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Why DNA damage from smoking and UV rays cause cancer in some but not others

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Re: Why DNA damage from smoking and UV rays cause cancer in some but not others

#71

Post by dyauspitr »

tartoran wrote: post #46
dyauspitr wrote: post #23

Earlier quoted context omitted.

My mom had 14 siblings and only one of them got breast cancer (she was a nun and never breastfed which drastically increases a woman’s odds of breast cancer). But prior to that, her mother’s family, which was also large never had a case of cancer. My mom’s siblings also had around 30 kids between them some now in their 60s. There hasn’t been a single case of cancer amongst the kids either. So it’s something like 150…

Yes, genetics play a big part but my understanding that cancer is influenced by both genetic and environmental factors. It's possible to have similar habits in the family with respect to sun exposure, alcohol consumtion, diets etc..

Oh definitely, there’s a huge environmental component as well but good genetics really helps.

Re: Why DNA damage from smoking and UV rays cause cancer in some but not others

#72

Post by HedonicEscal8r »

NikolaNovak wrote: post #41
brightball wrote: post #29

Earlier quoted context omitted.

I typically do the same thing. I only wear sunscreen if I am planning on being in direct sun for an extended period of time where I can't easily get back in the shade. The more you're able to build up a base tan the less you need it to avoid a burn at least.

Isn't tanning basically body's reaction to cellular damage? It reduces further damage but that's due to damage done? (It's largely irrelevant to myself, I pretty much burn immediately and don't / can't really tan, but my wife and her family tan well).

Yes, tanning is downstream of the activity of the p53 tumor suppressor protein in response to UVB-induced damage: https://www.lesswrong.com/posts/EFiCGc3YwadZBzvZ3/contra-byr...

Re: Why DNA damage from smoking and UV rays cause cancer in some but not others

#73

Post by gdulli »

dblohm7 wrote: post #70
crims0n wrote: post #47

As a millennial growing up it was beaten into our head that smoking was a death sentence. I recently looked up what the actual cancer rate among smokers was... about 125k people in the US die of lung cancer annual. 25 million people smoke annually. That is a 0.5% chance for occasional smokers. Even if you smoke a pack a day your entire life, the cancer rate is less than 15%. I am in no way saying it is okay to smoke,…

Cancer is not the only complication...

Exactly. Hypertension, emphysema, people who don't smoke not wanting to be anywhere near you,

Re: Why DNA damage from smoking and UV rays cause cancer in some but not others

#74

Post by pixel_popping »

GlickWick wrote: post #69
pixel_popping wrote: post #57

Earlier quoted context omitted.

It's just that getting sun is healthy (in moderation) and our body reward us, we have this new anti-sun obsession which is likely to cause many health (and mental health) issues

I don't think it's that simple, and making it seem that way is counter-productive towards understanding what we should/shouldn't be doing. There's no anti-sun obsession, either. Sunscreen isn't anti-sun, and people are well aware that Vitamin D synthesis is an issue in farther northern/southern latitudes. There's definitely an increased recognition scientifically that excessive sun is extremely bad, though.

I would assume that many are taking Vitamin D, but there is still a major difference, if I spend few days no-lifing and I suddenly go out in the hot sun and comeback home 30min later, I feel much better, something happens internally, could be from the light itself, unsure, but I'd say for example to fight off depression, getting under the sun is quite powerful and will definitely improve your chances of getting out of it.

I let my 2-year old child (she is also taking Vit D - 300iu a day) under the sun in the garden quite a lot on/off (I'd say probably 1h a day in total) and I find that she sleeps much better and is more calm in the evening as well, I can't say the same if we do an outing to the mall, something is clearly different/rewarding.

Re: Why DNA damage from smoking and UV rays cause cancer in some but not others

#75

Post by joe5150 »

tombert wrote: post #37
leawi wrote: post #30

Earlier quoted context omitted.

A bit offtopic, but have you tried different sunscreen types? There are quite a lot of formulations from matte creams to solid sticks. Mentioned because I remember avoiding sunscreens precisely because of that slimy feeling I got from the drugstore ones, that is, until I found an "invisible" one that doesn't feel like anything at all on my skin.

I have not. Do you have any recommendations for specific brands? I'll order a bottle and try it out.

Different person here, but I've been using various Supergoop products for years and think they're all excellent. Their "Unseen Sunscreen" dries completely matte but is kind of pricey per ounce. I mostly use it on my face. "Play" is cheaper (especially if you get the 18oz pump bottle) and still a lot less greasy than most drug store sunscreens. I use it every day.

