Time to sunburn • Hacker News Board

Re: Time to sunburn

#71

Post by gojomo » Tue, Jun 15, 2021, 7:15 PM UTC

49531 wrote: post #66

gojomo wrote: post #59

Earlier quoted context omitted.

But, 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 preventin…

> • Known carcinogens commonly used in sunscreens, or present as contaminants, are actually causing increased rates of skin cancer. I am curious to see a citation for this claim. > 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 fou…

Many intentional functional ingredients in sunscreens are known carcinogens and absorbed at levels beyond any safety testing:

https://www.webmd.com/skin-problems-and-treatments/news/2020...

Contamination of sunscreens with common dangerous byproducts of industrial processes like benzene is common:

https://www.washingtonpost.com/lifestyle/wellness/benzene-su...

By comparison, shade contains no carcinogens.

Sun exposure correlated with longer life (even while also being correlated with more cancer deaths!):

https://www.health.harvard.edu/blog/heres-something-unexpect...

An earlier broad survey also finding natural sun exposure decreasing all-cause mortality (but not use of tanning beds, despite similar effects on Vitamin D production, again suggesting D-supplements alone don't replicate the sun):

https://cebp.aacrjournals.org/content/20/4/582

I'd agree, it is hard to disentangle these correlations with things like general levels of outdoor activity and socializing.

But even so: if people who are healthy for other reasons tend to spend more time outside in sun, maybe it'd be a good idea to join them, & perhaps absorb their other habits as well, rather than live in fear of the sun? (Maybe even the sun is damaging on many levels, but the other benefits of activities inherently done more under the sun offset those effects, even if just via mood/optimism?)

I'd say instead that it's an incorrect framework to embrace an illusion of total control "through different lifestyle choices" without tradeoffs. Every activity has a mix of risks and benefits. Certain vigorous activities with a higher risk of accidental death may deliver other fitness and social benefits. If an extra 5 hours of sun every week doubles melanoma death risk, but reduces cardio/cancer death risk just 1%, that sun would still be a net-mortality benefit.

Such tradeoffs are real & everywhere. Trying to engineer both benefits – "can I do everything other healthy people do usually do outdoors indoors? can I find the least-dangerous sunscreen? will vitamin D supplments, perhaps with a bunch of other diet changes, simulate the sun's benefits?" – also includes costs, in research time, psychological focus, neurotic behaviors, etc, for diminishing returns.

Re: Time to sunburn

#72

Post by seattle_spring » Tue, Jun 15, 2021, 7:16 PM UTC

gojomo wrote: post #59

49531 wrote: post #35

Earlier quoted context omitted.

Fortunately 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-preve...

But, 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 preventin…

Can you provide some peer reviewed sources for your claims? Your whole comment reads like that thoroughly debunked "scientists blow the lid off of sunscreen" [1] article that was going around a few years back.

[1] https://millerfamilydermatology.com/sunscreen-myth/

Re: Time to sunburn

#73

Post by psychometry » Tue, Jun 15, 2021, 7:26 PM UTC

gojomo wrote: post #59

49531 wrote: post #35

Earlier quoted context omitted.

Fortunately 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-preve...

But, 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 preventin…

>But the people/populations using more sunscreen are also having more skin cancer

Um, you missed the most obvious explanation (assuming that's even true): People who have an elevated risk of skin cancer (due to geographic location and/or skin type) are likely to use more sunscreen for that very reason, but despite their sunscreen use they're still at an elevated risk of cancer because sunscreen cannot eliminate all risk.

It's really no different than saying that people who are receiving more IV chemotherapy are also dying of cancer more often than people who aren't.

Re: Time to sunburn

#74

Post by wahern » Tue, Jun 15, 2021, 7:28 PM UTC

gojomo wrote: post #59

49531 wrote: post #35

Earlier quoted context omitted.

Fortunately 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-preve...

But, 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 preventin…

> But, after 50+ years of rising sunscreen use, there's essentially no data showing more sunscreen use reduces skin cancer.

50% reduction in melanoma: https://pubmed.ncbi.nlm.nih.gov/21135266/

40% reduction in squamous cell carcinoma: https://pubmed.ncbi.nlm.nih.gov/10475183/

See, generally, https://www.skincancer.org/skin-cancer-information/skin-canc...

