10 ms·
Time to sunburn
- janci5243 5y agoThis might be completely a common knowledge, but I just learned recently that SPF (the number on most sunscreen products) is actually a multiplier of the time you can spend in the sun without any protection So having an SPF of 50 increases a time 50 fold, which really puts things into perspective. Never leave the house around lunchtime without sunscreen.
- jandrese 5y agoAlso remember however that the SPF numbers on most sunscreen are aspirational. They usually require you to apply a much heavier coat than most people think is reasonable and have shorter than you would expect full effectiveness window. As the article discusses it also depends on your skin. If you are a fair ginger then yeah, sunscreen is your life. If you are more swarthy then you can get away with some midday sun.
- outworlder 5y ago> then you can get away with some midday sun No you can't. Or rather, you shouldn't. If you have more melanin you obviously have more protection. But your skin will still get damaged by a midday sun, and it will age faster than normal. This misconception that darker skin does not need protection is really harmful. Maybe that allows you to skip sunscreen for short periods of time, or in early morning, late evening. Not midday, unless "some sun" means just a few minutes.
- jandrese 5y agoMy understanding is that overuse of sunscreen is also considered harmful as it inhibits Vitamin D production. It's one of those areas where striking the right balance is difficult as it is different for everybody. As a result you had conflicting advice from every corner.
- ihumanable 5y agoThis is not correct, https://www.fda.gov/about-fda/center-drug-evaluation-and-research-cder/sun-protection-factor-spf https://www.fda.gov/about-fda/center-drug-evaluation-and-res... <quote> There is a popular misconception that SPF relates to time of solar exposure. For example, many consumers believe that, if they normally get sunburn in one hour, then an SPF 15 sunscreen allows them to stay in the sun 15 hours (i.e., 15 times longer) without getting sunburn. This is not true because SPF is not directly related to time of solar exposure but to amount of solar exposure. Although solar energy amount is related to solar exposure time, there are other factors that impact the amount of solar energy. For example, the intensity of the solar energy impacts the amount. The following exposures may result in the same amount of solar energy: - one hour at 9:00 a.m. - 15 minutes at 1:00 p.m. </quote>
- csours 5y agoIt's correct, but with extra steps required for comparison.
- tgb 5y agoI don't see anything in that article that actually contradicts the definition of SPF. It's basically saying: > It's a common misconception that speed determines how fast you get to your destination, but actually distance also matters. So speed does not reflect time to destination. Instead, speed lets consumers compare the level of relative quickness and that 60mph is quicker than 6mph. Obviously we need to hold other factors constant. It's not a useful point in when talking about speed and I don't see the point in talking about SPF. And it certainly doesn't mean that time to destination is inversely proportional to speed.
- thehappypm 5y agoIf you're standing under a UV light that's constant, I think the SPF === time works. In the real world, where the sun, ya know, rises and sets, this is actually a harmful assumption.
- tgb 5y ago
- taeric 5y agoNeat. Curious how to interpret this when you are tanned some. My understanding is that doesn't change your skin type, but you do build some resistance. That not the case?
- janci5243 5y agoThis article seems to say that getting a base tan helps to get 3-4 SPF, so your time-to-sunburn increases up to 4 times. https://www.health.harvard.edu/blog/problem-tanning-myth-base-tan-2017041211528 https://www.health.harvard.edu/blog/problem-tanning-myth-bas... I would not rely on it overall tough.
- qmmmur 5y agoYou have a base level of resistance determined by your genes. When you get burned you tan and that burn is a function of time spent out in sun multipliednby that base protection. Tanning is our bodies response to the damage done by this as a form of preventing more damage. The damage however is accumulative.
- taeric 5y agoThis makes since sense, but still feels too simplified. I used to spend many hours outside and basically developed a skin type that was easily two types higher than I have normally. When this happened, I found I could definitely do longer without a hat or other sun shades with no negative impact. Fast forward a few years and I'm back to where the first few days mowing the yard will see me get burned. Give it a few weeks and I can go longer without a hat.
- qmmmur 5y agoYou repeatedly damaged your skin to maintain the tan.
- taeric 5y agoI get that. But some damage is different from other damage. Getting callouses is similar to getting blisters. But one is much worse for you. (With the other being somewhat beneficial...) So my question is how bad is it, really? Straw man arguments of folks being ridiculously tanned from tanning beds aside, is there much trustable discussion over mild tans? Edit: Probably better asked in terms of my blister analogy. Is there benefit to getting tanned similar to building up callouses? Or is it purely cosmetic?