Re: Why DNA damage from smoking and UV rays cause cancer in some but not others

#76

Post by miladyincontrol »

pazimzadeh wrote: post #66
Rnonymous wrote: post #32

Earlier quoted context omitted.

Care to explain? Isn't UVB more harmful than UVA?

No, UVA is stronger and more harmful. UVA penetrates deeper in the skin, since it's stronger. UVB stimulates Vitamin D production, while UVA doesn't. So almost anything that is "UV-blocking" (sunscreen, UV-treated glass) gets rid of all of the beneficial UVB before UVA starts getting reduced. So you are actually enriching your exposure to the most harmful UV type, and not making Vitamin D. This might explain the para…

Confounding by indication.

People who spend more time outdoors are more likely to try to wear sunscreen, as are people who already got a lot of pre-existing risk to excessive sun exposure.

Key word on try as its greatly assuming there isnt a wide audience who do use sunscreen, then just apply it in poor amount, or never re-apply but enjoy staying out far longer than most do in the sun feeling they're oh so very protected.

Spray sunscreens for example are just about useless, as are those solid stick applicators. They only get a fraction the amount you need for the rated protection. The biggest issue with sunscreen relates to companies selling sub par "convenience" slop, often right beside their other products some of which might actually be half decent.

Re: Why DNA damage from smoking and UV rays cause cancer in some but not others

#77

Post by milesvp »

aantix wrote: post #3

Anecdotally, whenever I go swimming with my kids in the summer, and I don't put sunscreen on right away, but let myself get some intense direct sun, I feel good and sleep really well that night. As long as I don't let myself get in a red, sunburn situation.

Most likely that’s the nitric oxide (not to be confused with nitrous oxide) that is a biproduct of vitamin d synthesis which requires UV light. It is a natural muscle relaxer and is generally considered good for blood pressure and heart health in general.

Re: Why DNA damage from smoking and UV rays cause cancer in some but not others

#78

Post by dsego »

F* cancer. On my mother's side, her mom and sister died of breast cancer, her other sister caught it early, her brother died of cancer (throat or lung, not sure). She removed her breast 20 years ago at almost 50, went through chemo and radiotherapy, she was a survivor, cured. Just a month ago got headaches and turns out new brain tumor. Neurosurgeons removed it, but against all odds nothing to do with the old cancer, not a metastasis, but a new primary wildtype glial grade 4 tumor. It's just not fair.

Re: Why DNA damage from smoking and UV rays cause cancer in some but not others

#79

Post by pazimzadeh »

miladyincontrol wrote: post #76
pazimzadeh wrote: post #66

Earlier quoted context omitted.

No, UVA is stronger and more harmful. UVA penetrates deeper in the skin, since it's stronger. UVB stimulates Vitamin D production, while UVA doesn't. So almost anything that is "UV-blocking" (sunscreen, UV-treated glass) gets rid of all of the beneficial UVB before UVA starts getting reduced. So you are actually enriching your exposure to the most harmful UV type, and not making Vitamin D. This might explain the para…

Confounding by indication. People who spend more time outdoors are more likely to try to wear sunscreen, as are people who already got a lot of pre-existing risk to excessive sun exposure. Key word on try as its greatly assuming there isnt a wide audience who do use sunscreen, then just apply it in poor amount, or never re-apply but enjoy staying out far longer than most do in the sun feeling they're oh so very prote…

Sure that’s a theory, but hasn’t been proven. If I recall, the study showed that heavy sunscreen use amongst sunscreen users was associated with higher cancer rates.

Secondly, if sun exposure is really that bad then how do you explain why most skin cancers are on the trunk and thighs rather than more exposed areas like hands and arms?

The simplest answer is it’s not sun exposure that’s bad but sudden high exposure after non-exposure (repair mechanisms can’t keep up with damage).

Not sure why I’m being downvoted. I guess there’s a lot of sheep among us. If anything I said is incorrect, please show me the evidence.

Re: Why DNA damage from smoking and UV rays cause cancer in some but not others

#80

Post by butvacuum »

Ralfp wrote: post #18
bob1029 wrote: post #13

Earlier quoted context omitted.

I can spend a solid hour in the sun before I start to burn, assuming I have a hat on my head. I've also noticed some correlation between my diet and how fast I burn. Whenever my metabolism is running at/near ketogenesis, it seems like it takes a lot longer for the sun to affect me.

Yes, some stuff make your skin more sensitive to light than others. For example, you should avoid vitamin A creams and some herbs during summer because they increase risk of permanent skin discoloration.

also: citrus- wash your hands after.
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