Transcript for:
Debunking Sunscreen Myths and Facts

hi it's Michelle of Lab Muffin  Beauty Science chemistry PhD   cosmetic chemist big fan of sunscreen  not such a fan of sunscreen myths it's summer for almost everyone but Australians  so everyone is talking about sunscreens I've debunked a lot of myths about sunscreen  before things like sunscreens are toxic you can   make your own sunscreen safely but today I'm going  to be focusing on incorrect advice from trusted   media sources because you would expect them to  be correct and these myths are a bit harder to   spot and they have less obvious but still bad  consequences I'm going to go through a bunch   of sunscreen news articles explain what they  got wrong and what you should be doing instead I don't entirely blame the people  writing these articles because   this is part of a larger problem with  sunscreen misinformation from trusted   sources which we will see hopefully  this will be an interesting excursion like and subscribe for more nerdy beauty content we're going to start with this article  from USA Today called what is mineral   sunscreen and why you may want to  use it instead of chemical sunscreen I'm trying not to have a reaction just to  this headline because a lot of sunscreen   myths end up supporting this idea that mineral  sunscreens are better and safer which is mostly   just confirmation bias for people's gut feelings  that natural things should be safer and better   this isn't true this is just a gut feeling that  we've evolved because back in the day we would   go into the wild and if we saw something  weird it was probably going to be dangerous but these days we have much better ways of working  out which things are dangerous versus safe we   don't have to rely on this gut feeling which  just doesn't really work in our modern world but I guess technically this headline is fair  because mineral sunscreen is a better option   for some people just not as many as the media  and social media tends to make it out to be for most people chemical sunscreens are going  to be a better option and they actually do say   the reasons why so they say there is ease  of application and aesthetic appeal and   these two things are really underrated  mineral sunscreen gives a white cast on   lots of people's skin especially if you are  darker skinned it also tends to feel thicker   and less comfortable so that means a lot  of people don't apply enough or they just   skip applying it all together which is a much  worse situation than using a chemical sunscreen there are currently 14 FDA approved  chemical filters in the US but many   more overseas chemical sunscreens  have very small amounts of systemic   absorption into one's bloodstream so  systemic means it goes into your body   and goes everywhere so it could potentially  affect parts of your body not just your skin this finding has drawn lots of attention however   at this time it is not known that  this trace amount is problematic this is a pretty good summary of those FDA  studies that came out in 2019 and 2020 I   would have preferred if she also mentioned  where the current evidence is pointing so   for example in the EU this absorption  has been known for quite a long time   and so they've always assessed the safety of  sunscreens based on that for like almost 20   years I go into a lot more detail about the  evidence in my US versus EU sunscreens video basically the EU has been re-evaluating  a lot of these older more controversial   chemical sunscreens and there is  still a really large margin of safety she says additionally if one has  really sensitive skin chemical   sunscreens are more likely to cause a  reaction this is true on average for   US sunscreens but on an individual  level this is not necessarily true in Europe for example mineral-only sunscreens  aren't really a thing all their sensitive skin   sunscreens have lots of chemical filters because  they tend to be better at blocking UV they tend   to use the newer chemical filters that don't get  into the skin as easily to cause irritation and   so overall you end up with more protection  against both irritants as well as the sun there's also this issue with SPF boosters which  are these chemical sunscreen like ingredients that   are not strictly regulated as chemical sunscreens  but they have very similar structures and very   similar properties these are listed as inactive  ingredients rather than active ingredients and   so people aren't looking out for them and they  end up reacting and they just don't know why Newsome says mineral sunscreen could  be referred to as physical sunscreen   because it's a physical blocker they're  really really good because they reflect   the UV rather than the chemical  sunscreen that absorbs the UV this is the most common myth in all the  sunscreen articles I've read it is like   the origin of a whole bunch of myths  for why mineral sunscreens are better I made this family tree a while ago  showing how this has birthed so many myths so it's been known for a really long time more  than 50 years that mineral sunscreens also   mostly absorb UV only about five to ten percent is  reflected this is because these mineral sunscreens   have a semiconductor structure I've talked about  it before in my video on how sunscreens work one of the big reasons