How UV Causes Cancer and Aging

[@JarrodsTech]

*sits inside consuming vitamin D tablets*

[@thasonicfan2000]

Jarrod! Thanks for helping me find a laptop 👍

[@MrShubham37]

I don't think you have watched vitamania

[@goharawais5335]

cod liver oil all the way m8

[@erickpeculiar823]

Just eat oranges

[@DarylCarboxylate]

Erick Peculiar orange doesn't have vitamin D

[@kevins8646]

This is why I apply sunscreen on my windows.

[@florisr9]

Lmao

[@rockstar100ify]

You're joking but window tint helps with harmful UV rays. It may not protect you entirely but it still helps! Get your car windows tinted people! If it's legal in your state.

[@kklogins]

@@rockstar100ify makes it really hard to see at night though. Not worth the increased risk of an accident in exchange for a little percent less UV. Just apply the cream mate.

[@40seconds25]

There are types of tint that are less dark than typical tint while being just as effective. Only issue is that it's more expensive. Look up ceramic tint.

[@rockstar100ify]

Danny M. Roque Carbon and Ceramic window film work differently than the cheapest film (dyed film) that obstruct your vision at night, and if you want to be extra cautious you can always get a lighter film (50% light & 35% medium) while still blocking a good amount of VLTR, UV & IR rays. Source: I am a residential and automobile window film installer.

[@karateparkinglot]

Being an introvert has never been safer!

[@AMan-xz7tx]

Awesome! Now i can live longer AND watch copious amounts of anime! Thanks veritasium! (＾U＾)

[@tomasgarcia1576]

Im arming myself with excuses ...

[@Mormodes]

Oh man, if only you knew a year ago how much more true that is now!

[@nnggghhaa3709]

actually it is since you're probably getting no vitamin d

[@beligosk]

"Go outside and talk with the neighbour" "Cant, skin cancer everywhere"

[@thewhitexican7075]

4 years later and your video is the only one that actually explained how radiation does damage. Love your vids

[@BhanuPChauhan]

Video games are more effective than sunscreen to prevent sunburn.

[@rewer]

Bhanu Pratap Chauhan, lol

[@videogyar2]

In an alternate universe: Mom: Son come back inside, the Sun is bad for you. You have to play more video games.

[@skop6321]

Anyone have a portal gun or something ? id love to "visit" this world and "meet" the other me.

[@HuyV]

Seeing the amount of time people spend on mobile games....nope, not true

[@lil_weasel219]

Actually screens produce some small amount of UV light, CFL backlight even causes quite a bit. Also the blue light from screens is bad for the eyes and endocrine system either way

[@PowahSlapEntertainmint]

Ultra violet is too intense, I prefer regular violet.

[@AbhayChandraYouTube]

Medium rare violet.

[@oskarkrogsgard3014]

Wow you have two top comments, well done (pun intended)

[@leonardofls91]

Tessa Violet

[@childfs6865]

It's ultra violent to your DNA!

[@TheFourFats]

that’s the only mode I played Doom on

[@ZEbelgiumfreak]

My butt is hairy and has stretch marks. I don't want my face to look like that, so I am fine without sunscreen, thanks.

[@shanhussain6114]

Lol 😂

[@L.A.97.]

Get zits on the butt too so...

[@No-hf1xq]

You don't have hair on your head?

[@andriyostry]

Gergely Abádi he said face and that’s not the same as head

[@RomanoPRODUCTION]

#SoSexy

[@playc.holder6432]

“Look at butts” -Veritasium 2018

[@nuovoaccount998]

Not valid for girls these days

[@PowahSlapEntertainmint]

It's a good thing I never go outside...

[@cup_check_official]

but you still age... So whose the winner here?

[@rjpena6273]

but vitD

[@2450logan]

Judging from your profile picture, you never went to art classes either.

[@xiaoxiaoxiao686]

Tu Morrow me too

[@danielm.6476]

Rj Pena vitD additives solve that problem

[@NightFlutter]

the irony they are filming outside

[@dhruvthakur1036]

They didn't say outside was harmful dumbhead

[@whatshisnamegain1]

@@dhruvthakur1036 Who said they didn't put sunscreen before filming?

[@herlock2]

So what? Because they are making a video about skin aging they should be in bunkers 5 meters underground in all next videos??

[@MRrealmadridRaul]

Pretty sure that was a joke, you need to calm down.

[@fgnoyola]

I doubt it,,, both are wearing make up.... unlikely...

[@exoplanets]

Each of your videos is a joy !

[@nothingbutfunstuff8506]

Dr.hayley's voice is awesome. *I love voices like that* . . . Btw he was just saying exactly whatever dr.hayley was saying with mild explanations, not fair man

[@omerangi4695]

From now on, whenever someone will ask me what is my favorite color I will give them a wavelength in nanometers.