- Equiet 5y agoThere's a video which shows how you look like to a UV camera when you put sunscreen on. Also glasses with UV filters: https://www.youtube.com/watch?v=o9BqrSAHbTc https://www.youtube.com/watch?v=o9BqrSAHbTc
- deleted 5y ago[deleted]
- fouronnes3 5y agoMy ultimate dream is a pair of magical glasses with a small knob on it, which when turned adjusts the wavelength you can see from deep radio all the way to high energy gamma. Just imagine seeing the entire spectrum.
- jandrese 5y agoYou want Geordi's VISOR from Star Trek.
- libraryatnight 5y agoThe episode where they hook up his visor so they can display what he sees on screen was always cool to me.
- cwkoss 5y agoI know I do!
- fouronnes3 5y agoYes!!
- throwawaycities 5y agoNot sure the other spectrums of light are intense enough on average for such glasses to work without them also emitting all spectrum of light (essentially a walking radar/lidar/X-ray/etc… machine). For example we of course have these types of “glasses” for infrared which is fine for humans because we give off significant quantities of infrared radiation, but lesser known is we also emit light in the visible spectrum, it’s just not enough intensity for our rods/cones or inversely our rods/cones are not sensitive enough to observe the visible light we emit. Anyway your invention would be cool, even if it just ratcheted up the existing visible light spectrum enough we could see ourselves glowing in the dark…it would give people a new appreciation for Carl Sagan’s quote that we are made of stardust.
- BugsJustFindMe 5y agoGetting GeocoderQuotaExceeded
- cryptoz 5y agoWorth mentioning that UVA and UVB are different, and that there are multiple sunscreen scandals happening right now where UVA protection is insufficient. UVB causes burns and tanning but UVA causes more cancer; and American suncreens especially - but also globally - are not telling the truth about how much protection they offer. You've got to be careful to really apply multiple layers of sunscreen with UVA protection in order to get the skin-cancer-reducing benefits. A thin layer does not do it. Thick layers required, and be warned, you sunscreen label may be lying to you about how much protection it offers.
- pdr94 5y agoThis happened in South Korea, there were 3 brands that needed to pull their products because of this. https://www.nssgclub.com/en/pills/25875/solari-coreani-controversia-purito-klairs https://www.nssgclub.com/en/pills/25875/solari-coreani-contr...
- Johanx64 5y agoHard part is finding sunscreen which isn't cancerous or poisonous itself. 1 in 4 seem to have benzene in it. The sunscreen sitting on my shelf has talc in it. Etc If only I could just buy sunscreen without having to worry about any of this shit.
- clint 5y agoIf you look over that table, its generally the cheap drugstore sunscreens pushed by 2-3 large multinational companies. Buy a higher quality sunscreen (there are multiple reddits for this exact purpose) and you will not get poisoned by benzene and it won't be greasy and smelly.
- rplst8 5y agoYou need to look for sunscreens that say "broad spectrum". That is the approved language in the U.S. for UVA protection. https://time.com/3924609/sunscreen-spf-uva-uvb/ https://time.com/3924609/sunscreen-spf-uva-uvb/
- 5y ago
- okareaman 5y agoIt's even easier at altitude, such as at nice swimming lakes in the mountains.
- ptsd_dalmatian 5y agoThis explains why going for a summer vacation directly from programmers winter dungeon produces painful moments quite quickly.
- ReptileMan 5y agoBars around the beaches usually have good shade and cold beer.
- pmoriarty 5y agoFor those who, like me, started to wonder how using sunscreen affects vitamin D production, here's the conclusion of "The effect of sunscreen on vitamin D: a review": "There is little evidence that sunscreen decreases 25(OH)D concentration when used in real-life settings, suggesting that concerns about vitamin D should not negate skin cancer prevention advice. However, there have been no trials of the high-SPF sunscreens that are now widely recommended. What's already known about this topic? Previous experimental studies suggest that sunscreen can block vitamin D production in the skin but use artificially generated ultraviolet radiation with a spectral output unlike that seen in terrestrial sunlight. Nonsystematic reviews of observational studies suggest that use in real life does not cause vitamin D deficiency. What does this study add? This study systematically reviewed all experimental studies, field trials and observational studies for the first time. While the experimental studies support the theoretical risk that sunscreen use may affect vitamin D, the weight of evidence from field trials and observational studies suggests that the risk is low. We highlight the lack of adequate evidence regarding use of the very high sun protection factor sunscreens that are now recommended and widely used." https://pubmed.ncbi.nlm.nih.gov/30945275/ https://pubmed.ncbi.nlm.nih.gov/30945275/
- 49531 5y agoFortunately Vitamin D supplements are a safe and effective way to get the recommended amount. UV exposure is the most preventable cause of skin cancer[1] and not worth the risk. EDIT Forgot my link: 1. https://www.hhs.gov/sites/default/files/call-to-action-prevent-skin-cancer.pdf https://www.hhs.gov/sites/default/files/call-to-action-preve...