this myth is still around   is because the American Academy of  Dermatology website still has this there's an article in 2016 that  re-demonstrated that this is   true for sunscreen specifically  but yeah it's just still around this is one of those issues where you  would think you would be able to trust   a source but this is not their specialty  my best advice for working out what is and   isn't true is to look for the consensus of  relevant experts for how sunscreens interact   with UV this is chemistry or physics it  isn't dermatology and so those are the   more relevant experts and the consensus is  overwhelmingly that they work by absorption so there isn't much of a difference they're  not going to be really really good because they   reflect this extra five percent it isn't really  reflected this five to ten percent is actually   scattered and most of that UV gets scattered  towards the skin deeper in to that sunscreen   layer most of the time it'll hit another molecule  and get absorbed which is what we want absorption   is better because it actually takes the UV and  turns it into something else usually mostly   heat the scattering just kind of bounces the UV  somewhere else and lets someone else deal with it Newsom says mineral sunscreen is  a little bit more effective than   chemical sunscreen they have a little  bit broader spectrum of coverage if you look at zinc oxide it does look like  it has a pretty flat spectrum it covers a   lot of wavelengths on its own but if you take  chemical sunscreens and put them together they   cover the same wavelengths and usually they can  get much higher protection so it doesn't really   matter that zinc oxide on its own can cover  everything because when you buy a sunscreen   you're not buying individual chemical filters  this is a problem that is solved by the people   formulating the sunscreen we don't have to  worry about this we just buy the one sunscreen so we're looking for a high SPF rating  and the words broad spectrum or a high   PPD or PA rating that's what these are  there for these directly measure what   sort of protection you're getting from the product the article mentions the issues with  the application and aesthetics people   are less likely to apply the appropriate  amount due to the thicker opaque nature of   these formulations completely  true this is a huge problem however in recent years mineral  sunscreens have come a long way   and there are now numerous products with  a lightweight feel that apply with ease this is true but a lot of the time they are  still relying on those SPF boosters which   are really just chemical sunscreen so really  they are hybrid sunscreens pretending to be   mineral sunscreens which is kind of just false  advertising that I'm not really comfortable with next she mentions that there are tinted mineral  sunscreens which just basically takes the white   cast out of it which isn't entirely true that  white cast is still often there and sometimes   the tint is also not quite the right color  for your face so it's kind of like I guess   two bad things that still  end up making one bad thing but I think looking for a tinted mineral  sunscreen is still pretty good advice this   next bit though chemical sunscreens have also been  implicated in harming marine life in the ocean Newsom says you can avoid this by using mineral  sunscreens as they are very safe there is this   really common myth that chemical sunscreens and  nano mineral sunscreens are bad for marine life   but non-nano mineral sunscreen is completely  safe this is based on this 2016 study by Craig   Downs and co-workers the scientists who did  this study promoted really aggressively in   the media on the day of release which is  pretty unusual I've explained this a bit   more in my video on reef safe sunscreens  as well as in my environmental myths video last year the national academies did a review  of all of the evidence and their conclusion is   mineral and chemical sunscreens overlap in  regard to environmental impact but overall   it doesn't seem like sunscreen has much of  an impact at all because they are massively   diluted the amounts in the ocean are so tiny  and the effect they can have is really really   small compared to things like global warming and  agricultural runoff and land use and overfishing that downs study was a massive outlier there  were lots of issues with how they conducted   their experiments this article links to  an NOAA page called Skin Care chemicals   and coral reefs which is another example  of a source you thought you could trust this page has kind of been haunting me  for a few years because people would   always bring it up in arguments to say the  NOAA obviously knows more about coral than   you do so it's worth mentioning that in the  National academies report which was written   by a lot of coral experts who actually did  the original studies specifically references   this page alongside the ewg and a bunch of other  questionable pages as examples of misinformation the page says NOAA is reviewing the National  Academies study and upon completion of this review   they will update the information presented in this  article as warranted that was done in August 2022   clearly there are still media articles relying  on it so it would be nice if they updated it