[@infinitiv525]

Sounds good, doesn't work for black

[@beskamir5977]

Hue isn't the same thing as intensity. Wavelengths can basically only get you hue unless we consider a wavelength of 0nm to be lacking any signal and thus is black. For intensity you'd need to mention the amplitude or frequency (not sure which one? not a physicist) of the light you're referring to.

[@miljantodorovic31]

Color is a lot more complicated than that. Not all light is monochromatic, for instance try to find the wavelength of pink. Beskamir you are talking about amplitude, since wavelength is pretty much determined by frequency.

[@Tom-u8q]

Colour is three-dimensional.

[@gemgal68]

@@beskamir5977 hmmm... since black means non of the wavelenghts in the visble light spectrum gets reflected to our eyes, u can probably define black as "except wavelength of XXX nm (red) to YYY nm (indigo/violet) ...

[@MrWombatty]

Apparently cosmetics that have petroleum oil in them will also age your skin faster as it prevents your natural oils from functioning properly & the hydrocarbons can slowly destroy collagen in the skin (smoking also accelerates this aging process), so choosing a good sunscreen that doesn't damage your skin at the same time is also equally important! While my younger brother covers what's exposed as he runs a landscaping business working outside daily, he also is a redhead & fair-skinned like my sister (who fortunately moved to Estonia as hubby's family originated from there), & my older brother was blonde (now 61 & quite white), I look more like my father's side of the family! Even though I turn 60 in 15mths, I spent 18yrs after leaving high-school working long hours inside with little time off as my health was deteriorating, until eventually unable to work even part-time. Was finally diagnosed with ME/CFS over 20yrs ago with a back-injury & arthritis complicating things in the last 10yrs, but the strange thing is that despite feeling a lot older at times, people often mistakenly think I'm about 40ish as my skin isn't very sun-damaged & my thick hair has only a little grey (Prof. Brian Cox is greyer than me)! Also don't consume caffeine nor much alcohol (due to medications), so not sure whether they're contributing factors along with my genetic make-up! However, quality of life is still far more important than how we think others perceive us by the way we look!

[@thej9589]

This is the best sunscreen commercial I ever seen!

[@mohammadaniyal]

Derick, the physicist whose more interested in biology than physics

[@23Scadu]

All biology is physics. (All physics is maths.)

[@Boog_masskway]

Both chemistry and biology are just applied physics at different levels of abstraction

[@mohammadaniyal]

Just to clarify, I love biology and physics and i like dericks videos i just commented this for nothing particular

[@mohammadaniyal]

@@23Scadu there is fair bit of chemistry involved as well what about that?

[@23Scadu]

@@mohammadaniyal I would refer you to boog_masskwé's comment.

[@canaldoxerxes]

How UV causes cancer: it plays Fortnite into your DNA.

[@florisr9]

Makes sense since Fortine = cancer

[@canaldoxerxes]

Exactly!

[@2Axiom]

lol

[@deathIeaf]

Lol

[@wyattb3138]

I understand now -0-

[@irandom419]

As someone that suffers from a condition exacerbated by UV I'd like to make one point. The windshield is a sandwich with plastic in the middle that better blocks uv than the single plate glass used on all the other windows. I'd always feel better in the car when driving northbound and that tidbit helped me manage my disorder.

[@cbrjune8658]

Little known fact, my butt actually receives the most sunlight of any part of my body.

[@samnub7912]

*pokes butt out of window*

[@yomama3926]

Doing what

[@nuovoaccount998]

Let me guess, you're not a man

[@aeabottss22]

Everytime she talked, I got this feeling that I needed to clear my throat.

[@zvpunry1971]

Many day creams and similar cosmetic products contain UV protection, just like sunscreen, but it isn't mentioned on the label. It would be quite interesting to look at different products with that UV-camera. ;)

[@nickgoldyscreams]

It's very respectful that you present information discovered for this video not SOLELY as YOUR idea.

[@Lugmillord]

Ha! Skin cancer can't reach me! I'm a cave-dwelling nerd.

[@drizzlingrose]

random chance doe :O

[@destroya3303]

You'll just get every other kind of cancer then

[@lil_weasel219]

No, melanoma will reach you harder. Other types of skin cancer however? Extremely easily. Overall you are more likely to get skin cancer in fact.

[@ciencias3344]

I am surprised you only talk about the negative side effects of UV but we need UV. There is so much more about UV and also... sun screens. I love your videos, this is the first one that I see that does not tackle misconceptions in the right light.

[@Imilmano]

4:30 Hey Veritasium, Derek here.

[@abhijithravikumar5300]

Where are your dinosaurs?

[@abhijithravikumar5300]

*Uncomfortable pause ensues*

[@leebee1100]

Abhijith Ravikumar lol omg this thread was so worth my endless scrolling

[@indrashispowali]

It's always FUN watching Veritasium

[@nickipelazza8727]

The best anti-aging cream is called sunscreen!

