Skin cancer and sunscreen myth.

[Trekker4747]

Does sunscreen prevent skin-cancer from exposure to the sun? Maybe, maybe not.

Does sunscreen prevent a painful burn on me that causes my skin to peel off like I'm a molting lizard? Yes.

I think I'll continue to use sunscreen.

 

[thestrangequark]

How the heck are you supposed to spend all day in the sun if you burn without it?

Maybe we need to go back to parasols.. nah.

I was actually considering a parasol today. I could totally pull that look off.

I'd still wear sunblock, though.

 

[Marc]

The long and short of it is that science isn't sure whether sunscreen use prevents skin cancer in the long-term, though most sunscreens are unquestionably effective in preventing sunburns.

But does the burning cause any damage that long increases the risk of skin cancer?

If so you could argue that by preventing damage to the skin that can lead to skin cancer, sunscreen does help in prevention.

 

[HIjol]

From growing up in Chicago and now in the Middle East:

No Sunscreen = Lobster Red Skin, Blisters, Fever, and then Skin Peel City!

Sunscreen = Phosphorescent, Glowing at the Beach Skin (as usual), no
Blisters, no Fever, no Peeling...

@Robert^ ...yeah...funny, a little girl with a dog rang my bell the other day...something about "...tan, don't burn..." and the dog was pulling at her drawers...figured I had better close the door...

 

[MacLeod]

Of course there are also things to consider such as

Brand some brands might be more efficent than others
SPF
How it's applied to the skin i.e was it applied correctly

Lots of things can affect an outcome.

 

[Amaris]

 

[auntiehill]

^ I need that, along with a label that reads "Do not place in direct sunlight."

 

[Amaris]

^ I need that, along with a label that reads "Do not place in direct sunlight."

We also offer complimentary lead shielding.

 

[scotpens]

How the heck are you supposed to spend all day in the sun if you burn without it?

Maybe we need to go back to parasols.. nah.

Or beachwear that looks like this.

 

[SPCTRE]

^ Gasp! Exposed knees!

 

[Robert Maxwell]

The long and short of it is that science isn't sure whether sunscreen use prevents skin cancer in the long-term, though most sunscreens are unquestionably effective in preventing sunburns.

But does the burning cause any damage that long increases the risk of skin cancer?

If so you could argue that by preventing damage to the skin that can lead to skin cancer, sunscreen does help in prevention.

It's not a question of arguing it, it's a question of whether it's true. Right now, science isn't sure. The issue is that one may have any number of sunburns over a lifetime, and should skin cancer occur in that person at some point, what is the likelihood you can attribute it to excessive sun exposure?

Supposing we know that much, how do we determine the long-term efficacy of sunscreen in preventing or reducing cancer-causing sun exposure? Only recently have sunscreens that block UVA become commonly available, and while UVA doesn't cause sunburns it can cause cancer (by damaging your cells' DNA.) So the thing is, it's entirely possible that people have been using UVB-blocking sunscreen all these years, thinking it's kept them safe, while UVA is slowly causing invisible skin damage that leads to cancer. In that case, the sunscreen didn't really help, or at least not enough to matter.

Of course, there is nothing to substantiate the crackpottery in RAMA's OP.

 

[Jedi_Master]

Has any of these geniuses (the sunblock causes cancer conspiracy nuts) ever thought to check what the average annual amount of sunlight that the group who "regularly" uses sunblock is exposed to, and then compare that to the average annual amount of sunlight that the group who does not use sunblock is exposed to rather than use just one study or one set of data and base an entire theory on that study or data?

Unless you are amazing at applying sunblock, you will have some areas of exposed skin, and the application of sunblock may allow you to feel more comfortable staying in the sun longer than is safe (particularly in the 10am-2pm timeframe). So the group who regularly uses sunblock might have a higher occurrence of melanoma simply because they are exposed more often and for a longer duration to sunlight than a person who doesn't use it and instead listens to his or her bodily cues to get out of the sun.
Living in a subtropical area with regular sunshine has helped me appreciate that no matter how "good" the sunblock is, respect that yellow ball in the sky and you will save your skin.

 

[TEACAKE'S PLEATHER DOME]

^People who burn regularly don't get comfortable with it because they have sunblock on.

 

[thestrangequark]

Has any of these geniuses ever thought to check what the average annual amount of sunlight that the group who "regularly" uses sunblock is exposed to, and then compare that to the average annual amount of sunlight that the group who does not use sunblock is exposed to?