onto our next article this is from NPR and  it's called picking the right sunscreen isn't   as important as avoiding these six mistakes so I  quite like the overall message of this headline   because there aren't that many differences  between sunscreens I do think people tend   to over focus on things like mineral versus  chemical really over analyzing their sunscreens really the best thing to do is to pick a  sunscreen that you like and apply a lot of it so they start by telling you to chuck  out last year's sunscreen which I think   is pretty good advice if your sunscreen  has been in last year's pool bag it's   probably been sitting around in the  heat and heat is bad for sunscreens sunscreens are emulsions that means they are  blends of water and oil-based ingredients which   are not happy together they're held in place  temporarily by emulsifiers but eventually they   want to separate if you have heat that gives them  enough energy to start separating faster sometimes   when you squirt out an old sunscreen you'll see  that it has separated and that means it's not   going to apply on on your skin the same way so  the advice is good but the reason is not as good they say the active compounds can  degrade and lose their effectiveness   this is true but most of the time it is  the separation and this does contribute   to the idea that mineral sunscreens  are more stable which is not really   true because those minerals are quite  dense they want to settle to the bottom but they don't quite say that  so I'm going to leave that as   half a myth in my rather subjective scoring system so the first mistake they list is concerned  about chemicals try a mineral alternative I   don't like the way they've worded  this because they are just kind of   accepting the premise that chemicals  are something to be concerned about   even though of course mineral sunscreens  contain chemicals everything is chemicals   but also chemical sunscreen specifically are  meant to be something to be concerned about so they sum up the situation with the FDA  and they say there's no evidence of harm   but then they end with still if you're  concerned there are options to avoid   these compounds I do like that they're  highlighting there are options if you   are concerned but they're kind of both  sides-ing this as a media outlet I think   their role is to get to the truth show the  scientific consensus which is they are safe and the FDA actually has a quiz on their  site one of the questions is actually a   recent FDA study showed that some sunscreen  ingredients are absorbed into the body and   they give you four options for what  you should do the correct option is   I should continue to use sunscreen  as directed evidence of absorption   doesn't mean these ingredients aren't  safe it just means more data is needed at the time those studies were published the FDA   also said you didn't have to  avoid particular ingredients so as expected they have the whole thing  about physical sunscreens physically   blocking UV light which is not true but  then they add that zinc oxide and titanium   dioxide are much safer than chemical  sunscreens because they're so inert inert means that they don't react but that's  not why they're safer they're safer because   their particles are huge and can't get through  the skin very far this is actually how the newer   chemical sunscreens are designed zinc oxide and  titanium dioxide are not inert a lot of the time   they get coated before they get put into a  sunscreen to make like a physical barrier   between those particles and the rest of the  sunscreen because they mess up the formulation and this inert concept is linked to the idea  that chemical sunscreens have to react with   skin to work NPR has that in another sunscreen  article that's linked from this article this   leads to other myths like chemical sunscreens  take 20 minutes to work or they have to be   applied to bare skin both of which are not true  they work immediately you can put some chemical   sunscreen on a piece of paper shine a UV light  on it and you can see that it is blocking the UV they make some points about why mineral  sunscreens are better they're less likely   to irritate which I guess is fair  and there are newer ones which are   more cosmetically elegant again  I think that's fair but this one unlike chemical sunscreens these mineral based  sun blocks can stay on the surface of skin and   act as a shield or barrier to deflect sunlight  chemical sunscreens also almost completely stay on   the surface they don't go past the top few layers  of skin which are dead except in tiny quantities again I think this comes from that  word absorb as well as absorbing   UV people have confused that with  absorbing into skin and again we   have a link to that NOAA page on  sunscreens destroying coral reefs now here is another myth that I see a lot a sunscreen with an SPF sun protection  factor of 15 blocks about 93% of UV   rays when you bump that off to SPF 30  you're blocking about 97% higher than   that you're not getting a lot more sun protection this is not a good way of looking  at it for a few different reasons you can look at what gets blocked versus  what gets in so you can say 93% versus 97%   or you can say seven percent gets  in versus three percent gets in what gets in makes