[@nickipelazza8727]

Sunscreen before going outside (ideally even indoor if you're behind a window) + a retinoid before bed is the best anti-aging combo for your skin. Ask any dermatologist and I don't think they will disagree

[@martinsthalles]

Sunscreen *is* great for anti-aging of your skin, but remember to get your vitamin D or your bones will suffer a bit.

[@whateverppl1229]

nah, the best anti-aging cream is a windowless room that you never leave

[@JaviGis]

@Democracy/anarchy is minority gang/scum rule educate yourself with different sources. And try to spend an hour without sunscream in the Sahara. Let's see if your skin is more or less damaged by the sun than if it would have had sunscream on.

[@JaviGis]

@Democracy/anarchy is minority gang/scum rule literally in just a google search you can find trustworthy information as such: "You may have heard rumors that instead of protecting against melanoma, sunscreen actually causes the disease. However, comprehensive review of all studies from 1966 to 2003 found no evidence that sunscreen increases melanoma risk.5,6" With different and recent studies that back it up. Smh, there's always that someone who's against of anything regardless of the stupidity of their position.

[@Tomas.Malina]

Thymine dimers don't form a hydrogen bond as you suggested in the image at 1:30, the dimers are dangerous because the two aromatic circles of thymines bond stacking on top of each other, it's an addition reaction that forms strong C-C bonds. That is why it's hard to fix for reparation mechanisms (nucleases have to cut out a whole region of tens of bases around the place and resynthethise the whole cut out part of the dna strand, otherwise the strand can't be transcribed - that's the problem with resynthesis errors causing mutations, because not just the thymine region gets repaired), weak H-bonds are not so much of a problem if formed in the wrong place, they don't hold too tight.

[@katieobringer1160]

I work at a nursing home, and I can confirm, old people, do NOT have perfect butts

[@McRocket]

Thanks very much for this. I hope LOTS of people see it and take it seriously.

[@nitarayz]

3:10 that’s Anatoli Bugorski, he was the scientist who accidentally got his head inside a particle accelerator while it was active and survived the incident. The picture was the result of that accident.

[@seededsoul]

NitaRay Yeaaa ironically, the young-looking side is the one that was stuck in the particle accelerator 😂 Shame on you, Veritasium Derek, for not doing your research. There is a picture of an old woman which is what you're looking for.

[@iwillworkhard1]

i couldnt find any reliable source (or any source) that correlates this picture to anatoli bugorski. howver i found multiple sites referring to the pic as a trucker with sun exposure

[@David-ud9ju]

Everybody on the internet says that that is a trucker not a physicist. He even had a case study written about him. Also, Bugorski didn't get wrinkles on the left side of his face; opposite to this guy. www.nejm.org/doi/full/10.1056/NEJMicm1104059

[@nuovoaccount998]

he doesn't even have russian somatic features stop bs

[@alkal1339]

Windshield is triplex, which contains polymer layer inside, so it does absorb UV light including UVA. Side glass doesn’t absorb UVA thus you are susceptible to UV light and your left arm aging with greater rate.

[@pjaa2008]

I love this! It'll be great for introducing what sun does on a cellular to my daughter, who has XP, to people who can't quite wrap their head around it.

[@feykroTV]

This video is a great warning against both skin and throat cancer, yay !

[@waynecanning7471]

You didn't mention anything about the benefits of sunlight. Surely there must be some?

[@loluser124]

Vitamin D synthesis.

[@blue_rapier]

also they are psychological benefits, getting outside and moving around makes you feel better and can help to deal with depression among other things

[@jamesmnguyen]

Also there's a correlation (not causation) that sunlight reduces the chance of needing glasses.

[@dennisvanruijven4489]

Lowers blood pressure actually by generating nitric oxide. Makes you feel good by generating POMC.

[@t-.-t.]

As someone who was severely vit D deficient. My readings was 5 ( < 20 is severe deficency) The benifits of sunlight is a miracle! I had depression, severe memory loss, i couldnt even stand straight because of my stabbing backpain, muscle pain. I was put on very high dosage of vitD. In a month I felt alive and i feel a 100 times better than before.

[@TommoCarroll]

I always make sure I put sunscreen on bananas, wouldn't want them to peel 🍌

[@cavemann_]

You made me spit my water!

[@ricklaxative1688]

don't rub on them too much they might become harder 💀

[@TommoCarroll]

CircleNoob, I wake up every day with the aim of making some one spit their water. I'm happy you got to be that person! :)

[@annatsukiya]

Aspect Science Goal achieved. LOL

[@Marci124]

I haven't been this satisfied with a Veritasium video for a long time. Lately I felt some parts are overexplained, other areas I'm interested in unexplored. This one had good pacing and was not too obvious.