- gojomo 5y agoBut, after 50+ years of rising sunscreen use, there's essentially no data showing more sunscreen use reduces skin cancer. Sunscreen definitely prevents sunburns, and almost certainly delays visible skin aging/weathering. Those may be enough benefits for some people. But the people/populations using more sunscreen are also having more skin cancer. Some theories compatible with these observations are: • While preventing sunburn pain, sunscreen doesn't prevent the actual cancer-causing skin damage - and thus by allowing more time to be spent in the sun, actually worsened skin cancer rates. (This may have especially been a problem for the 1960s-1990s, when it was thought that only sunburn-causing UVB contributed to skin cancer - so sunscreens only blocked UBV. That encouraged increased exposure to the mostly-unblocked UVA, now understood as an equal contributor to skin cancer. More recent sunscreens block UVA as well.) • Known carcinogens commonly used in sunscreens, or present as contaminants, are actually causing increased rates of skin cancer. Anyone whose true worry is skin cancer should use shade & limited times of exposure - not sunscreens. (Ensuring a spaced-repetition of gradually-increasing exposure, to develop a natural tan without ever reaching a peeling burn, is also likely naturally protective against skin cancer.) Further, while endogenous Vitamin D production relies on sun exposure, and low Vitamin D is correlated with health problems, oral Vitamin D supplementation may not replace all the benefits of sun exposure. Generally, large population studies show positive effects of moderate sun exposure on many health outcomes, including overall longevity, heart disease, and non-skin cancers. Meanwhile, Vitamin D supplementation studies have usually not found that such supplementation alone reverses the correlations of many diseases with low Vitamin D. Thus, Vitamin D may not be the only mechanism by which sun's benefits are achieved. So rigorous sun-exposure-minimization, even if it does reduce (often benign or increasingly survivable) skin cancers, may increase overall mortality through higher heart disease & other cancers. (Your HHS report mentions 9,000 skin melanoma deaths per year. There are 650,000 heart-disease deaths and 600,000 other cancer deaths.) Get sun. Use shade, clothing, & timing to ensure it's not so much sun that you peel. Use sunscreen sparingly, only when you can't moderate sun exposure other ways.
- jeremyw 5y agoConsider removing omega-6 seed oils from your diet. Like many others who have tried it, I now have a normal tan response, where in the past I burned in a heartbeat. Note: you do need to wait a few months for the fatty acid composition of your skin to turn over.
- mijoharas 5y agoCould you go into a little more detail on this and/or provide references? This is the first time I'm hearing about a link between omega-6 oils and sunburn.
- simonsarris 5y agoSame: I suspect a good omega 3 ratio greatly reduces skin damage with sun. Anecdotally it's worked for me and my wife when we started eating a lot more eggs/red meat and less O-6 products. We haven't used sunscreen in a few years now because of it. There are some studies that suggest this is true, such as: https://pubmed.ncbi.nlm.nih.gov/7561154/ https://pubmed.ncbi.nlm.nih.gov/7561154/ (note: N = 13) And Oregon State "Essential Fatty Acids and Skin Health" primer, which goes over what's going on in healthy skin. https://lpi.oregonstate.edu/mic/health-disease/skin-health/essential-fatty-acids#functions https://lpi.oregonstate.edu/mic/health-disease/skin-health/e... Their conclusion: > Supplementation with n-3 fatty acids in particular exerts protection from photodamage and photoaging.
- hawski 5y agoBut aren't eggs themselves overall much more an O-6 source than O-3?
- VoiceOfWisdom 5y agoMy family(except for one brother) and I have completely cut all seed oils out for the last year. No longer burn at all, except for the brother that has not. He goes inside looking like a lobster.
- annoyingnoob 5y agoLooks neat, failing on city lookup for me.
- niek_pas 5y agoSame, looks like quota exceeded.
- hprotagonist 5y agoI _hate_ sunscreen. It's unpleasant to wear. I always do, but it's not my favorite part of summer by far. This year i am experimenting with rashguards and big stupid floppy hats.
- ahelwer 5y agoHats are good, as is sun-protective clothing in general. There are a number of companies providing some kind of ultra-thin sun-protective hoodie which is surprisingly comfortable to wear even in hot temperatures. I have a few echo hoodies from outdoor research.
- m-p-3 5y agoThere are sun sleeves which you can wear with your casual clothes too.