more sense because that  is what impacts you it only matters if it   does and starts interacting with stuff inside  your body that means that SPF 15 is letting   in about twice as many UV photons which  means you have double the chance of damage the second part of this is that 97% only  happens if you apply it perfectly exactly   two milligrams per square centimeter  and you apply it perfectly evenly over   your entire skin which is not going to  happen most people don't apply enough   they apply less than half that amount which  means you get half of the protection plus   even us sunscreen nerds are not going to  apply perfectly evenly to all of our skin but when you're looking at what gets in that still  scales with protection so SPF 30 will always let   in half as much UV as SPF 15 if you apply the same  amount you will always get double the protection so this leads into this other aspect which  is there's no point going above SPF 30 but   this isn't true in practice because  of all this stuff we've just talked   about there are studies where people  applied SPF 100 or SPF 50 sunscreen   there were about half as many sunburns  with SPF 100 not just one percent less this is actually why SPF ratings are  designed the way they are you are not   meant to overthink that number there's  a paper from some sunscreen scientists   trying to get people to stop saying this 97%  thing but the AAD still has it on their website I do agree with this bit of skimping on  sunscreen is probably a bigger mistake   than not going above SPF 30 but the  amounts they recommend are not correct the recommendations for sunscreen  amounts are based on two milligrams   per square centimeter which is what you  need to get that SPF on the label for   the average adult it's pretty much agreed  that it will be 35 mL for your entire body there are a bunch of papers calculating  how much you should be applying and then   translating it to rough amounts that are easy  to remember that's where all this shotglass and   teaspoon stuff comes from there's even  a paper where they suggest a beer cap now the problem with all of these guidelines  is that they are rough and the more people   talk about them on the Internet the more  it spreads it gets rougher and rougher on top of that there is this sort of like  imperial versus metric issue the size of a   shot glass is not standard around the world  in Australia it is 30 mL in the US it is 30   to 44 mLs in Romania it is 100 mLs so one ounce  is closer to the right amount than 1.5 ounces now for the face one of the original  papers where they suggest this teaspoon   thing they actually calculated three mL  which is a bit over half a teaspoon for   the face and neck this has been further  approximated by different places like the   Australian Cancer Council they recommend  one teaspoon for face and neck and ears a lot of people have also measured how big  their face is a quarter teaspoon for just   your face is actually a pretty generous  estimate already so one teaspoon is just   too much that is four times as much and  most people's faces don't even need that   full quarter teaspoon for my face this teaspoon  would be six and a half times too much it just   isn't really achievable and I think when  you give people such an unachievable goal   it's just really discouraging you just end up  thinking sunscreen isn't going to work unless   it's dripping off your face and that's not  worth it so you may as well just not bother they have some good advice here they say  spray sunscreens are risky which is true   they say SPF doesn't tell you about time and  you still need to reapply sunscreen they have   the correct explanation for why you need to  reapply because they wear off especially if   you're swimming or sweating they mention that  you still can get sunburned on a cloudy day   which is true and they say don't keep your  sunscreen in a hot place very good advice layering sunscreen with hats clothing  and sunglasses this is great advice I   have some videos on how to choose sun protective  clothing and how much protection you get with hats they also mentioned these UV stickers which tell  you when it's time to reapply sunscreen which is   the correct use of them I've seen a lot of  people on social media using them to test   sunscreens which doesn't actually work it's just  meant to be a cute way of reminding you to reapply now this next part is a bit of an issue I've  seen this in a bunch of articles lately it's   this idea that people with black skin still need  to use sunscreen to prevent skin cancer there's   a research dermatologist who's done a lot of  work on this topic his name is Ade Adamson   he gave a talk at the sunscreen e-summit I  hosted with Jen of the Eco well last year he has analyzed lots of different types  of data and they all show that there   is no correlation between sun exposure and  skin cancer in black skin for example there   is no increase in skin cancer in black  skin when you go to towards the equator now it is true that black people  do still get melanoma and not   in sun exposed areas but it isn't  because there's less melanin there a lot of people mention Bob Marley and how he died  of a melanoma under his toenail but that was an   acral melanoma which is not associated with sun  exposure even in white skin