[@veroxid]

As someone that spent most of his childhood inside with his primary exposure to the sun being when in a car traveling across country, I eventually learned that you can, in fact, get a sunburn and tan in a car; though obviously nowhere near the level from direct exposure.

[@quahntasy]

Its a good thing i never go outside. I will now sit inside and eat up vitamin D tablets.

[@MrBlitzpunk]

Friends: why did you never go outside? Me: im on cancer prevention mode

[@blackparadoxx9656]

3:50 Eating too much Fibroblast will give you the greatest explosive diarrhea known to man.

[@nuovoaccount998]

video or it never happened

[@kashu7691]

Should have posted this at the start of summer!

[@VorpalGun]

What about vitamin D tough? Since I live in northern Scandinavia I have always heard we need to make use of what little sun we get to get enough vitamin D.

[@linkinl1]

Supplements, super cheap

[@maciejp7829]

15 minutes of sun while walking to work is enough

[@YszapHun]

Maciej P but what if you don't get sunlight for literally 5 months?

[@linkinl1]

+YszapHun suppppleeements

[@maciejp7829]

YszapHun even if you have the sun just above the horizon line, that's enough, maybe then some more time than 15 minutes of that sun

[@PhotoVRF]

An increased focus on protecting the skin from sun damage and a change from an outdoor lifestyle to an indoor lifestyle in recent generations has led to a serious problem with vitamin D deficiency in many developed parts of the world. Too little vitamin D means the bones will not be able to grow strong, leading to problems like rickets for children or osteoporosis for adults. Due to the weakening of bones, individuals with low vitamin D levels are more prone to falling. Low vitamin D levels can also cause a poorly functioning immune system, cardiovascular disease, depression, development of diabetes, and multiple sclerosis. It has also been linked to certain types of cancer.

[@ClassicJukeboxBand]

You are correct. The only thing stupider than the advice on this video are the half witted commenters who are too stupid to understand that nature is not bad for us...I'm quite surprised we can even have a functioning society with the low IQ's of these brain dead commenters...

[@lil_weasel219]

Avoiding sunlight completely however causes depression, sleep disturbances and causes certain types of skin cancer (lack of UVB exposure coupled with certain mutagenic chemicals in sunscreens). So avoiding the sun is also bad, find the golden middle expose moderately, not go out for 5 hours and cake yourself in sunscreen.

[@Goatly1]

Balance is everything 🔑

[@alexandrathearmy8464]

Caking yourself in sunscreen does you a favor,because vitamin d gets broken down by UVA exposure.

[@juli3836]

Avoid sunlight completely, use sunscreen and take vitamin d supplements.

[@nuovoaccount998]

I think you missed the point, avoiding uv doesn't

[@merionis]

I was about to the picture at 3:08 but did some digging (which everyone should do before writing) and found out I was wrong, I was about to tell you that the picture was not an illustration of sun aging, but of Anatoli Bugorski. I couldn't find evidences that the picture is related to Bugorski, but now I just think an episode on Anatoli Bugorski would be cool.

[@mykevelli]

One of the things I've always wondered is if the same rays that cause skin damage are the ones that tan our skin. Is it possible to separate the two and come up with some form of safe tanning or are they literally two effects of the same thing?

[@lunkel8108]

They are kinda the same thing. Both are caused by exposure to UV radiation, however the damage is a direct result of it and tanning is a defense mechanism of your body against UV. That's why people with dark skin sometimes have to take vitamin D supplements when they live further away from the equator, their skin blocks out too much UV.

[@wana2dmaxmax233]

You could always use a tanning lotion

[@nuovoaccount998]

no they're the same, melanin is a defense from happening dna damage

[@rayawira]

She would be a really great teacher.

[@jacobeamor2052]

Solution: Entire world changes their sleep schedule around 12 hours. Everyone works at night and sleeps in the day :P

[@leebee1100]

Jacob Eamor already there. If the rest of the world would join me that’d be great

[@dumbledoor9293]

Or even better, let's sleep day'n'night

[@jacobeamor2052]

OR.... We could euthanize everyone on the entire planet. Can't get cancer if we're already dead 😂

[@David-ud9ju]

Sleeping during the day and being up in the night really fucks with you though. It leads to all kinds of problems and eventually premature death.