Harshing on the scientists much?

So, how would you go about doing this? You can't ethically do a prospective study -- because, you know, the whole knowingly exposing people to carcinogens thing is a no-no -- so the best kind of research is out. You're stuck with retroactive, and what's worse, retroactive self-reporting. Let's venture as to how accurate the average research subject would be at retroactively self-reporting the "annual amount of sunlight they get." Even if you were such a creature of habit that you took the exact same walk at the exact same time every day, unless you lived on the equator the actual amount of sunlight you were exposed to would vary greatly over the course of a year. You'd also have to take into account the clothes you're wearing and how much skin they cover. Then you have to be sure that the sunblock is actually applied in the same amount over the same area of skin every time, and you have to make sure that the control group never, ever uses it...all, again, while doing a retroactive study...which is kinda impossible. Doesn't mean organizing a study like this won't give you any data, but it's not going to be the best data, it'll be the kind of data that yields mixed results, which, as was pointed out, is where science is right now in answering the question.

The question isn't unanswered because the "geniuses" aren't doing the obvious things, it's because the "obvious" things might not be as "genius" as you think they are.

Unless you are amazing at applying sunblock, you will have some areas of exposed skin, and the application of sunblock may allow you to feel more comfortable staying in the sun longer than is safe (particularly in the 10am-2pm timeframe). So the group who regularly uses sunblock might have a higher occurrence of melanoma simply because they are exposed more often and for a longer duration to sunlight than a person who doesn't use it and instead listens to his or her bodily cues to get out of the sun.

In the article I linked earlier they specifically discuss this potential false sense of security," but still conclude that sunscreen wins in a risk/benefit analysis. If you're interested in the types of studies being done on the subject, I'd recommend reading that article.

 

[Mr Awe]

Wow, what a quack. The effect of radiation on living tissue is well documented. There is no controversy.

It seems like for every issue that has an obvious answer, there's a loon who can't see the obvious. My only question is about whether he was just dim witted, or was trying to get attention?

There is an issue with sun block but not as he presents it. Those who spend more time outside in the sun will tend to use more sunblock--a positive correlation. According to other studies, those who use sunblock tend to not use enough and/or not reapply it frequently enough so they have more UV exposure, and, therefore, skin cancer--a positive correlation.

Therefore, there is an apparent positive correlation between using sunblock and skin cancer, but you have to understand the full chain of events:
Sun exposure > Using sunblock (incorrectly) > greater UV exposure > skin cancer

Mr Awe

 

[Mudd]

Tanning is an essential part of the cult of bodybuilding; this is not news.

 

[Tora Ziyal]

"women who avoid sunbathing during the summer are twice as likely to die as those who sunbathe every day."

Well, since everyone's chance of dying is 100%, I can't say I find that entirely compelling.

Nope, not compelling at all.

I was actually considering a parasol today. I could totally pull that look off.

Yes, you could. And I want to see pictures!

I have two things to balance -- a history of Vitamin D deficiency and a family history of melanoma. So... I don't use sunscreen regularly, but I do when I expect to be in the sun for a few hours. Luckily I don't burn or even tan quickly.

 

[sojourner]

As a teenager I used to surf for hours on end and would end up with sunburns so bad I would get blisters. Brutally painful to heal through. And that was back when I had a decent based tan. I'm afraid if I tried to get out in the sun these days I'd just burst into flame.

Whether or not tanning causes skin cancer, there's no denying that it ages the skin. Just look at the leathered skin of people that work in the sun all they're live. Anecdotal? yes. but good enough for me on that count.

 

[Jedi_Master]

Wasn't harshing on scientists.... actually was harshing on people who take a single study and extrapolate that an entire industry is out to lie, deceive, and cause cancer.

There are a lot of "writers" out there who use a single set of data to prove that their conspiracy theory is correct, and rarely, if ever take into account facts that don't fit their viewpoint.

That's all. I realize the difficulty of doing various studies, and the difficulty pinpointing the effectiveness of sunblock is a good reason not to dismiss it out of hand or even worse act as if sunblock ITSELF is dangerous.

 

[thestrangequark]

^Well, then. We are in total and utter agreement and I misinterpreted your post before as referring to the fact that science is uncertain on the matter rather than the specific poor science of the OP. Apologies for the misunderstanding, but your post kind of reads that way.