Perhaps you were thinking of basal cell carcinoma, the most common type of skin cancer. There does seem to be a lack of experimental evidence wrt BCC: https://www.hindawi.com/journals/jsc/2012/480985/ The skincancer.org FAQ conspicuously skips around that hole.

Re: Time to sunburn

#75

Post by nomel » Tue, Jun 15, 2021, 7:36 PM UTC

psychometry wrote: post #73

gojomo wrote: post #59

Earlier quoted context omitted.

But, 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 preventin…

>But the people/populations using more sunscreen are also having more skin cancer Um, you missed the most obvious explanation (assuming that's even true): People who have an elevated risk of skin cancer (due to geographic location and/or skin type) are likely to use more sunscreen for that very reason, but despite their sunscreen use they're still at an elevated risk of cancer because sunscreen cannot eliminate all r…

The majority of my family has had skin cancer (we don't tan, we burn). It's usually in places you can't put sunscreen, like eyelids, close to the lips, etc.

Re: Time to sunburn

#76

Post by VoiceOfWisdom » Tue, Jun 15, 2021, 7:44 PM UTC

jeremyw wrote: post #21

Consider 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.

My 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.

Re: Time to sunburn

#77

Post by Toine » Tue, Jun 15, 2021, 8:03 PM UTC

loudtieblahblah wrote: post #60

49531 wrote: post #35

Earlier quoted context omitted.

Fortunately 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-preve...

Sunshine is more than just a source of VitD. UVA has also been shown to lower blood pressure. This is probably the result of UVA causing the release of nitric oxide from skin stores, which promotes widening of blood vessels. It also acts as an antioxidant to prevent damage to cells. People who don’t get enough sunlight have altered cellular defense mechanisms that predispose them to excessive inflammation, which can…

That was really enjoyable to read, thanks for sharing.

Re: Time to sunburn

#78

Post by nradov » Tue, Jun 15, 2021, 8:04 PM UTC

49531 wrote: post #35

pmoriarty wrote: post #16

For 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 sunsc…

Fortunately 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-preve...

Your risk analysis is not scientifically valid. There is no reliable evidence that moderate sunlight exposure increases all-cause mortality.

Re: Time to sunburn

#79

Post by mywittyname » Tue, Jun 15, 2021, 8:13 PM UTC

gojomo wrote: post #64

loudtieblahblah wrote: post #60

Earlier quoted context omitted.

Sunshine is more than just a source of VitD. UVA has also been shown to lower blood pressure. This is probably the result of UVA causing the release of nitric oxide from skin stores, which promotes widening of blood vessels. It also acts as an antioxidant to prevent damage to cells. People who don’t get enough sunlight have altered cellular defense mechanisms that predispose them to excessive inflammation, which can…

"I'm betting, not just in this case, but the act of your body making it's own VitaminD creates benefits we are not yet aware - that oral consumption of a pill isn't going to compensate for." We are already aware of a direct benefit: the skin's production of Vitamin D uses up bodily cholesterol. External supplementation doesn't do that. (I agree there are likely others we'll document later.)

Very good information.

Re: Time to sunburn

#80

Post by Spooky23 » Tue, Jun 15, 2021, 8:18 PM UTC

gojomo wrote: post #59

49531 wrote: post #35

Earlier quoted context omitted.

Fortunately 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-preve...

But, 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 preventin…

I don't know why your comment is being voted down, it's a reasonable one, although I disagree with parts of it.

Depending on your skin type, "Get Sun" may not be good advice, especially if you make a mistake. A single significant sunburn in your teens significantly increases your lifetime risk of getting a skin cancer, of which melanoma is just one. My wife developed melanoma and is in remission. She is fair skinned and very sun-cautious -- typically using clothing as a primary barrier with sunscreen. Like anything risk assessment and risk tolerance is key and difficult to assess.

Another factor to consider is that mortality doesn't always tell the story. Some surgical procedures introduce significant scarring. Treatment for a stage-2 melanoma will often include removing lymph nodes, which introduce other complications. Also be careful, as past diagnoses of cancers were not great. That melanoma that moved into an organ may not have been classified correctly in 1960.

Personally, my advice is go outside, dress appropriately and use a mineral-based sunscreen if you're going to be out for more than a half hour or so. Don't go swimming at solar noon. Don't tan. Wear a rash-guard at the beach. Wear a hat at the ballgame.