[@brandonford1125]

Like vampires

[@physikascience6078]

Hi Derek! Just wanted to tell you that you inspire me sooo much. Ps. I love your telescope

[@hornetluca]

0:42 everybody is now looking at its own butt

[@zvpunry1971]

No, nobody does that. We are all too lazy to stand up, instead we keep sitting on it while watching youtube. ;)

[@hornetluca]

Come on, you did it. There's nothing to be ashamed of

[@zvpunry1971]

Why should I? I know my butt very well and I'm sure that it is still there because I'm sitting on it. ;)

[@hornetluca]

@@zvpunry1971 😅

[@krazedgunner]

I will quote, You butt looks like Freddy Kreuger face-fucked a topographical map of Utah

[@bennguyen1313]

There was a great HumanOS podcast episode (#66), that talks about the complexities of UVA/B, and could explain why Vit-D supplementation trials have not been very promising, as it may be due to UV , Ntric Oxide , Interleukin-33, cytokine, etc. For example, UVB and UVA tends to activate regulatory B cells that *dampen the adaptive* anti-tumor/immune system.. which could be the reason why autoimmune diseases tend to increase as you go further from the equator. However, this immune system suppression may also lead to more cancers. Interestingly, UV tends to *increase the innate* immune system, useful for bacterial infections. And while long term UVA exposure is associated with Accelerated Aging/skin cancer, even low doses of UV are associated with keratinocyte/non-melanoma skin cancers. But on the flip side, UVA appears to lower blood pressure and reduce the risk of CVD. Most surprisingly, however, is that while short high exposure of UVB can lead to menaloma skin cancers, it may help with weight loss.. DESPITE the fact that UVB prevents the HFHSD-induced Uncoupling-Protein-1 in Brown-Adipose-Tissue from activating.. so the weight loss must be due to something else (UV-induced cytokines like IL-33, NitricOxide, Hydrocarbon signaling in the Liver, etc). BTW, Chris Masterjohn mentions how ultraviolet destroys riboflavin (as does losing weight/exercise)! See 23127244 for how microbes can also lead to autoimmune diseases.

[@sadabahargeet6405]

Dark and brown people( No need of Suncream) Biological Advantage

[@candigirl8180]

Myth XD

[@nuovoaccount998]

yeah but you also have genetic higher risk for melanoma which is ironic, and anemia

[@kylehughes7826]

If a glass window is tinted, does that help restrict the amount of UVA rays that pass through?

[@reactive7748]

I'm black so my higher pigmentation protects me plus I can't wear sunscreen or at least most types since I'm allergic

[@maracachucho8701]

But you're black...

[@josephine190]

@@maracachucho8701 yes the sun doesn't hate him

[@josephine190]

@@maracachucho8701 also doesn't age in dog yeats

[@reactive7748]

@@maracachucho8701 what is that supposed to mean?

[@kimberlythomas2296]

If your black please don't put those chemical on your skin, you don't need them!

[@rickvian]

ah, doing interview about UV under sunlight is a great idea I like it

[@feynstein1004]

3:18 "Longer wavelength penetrates deeper." Um what?

[@tommyjohn3525]

Not that kind of penetration.

[@laurgao]

haha lol

[@feynstein1004]

+Tommy John Lol I know, man. I meant that it's shorter wavelengths that are supposed to penetrate deeper iirc.

[@xyanide1986]

No for any wave be it sound or photons the shorter ones penetrate less. That's why you can hear bass through a wall and not the highs, they bounce off.

[@WaveOfDestiny]

A long enough wavelenght can easily pass trough objects that are smaller or the same lenght, like radio waves or wifi trough walls. A short enough wavelenght can pass trough the space between your molecules or even atoms, for example gamma rays.

[@Lambda_Ovine]

Imagine that. All my summer jobs this past 5 years have been nothing but intense sun exposure (construction and sidewalk survey) with little to non protection but a baseball cap and sunglasses.

[@ninjamaster3453]

Does testosterone in high natural levels or exogeously added beyond therapeutic levels, age the body faster. People who use this as a drug for sports seem to look older than their true age. I'm curious to the science behind it.

[@feynstein1004]

Even then, those people inject way too much T into their systems. You'd never reach those levels naturally. So I don't think it's possible for testosterone to age you.

[@nibblrrr7124]

There might be confounders in your observation: high T can cause male pattern baldness (which looks older but isn't necessarily a sign of bad health), and at least in bodybuilding there's this weird "super tanned, super dehydrated skin" ideal for competitions (which will cause skin aging unrelated to T)? Idk... I think I remember studies correlating (!) higher T with slightly longer age in men. But from what I've heard, the medical consensus (not to be confused with the T supplement industry...) seems to be "don't mess with your hormones unless they cause you severe issues".

[@Softnsweetbb]

I don’t know if it actually ages you , I think testosterone has certain properties that can give that effect though. For example, fat deposits on the face are associated with two things, youth and femininity. High levels of testosterone, eliminate fat in the face (unless you’re a bigger guy, or due to genetics). On high levels of t, fat in the body melts much easier , and hardly distributes to the face. This can make your skin paper thin, and your face gaunt. Thin skin is also prone to wrinkles. High levels of testosterone causes hair to thin, receding hairline and balding. And lastly, facial bone structure is altered, with high levels of testosterone. Bigger chins, bigger brow bones, bigger jaws, all these things combined will make guys (and even some female body builders) look much more masculine, but also much more older than they normally would be.