toenails are actually   excellent sunscreen they block all of UV and  they only let in about 0.5 to 2.5 percent of UVA there is a concern with people with black skin  they tend to have lower skin cancer survival   rates because they tend to be detected  later and this is because of systemic   issues black people are less likely to go to  the dermatologist and melanomas don't look   the same on dark skin so a lot of doctors  can't spot them because of lack of training so the message that black people can  still get skin cancer is helpful but   then linking it to sun exposure linking it  to not wearing enough sunscreen is just not   right this is the wrong solution it  doesn't really help and it sort of   misallocates your resources whether that's  attention or investment in public health there are other reasons for black people  to wear sunscreen it prevents wrinkles   it prevents hyperpigmentation which  is how dark skin tends to age and it   prevents sunburn but skin cancer  is not a good reason to wear it there's this Washington Post article recently  where they had Dr Adamson talking about his   research and then a bunch of other dermatologists  saying people with black skin still need to wear   sunscreen and they presented both sides  as equal but this is just not how science   works it's not a popular vote again it's  about the consensus of relevant experts and   Dr Adamson is much more relevant than other  dermatologists here he's done that research   and scientific consensus isn't just like an  opinion you need the scientists to look at   and understand the same data and come to  a conclusion that makes scientific sense the next article is from the mirror doctor  explains what SPF number on sunscreen really   means and how often to reapply so the  first thing they talk about after all   the fluff is what does SPF mean and they  say SPF refers to the amount of time you   can stay day out in the sun without burning  so with SPF 50 you can stay out in the sun   50 times longer without burning than you  could have if you didn't have sunscreen on this myth is really common  and the reason it doesn't   work is because the sun's intensity changes a lot in SPF testing time works because the lamp gives  out a constant amount of UV so the UV dose that   you're getting how much is getting into your  skin is directly proportional to how long that   lamp has been on but this doesn't work in the sun  and it definitely doesn't work with higher SPF in the middle of the day in summer fair  skin burns in about 10 minutes and so SPF   50 50 times longer that's 500 minutes which  is more than eight hours your sunscreen is   not going to stay on your skin in an even film  for eight hours you're going to have to reapply   it because it will start clumping up it will  start sweating off so a better definition is   really just this it's a measure of how well  the sunscreen protects you from getting burnt there is another myth here which is that  SPF is just to do with the effect of UVB   it isn't there's also some contribution  to burning from UVA if you blocked out   all the UVB and led in all the UVA  you would only get SPF of around 11 on its own it's not the worst myth but it is  linked to another myth which is mentioned here UVA rays from the sun are the  ones that cause the DNA damage it's actually almost completely the other  way around UVB damages DNA directly DNA   will actually absorb UVB and kind of explode  DNA is actually transparent to UVA UVA will   interact with other things and form free  radicals which then indirectly damage DNA the reason I think this myth exists is  because we knew about UVB being bad for   ages but we didn't discover uva's damage  for quite a long time so there's this   misconception that UVA is more dangerous when  in reality it's just been previously underrated now there is one good thing about UVB and that is  it helps with vitamin D production so this myth   has led to a lot of people asking why don't we  just have UVA sunscreens that let in all the UVB   why don't we just look for the highest  UVA protection I don't care about SPF   but you should care about SPF because DNA damage again there's this idea that how much  sunscreen you apply is more important   than SPF I don't really agree I think they  are both important if you have lower SPF   you'll need to apply more and vice versa but  that is really just a difference of opinion this one is a common myth I've been seeing  in the news for chemical sunscreens you   need to reapply every two to three  hours as it degrades in sunshine and   becomes less effective mineral sunscreens  only need to be reapplied after swimming   towelling off or rubbing it off this is  incorrect and actually quite dangerous the reason you need to reapply sunscreen is  not because the chemicals are decomposing   it's because the sunscreen film clumps up on  your skin because you have this film sitting   on your skin you have sweat you have trans  epidermal water loss water is just evaporating   out of your skin you have oil coming out  from below your skin is moving around that   does not want to stay as a nice even complete  film once you have water and oil punching   holes in the film from below you're not  going to have protection in that gap if you look on the back of a mineral  sunscreen it will