
- sunnydeedee 3mo agoSince biological evolutionary forces have forever been fighting the sun are our bodies MORE or LESS suited to dealing with UV damage vs oxybenzone damage? Since oxybenzone can intercalate DNA rungs under extremely high local concentrations (forcing some molecules into cavities), or by photo-oxidation converting to radical cation, or in the presence of ethanol which lowers DNA hydration layers and can widen the inter-pair base gaps, then is it causing MORE DNA damage or LESS DNA damage than the Sun's ultraviolet radiation which can contribute to cancer under real world conditions?
- toasty228 3mo agoEither way it doesn't matter, use mineral sunscreen. Of course if you use bottom tier sunscreen formulated in the 60s you're asking for troubles
- Melatonic 3mo agoSo.... get a small reasonable amount of sun and use sunscreen whenever you are getting more ?