[@nuovoaccount998]

Biochemical individuality is king in aging

[@CrucialMuzic]

Very well explained as usual. Love your videos :)

[@steveoh9025]

@ Veritasium This video has me wishing for more detailed investigation into other forms of non-ionizing radiation e.g. WiFi and 4G or 5G.. some researchers say it isn't as safe as the consensus has been presuming. Any chance for a vid on that?

[@jaxleigh7335]

Steve Oh That’s more likely causing all cancer not the sun. Great message bro 👍

[@steveoh9025]

@aud_io worried? no. curious about where the frequency range for health impacts from non- ionizing radiation begins? yes. As far as I can tell, no once has approached a determination specifically.

[@steveoh9025]

@aud_io yeah, that's anecdotal. I'm seeking scientific rigor. Thanks anyway

[@David-ud9ju]

​@@steveoh9025 If wifi, 3g, 4g, etc. are damaging then visible light is far more damaging just as UV is far more damaging than visible and x-rays are far more damaging than UV and gamma rays are far more damaging than x-rays, but thankfully the atmosphere blocks UVC rays, x-rays and gamma rays from the sun, which is why we only worry about UVB and UVA. There is some evidence to suggest that blue visible light can cause photoaging the way UVA can, which is what you would expect since it's a spectrum; the cut off between UVA and visible blue is an arbitrarily defined number, so low UVA and high visible blue are essentially the same. However, the radio waves that are used for wifi and 4g and nowhere near powerful enough to harm us.

[@AnkitKumar-dl7mo]

This prooves that everything have a good and a bad side

[@joubess]

You didn't mention the one good thing you get from sun exposure to your skin that is vital to your health: vitamin D! The most bio-available form is from what is produced in your skin. You must get at least 10-30 minutes of unprotected sun exposure at least 3 times a week to make sufficient vitamin D in your skin to properly absorb calcium and phosphorus and make denser bones. I'd rather risk a few skin lesions from some unprotected sun exposure than a broken hip from severe bone loss. Since the sunscreen craze many more people have depleted their blood levels of vitamin D and are showing osteopenia and osteoporosis in hips, pelvises, femurs, and spines around age 55 on bone density scans. Get a little unprotected sun! It's good for your bones!

[@iceapitsada1137]

this deserves much more attention. thank u!!

[@vichgold384]

Love it, thanks!!!

[@ImRezaF]

You can get vitamin D from other sources

[@gareonv1652]

Talks about aging and skin cancer caused by UV, talks outside when the sun is out*

[@sebastianelytron8450]

I was born a sun worshipper. I will live as one, and will die as one.

[@bytefu]

I was born a neutron. I wouldn't probably die as one though.

[@theapocilip]

George Carlin got me into sun worship

[@ilscutta]

At 3:22 she says that UV a have a longer wave lenght so they can penetrate deeper but shouldn't it be the other way around: longer wave lenght --> higher frequency --> more energy --> more penetration right?

[@bibeksunar5120]

Difference between a plant sourced vitamins vs synthetically made vitamins ????

[@stardustpan]

+ skin-made vitamin D

[@Basement-Science]

the vitamin is the same, but I believe plants contain additional other compounds which are needed to make use of some of the vitamins effectively.

[@wantedpwner]

Vitamins are vitamins.. molecules are the same, but I suppose synthetically made vitamins could have molecular 'mistakes', which could be bad. Either way, too many vitamines is bad too, he has a video on that.

[@zied5663]

I think that your channel is more seen then NG. The way you set out things is very simple and nice. You make them look so easy to understand. Thank you

[@the_nerd_99]

what's ng?

[@zied5663]

@@the_nerd_99 national geographic

[@schaflp6867]

So it's actually healthy to stay inside 24/7

[@oh-totoro]

Only if you're in a dark room.

[@skop6321]

well maybe not all day, get sun for like 15- 20 mins for Vitamin D production although i dont do that, probably should.

[@chadd990]

I'm assuiming you ask this question because you're either planning to or do have a dungeon in your basement. Trust me, I know from experience, add some dragons to it, it helps with the atmosphere.

[@nuovoaccount998]

@@chadd990 and candles, electric ones

[@maxischmidt1299]

I want to thank you for your work and for sharing your knowledge, Derek. It is a pleasure

[@Kithanalane]

This is an interesting video. I would also like to a video about the benefits of sunlight. unfiltered sunlight is the best and only source of vitamin D production for our bodies. Doctors have suggested that we do need to be exposed to a range of unfiltered sunlight to promote vitamin D production depending on a persons geographic location.

[@iceman1731]

Sitting outside on a sunny day talking about the dangers of UV light.