- clint 5y agoSome sunscreen is and it's mostly the cheap drugstore junk you see in almost all retail settings. There are plenty of sunscreens out there which are not greasy and don't stink and you won't notice once you apply it.
- silicon2401 5y agoBuy UPF shirts from Patagonia, a relatively environmentally-friendly company. I never go out in the summer without UPF-50 long sleeve shirts, never have an issue with tanning let alone burning, and always feel perfectly comfortable as I don't have to apply or remove as much sunscreen.
- hprotagonist 5y agoalready done, yup!
- mrfusion 5y agoI got a water based one which doesn’t feel bad but then I’m not sure if it stays in when I sweat.
- 5y ago
- kingabzpro 5y agoThis is amazing interective dashboard like notebook.love it
- lettergram 5y agoI almost exclusively refuse to wear sunscreen. The data isn’t exceptionally clear if wearing vs no wearing leads to overall more or less cancer system wide. Further, it definitely reduces vitamin D production and has harmful chemicals when in the water supply and absorbed into your skin. You can wear very lose light cotton clothing, hats and avoid too much direct sun. Further, going out regularly will typically keep a tan (for most). The Amish have notoriously low rates of cancer and don’t use sun block AND work outside all day. I typically try to imitate their methods.
- overcast 5y agoThe Amish are also notoriously covered head to toe in clothing. Obviously if no sun touches you, it's difficult to be affected by it.
- deleted 5y ago[deleted]
- tgb 5y agoThis model doesn't take into account time of day, but many do. But those mostly seem to do so incorrectly, as far as I can tell. They tend to use the measure of "UVA/B incident on a horizontal square meter". However humans are not flat horizontal surfaces - and in fact a lot of my exposed skin is more vertical than horizontal. Therefore I think the correct measure should be "UVA/B incident on a meter-diameter sphere" or similar (where absorption from the atmosphere is the only contributor, not merely foreshortening). I was unable to identify numbers for this at all when I looked into it - does anyone know of a model that does this properly? Or just number of how much UVA/B is impacted by this?
- epiteton 5y agoTry duplicating the project, it should give you access to the code. Also the API returns the current weather/UV index, so the result is always for the current time at the location.
- bradgranath 5y agoWe've destroyed the atmosphere on this planet in so many ways to the point that we should all just be wearing spacesuit all the time.
- JadeNB 5y agoA minor suggestion: the image for the Fitzpatrick skin type labels them "Type 1", "Type 2", etc., but the selector labels them "Type I", "Type II", etc.
- nerbert 5y agoNeat! Wolfram alpha also does it.
- avidiax 5y agoI'd argue that Wolfram Alpha does it better: https://www.wolframalpha.com/input/?i=uv+index+90210 https://www.wolframalpha.com/input/?i=uv+index+90210
- mywittyname 5y agoI think you're API key might be out of requests. I'm getting this error, no matter what location I put in, even though the Location block correctly returns the coordinates for whatever city I put in. Exception Traceback (most recent call last) <ipython-input-5-9b29f394b1fd> in <module> 7 location_response = requests.get(f'https://api.opencagedata.com/geocode/v1/json?key={OPENCAGEDATA_API_KEY}&q={Location}&no_annotations=1&limit=1') 8 if not location_response.ok: ----> 9 raise Exception('Location not found') 10 11 location_json = location_response.json() Exception: Location not found
- Taniwha 5y agoDangerous! does not seem to take the southern hemisphere ozone hole into account
- tantalor 5y agoBug: you can safely sunbath -> you can safely sunbathe sunbath is a noun, sunbathe is a verb
- 11235813213455 5y agoIf people could avoid as much as possible suncreams, that'd be great (using natural protections, clothes, ...), just for their plastic wrapping at least, I know some are said to be environment-safe, but still
- AceJohnny2 5y agoWhere are you that suncream packaging is the most concerning litter?
- 11235813213455 5y agoEarth, pollution is concerning on that planet
- thehappypm 5y agoI understand this sentiment, but preventing cancer and pain is a pretty good reason to generate some trash, in my experience. there's a lot of truly wasteful plastic use out there, but I would not say this is one of them.
- yummypaint 5y agoTried it and it says i have 12 hours to sunbathe before burning... I thought the site must be broken, then looked outside and remember it's the middle of the night. Touche
- paco3346 5y agoMine said 60 hours. It's unclear to me if this takes the current time into account or if it's just looking at a normal, sunny day based on your location and time of day.
- malf 5y agoHaving 0 as an option for SPF annoys me to no end.
- tompagenet2 5y agoI get wildly different results for London (7 hours+) and my postcode in inner London (Wood Green area) (2 hours ish). I also get the 7 hour result if I enter "Wood Green".