tell you to reapply   every two hours as well as during  these times after swimming toweling etc mineral sunscreens can in fact last less  long on the skin because they are chunky   chemical sunscreens can absorb into those  top layers and that kind of keeps it in   place but mineral sunscreens just sit  on top of your skin in those particles   and they tend to move around and go  into furrows so definitely reapply   your mineral sunscreen just like you  would reapply a chemical sunscreen this bit is correct even if it says  the sunscreen is water resistant you   still need to reapply after swimming  that water resistant rating is based   on people sitting still in a tub of water  you're probably going to be moving around   a lot more in the water which will  make that sunscreen wear off faster this next bit moisturizer foundation  with SPF isn't sufficient I agree with   the foundation but not with the  moisturizer the way a moisturizer   with SPF and a sunscreen are formulated  are the same whether the product gets   sold as sunscreen or a moisturizer is just  based on marketing not based on what it does so as long as you apply the same amount  like quarter teaspoon to just your face   you will get the same protection there  are studies that compared how much of a   sunscreen people applied and how much of an  SPF moisturizer and they found that the SPF   moisturizer wasn't applied as much but these  are generally the SPF moisturizers that come   in jars they're really not representative  of what's on the market there are a lot of   SPF rated moisturizers which could have very  well just had the word sunscreen on them in   Australia there's a bunch of formulas that are  really similar they have the same percentages   of the active ingredients and sometimes they're  called SPF moisturizers sometimes they're called   sunscreens so I would judge just based on texture  and not on what word they used on the packaging this is also probably not the best order putting  sunscreen and then moisturizer there are a couple   of studies that found that if you put the  moisturizer on after sunscreen then it kind   of works like a cleansing oil the film just gets  messed up because when you apply a moisturizer you   rub it in general if you've put on the sunscreen  layer you just want to disturb it as little as   possible so putting the moisturizer on underneath  is a better idea even better would be if you just   use a moisturizing sunscreen or an SPF moisturizer  just have both of them in the one product our next article is from Vox it's called  seven burning questions about sunscreens   answered the subtitle is yes you  need to wear it and the start of   the article talks about things like how  sunscreen is non-negotiable regardless of   the weather or your skin type  any dermatologist will say so one thing that's interesting is that  this seems to be only the consensus for   US dermatologists even in Australia with  our level of sun our official guidelines   say you only need to wear sunscreen  if the UV index is three or above now if you're into skincare I  think you should wear it every   day because so many skin concerns  are made worse by UV but from a   skin cancer perspective I really don't  think this is supported by the evidence and again we have this myth regular sunscreen  use can lower your risk of skin cancers both   among lighter-skinned people who are more  susceptible to skin cancer and people of   color who are more likely to die from  skin cancer due to a delay in detection again that last bit about delay in  detection is correct but there is   no evidence that regular sunscreen use  will lower the risk of skin cancer in   people with dark skin and this also extends  a bit to other people of color too the link   between sun exposure and skin cancer is  just a lot weaker than for white people now let's go on to these actual burning  questions again we see this misconception   UVA rays penetrate the skin more deeply that part  is true but greater contributor to skin cancer   is not it is really well established  that UVB is the greater contributor this is kind of like suggesting a myth but  they don't really quite say it UVA rays are   aging rays there's this common idea that UVA  a stands for aging b stands for burning but   that's not true both of them contribute to both  I already talked about how short wavelength UVA   contributes to burning UVB also contributes  to aging UVB actually directly contributes to   age spots by messing up the DNA of melanocytes  those cells that produce melanin at the bottom   of their epidermis but picking a sunscreen that  protects against both UVA and B is good advice now this is a good point mineral sunscreens  aren't natural they get processed massively   before they go into a product because you  need to get rid of things like contaminants   but they do have this myth mineral sunscreens  work by creating a barrier on the skin that   reflects UV rays and they mention this  related myth chemical sunscreens get   absorbed into the skin and help create chemical  reactions that lead to repelling the UV rays there's no chemical reaction involved in  absorbing UV if the chemical sunscreen   undergoes a reaction that is a bad thing it  means it's not photostable it's going to break   down what happens is the electrons