[@Abhi-cb7eh]

You just flipped your old thumbnail photo.

[@xCarlos1991x]

Is called Thymine dimers, and is the way we repair that damage which makes it more prone to mistakes

[@lierdakil]

While it's widely known that UV can cause skin and DNA damage, the veracity of the way you spin this is at best questionable. For one, you do need *some* exposure to UVB to produce vitamin D₃, deficiency of which is linked to various chronic illnesses (PMID: 29124697, PMID: 16005208). For two, overreliance on sunscreen can cause more damage than lack of sunscreen. Studies show most people don't understand sunscreen labels, don't apply it correctly (recommended amount according to some sources is 2mg/cm², while most people use at best half as much), and increase their sunlight exposure assuming that they have nothing to worry about since they use sunscreen (which is obviously not true if you think about it for a second).

[@versacemoonbeam]

With the "bottom line" most in mind in the formulation of the "average" (topical) sunscreen that includes "inactive" ingredients that are of detriment to the "application site" and which "consumers" operate on the assumption that the uni-dimensional marketed "purpose" of the product would be inclusive of a much grander negative benefit encompassing general skin (and body) health than the rather reductionistic designated/labeled "purpose" ("To prevent sunburn"). The non-macronutrient (to which they're assumed to be "irrelevant" to ""normal", i.e. baseline mediocrity, or "proper" functionality of the human body from the nutritional facet of health) phytonutrients, carotenoids, provide innumerable "benefits" (with the supplementary, or the generic non-essential, connotation of that term exuding from it) as photoprotective properties (from light absorption) conjunctive with their antioxidant qualities that supply whole-body coverage from the inside (since of course, "Beauty is on the inside" while the interplaying ouside is "on" that inside), with even lowly processed tomato paste demonstrating such. Manifold, holistic solutions sour convenient Mammon-seeking models, their extensions, and instilled consumer "lifestyles". www.ncbi.nlm.nih.gov/pubmed/23053552 academic.oup.com/jn/article/132/3/399/4687282 academic.oup.com/jn/article/131/5/1449/4686953

[@rohanmisra7346]

True, but most people need very little sun exposure for the vitamin. If you're fair skinned, a few minutes in the sun is more than enough. It's hard to avoid at least a few minutes of sun exposure daily. Plus vitamin D is stores in the body, so on days when you have less sun exposure, you still have your reserves. In the winter, it's virtually impossible to produce vitamin D from the sun if you live 37 degrees above the equator (or north of Atlanta), because the sun never gets high enough in the sky for its ultraviolet B rays to penetrate the atmosphere. Exposure to sunlight for the vitamin D is a pointless exercise in winter, and you're just opening yourself up to further damage without any of the benefits. There's also the issue that "healthy" levels of vitamin D are not clearly understood. By the current metric for vitamin D in blood, much of the world's healthy population is deficient, even in tropical countries. It's perhaps more likely that the initial levels for vitamin D were poorly understood, established from blood samples of young white surfers, who would have unreasonably high levels of vitamin D from sun exposure.

[@lierdakil]

@Rohan Misra, I'm not entirely sure why you argue this point? I mean, great addition, sure. I'm not entirely sure about "a few minutes" being enough, but seeing as I'm not an expert on the subject, I can't really argue otherwise. But the way you structured it grammatically indicates you're disagreeing with something I said? I did *not* argue people need to ditch sunscreen and all go sunbathe for hours daily, did I? My point was (and is): the way the narrative in the video is structured ("spun"), it would seem that UVB (and UV in general) is "the silent enemy that will kill you with cancer" and that sunscreen is great and will save you from the Sun's "UV deathrays" -- both of these inferred statements can be considered true only if you squint *really* hard, from where I'm standing, and so I challenged those. First, reminding that humans (and most mammals actually) need some UV exposure to produce an essential vitamin, and total lack of sunlight exposure won't make anyone particularly healthy, long-lived or cancer-free (as some comments here seem to suggest jokingly). And second, asserting that sunscreen isn't the silver bullet, as the video seems to present it, and that believing it to be can and likely will cause harm.

[@rohanmisra7346]

@@lierdakil you're arguing from points of extreme here. From the numbers, deliberately seeking out sun exposure simply for vitamin D isn't advisable for most people. I didn't suggest that your point is to ditch sunscreen altogether and sunbathe, and I don't see how you get that from my comment. I appreciate your point that some sun is beneficial, and perhaps Derek should have mentioned it in his video. The fact that people might overestimate the safety of their sunscreen is something I think he covered in his previous video. As to the point that some sunlight is beneficial for health, sure, but it's also a lot less than most people end up getting, even accidentally. For most people, beyond a few minutes, the damage from sun exposure quickly outweighs the health benefits. In winter, no amount of sun exposure is going to give them the required amount of vitamin D anyway, so they have to get it from dietary sources. Even with sunscreen, the protection isn't perfect, and nobody is going to develop a vitamin D deficiency from too much sunscreen.

[@lierdakil]

@Rohan Misra, I deliberated answering you point-by-point but will resist doing so for the sake of brevity. I can agree with most of what you say here. I do indeed tend to exaggerate a bit in these Internet discussions, at times employing hyperbole even, for the sake of making a point more clearly, especially when arguing counterpoints. Sorry if it's a bit misleading. Never argued for deliberately seeking out sun exposure, sorry if it seemed that way. Still a bit doubtful about the "few minutes" thing -- a few minutes feels like an absurdly small amount of time. "A few dozen minutes" I could probably accept. Could you perhaps point me to some studies (articles) discussing the subject? To clarify further, my problem with this video is it's a bit too one-sided, which can and will beget misconceptions, as evidenced by the comment section (although hard to judge conclusively with all the postmodern irony present) This seems kinda counter-productive, so I felt compelled to provide some counterpoints. Counterpoints that I might have overstated in my quest for simultaneous brevity and clarity.

[@kylehaley5433]

I just got a massive dose of uv this last week when I forgot to button the top collar on my welding jacket. I received an intense sun burn followed by some major chest and sinus congestion. While anecdotal, I think it supports the claim of uv lowering your immune system.

[@civilbeings]

Awesome analysis man! Great fan...will really would like to collaborate with you... kindly give you email address.. thank you!

[@sonicrising6614]

Oh great, now we're gonna have a bunch of people that believe we were meant to live underground.

[@amanmehta2162]

What's a sunscreen and what is sun? 🤔

[@milkywegian]

Aman Mehta keep trying hard to be funny.

[@Louie.Oxford]

What about the downside of regularly using sunscreen?

[@canihave2bucks]

Good lord is that women's throat okay?

[@therambler3713]

probably cigarettes

[@L.A.97.]

Maybe she's given a lot of head recently?

[@ZweiZombies]

Maybe it's just her voice :P

[@martinsthalles]

Her voice isn't even that bad, have you ever talked to people?

[@georganatoly6646]

Pretty sure listening to people gives you ear cancer and the best way to prevent ear cancer is to wear ear plugs when someone is trying to talk to you.

[@jackmcwey3809]

This guy brings so much joys to life.

[@borissman]

i never get disappointing in you, Veritasium

[@TWIGROCKSTAR]

i like how there both outside in uv radation while talking about this

[@vdiitd]

Thanks for another great and informative video. Can you please also tell how do we get the Vitamin D then? Because what we generally hear is that sun is the best source of Vitamin D.

[@Derhemion]

UV light causes the body to produce vitamin D (specifically, UVB), which is essential for life. The human body needs some UV radiation in order for one to maintain adequate vitamin D levels; however, excess exposure produces harmful effects that typically outweigh the benefits. Source: en.wikipedia.org/wiki/Ultraviolet

[@brawnstein]

An upload right after I finished Vitamania . (sweet)

[@TheEedis]

You really tell that she knows A LOT about what she's talking about.

[@Andy__A]

At 3:20: "... a longer wave penetrates deeper". Should it in fact be opposite because a longer wave has less frequency and energy? Or if it relates just to the wavelength, does it still have enough energy? Because otherwise it should have been blocked or unable to penetrate.

[@Octamed]

All those hours on my computer when I was a kid, being told to go outside. Now I'd be praised for my sun smart attitudes.

[@TheCBC1984]

another thing to note is that when one strand is broken it can lead to a double break.

[@ricardo.mazeto]

4:12, dumb question, but was that really sunscreen? Because it looks pretty dark under the UV camera.

[@hebrewisraelitescharleston843]

I'm glad I'm black in times like these😊😊

[@samthixos1746]

My mom has just recently started getting a couple wrinkles, she turned 71 last December. She puts on sunscreen basically every day. Has been for most of her life.

[@joubess]

Has she had a bone density scan?

[@rafiashraf2769]

Genuinely thought I was watching an ad at the start. No joke.

[@BadHabitMarco]

I think Dr. Hayley has a very beautiful voice!

[@jamenneel342]

I like the physics-type videos better than the health-type videos.

[@fynn.dresler]

Did anybody else realize the kid falling about the rope in the background? It totally took away my attention but was very funny :D for everybody wondering it is at 3:16

[@blakhhh]

At 3:15, isn't that Anatoli Bugorski, the guy who put his head in an active particle accelerator? Seems like a mistake of his image if it is.

[@nuovoaccount998]

no it's a guy with unilateral dermatoheliosis

[@BioniclesaurKing4t2]

Sunlight causes you to age faster? I guess I'll look like a teenager for life.

[@ricklaxative1688]

That's why in every summer in which I get baked by the sun I also seem to get a slight cold for a few days. Intresting stuff