absorb the UV  and they get more energetic but the bonds don't   actually change again if you want more info on  that check out my video on how sunscreens work there's pros and cons to each type that is true  regardless of what type of sunscreen you prefer   make sure it's water and sweat resistant I  think water and sweat resistance is good but   it's not really necessary I think for an  everyday sunscreen that you're wearing to   the office water resistant sunscreens still  tend to be pretty uncomfortable because they   form a really strong film that doesn't move as  much there's no standard for sweat resistance   anywhere so a lot of the time you won't see this  on sunscreens and even if you do it's hard to tell   what it means like how they tested it unless the  company literally tells you exactly what they did next they go through some of the pros and cons  of chemical versus mineral sunscreens and these   are pretty good ones it is mostly about what you  prefer I like that they mentioned fragrance in   the middle of this because that is an ingredient  that some people react to but it's kind of weird   how they kind of say it is only a concern for  chemical sunscreens later on they do mention   looking for a fragrance-free mineral sunscreen  though so maybe that was just awkward wording they have this bit on how much should  I spend on sunscreen and yeah you don't   have to buy anything expensive or fancy this  bit with tints not materially changing the   efficacy of the sunscreen I half agree  with this if you're just talking about   SPF then that's true the SPF is what it  says on the package but that tint comes   from iron oxide which does help with darker  skin if you have pigmentation problems iron   oxide can absorb blue light which can  lead to longer lasting pigment changes how much SPF do I need they have the SPF  definition with time so again that's not   quite correct because the sun changes  and again they have this thing with how   going above SPF 30 is not going to give you  much additional protection which is not true they say apply sunscreen 30 minutes  before going outside that's probably   overkill usually the recommendation  is 15 to 20 minutes and that's just   to let it dry down form a complete film not  rub off and also to make sure you don't go   into the sun and get a whole bunch of sun  exposure before you get the sunscreen on the best sunscreen option is one that  you'll readily use that is correct   having a spray is better than nothing but  this bit reapply every two to four hours   if you're in the sun that is not enough  pretty much every recommendation if you're   spending time outdoors is reapply every  two hours or perhaps even more frequently I have seen this myth a few times times on  Australian websites and it is to do with the   four hour water resistance rating but this  is not an Australian article an Australian   four hour water resistant sunscreased will  still say to reapply every two hours because   of that film wearing off honestly I  think they should change that water   resistance rating to a different name  from four hours it's kind of misleading wear sunscreen on your face and neck every day  as UV rays can penetrate windows in your home   and car I don't think this is really necessary  it depends on what your home is like I have a   video on working out whether or not you need to  wear indoor sunscreen in the car I think you do   because you have so much window space but in  your home if you're not sitting directly in   the sun if you're quite far away from the  window you probably don't need sunscreen now this bit French and Korean sunscreens versus  American ones there is this idea I see a lot   online still which is Korean sunscreens are less  reliable than ones from the US and I completely   disagree the article says a few years ago there  were some Korean sunscreens that a company had   tested by an independent laboratory and it did  not perform up to the label claim of the SPF this issue is really not limited to  Korea I've talked about it before in   another video there are lots of consumer  magazines that do independent SPF testing   on sunscreens they've purchased  and published the results Consumer   Reports Which? Choice Consumer NZ and  every year there are a bunch that fail part of this is because SPF testing is  a biological test and there is usually   more variation with that so there's  always been lots of variation between   different SPF testing labs it depends  on the country what sorts of people are   coming in and getting their skin tested  who's looking at when the skin goes pink but some of them do fall short by quite  a lot and it does feel weird to single   out Korea when the biggest cause  of these fails is probably the US the biggest sunscreen testing scandal that's ever   happened was with AMA Laboratories  in the US it's on the FDA website this lab was essentially committing  fraud for 30 years from 1987 until 2017 for SPF testing you need to have a certain  number of people you're testing on and they just   pretended they had more people they just like  made up numbers so this means they could really   speed up testing and they could also charge  a lot less so lots and lots of brands used   them there's now even a special note in the  Australian regulations where it says if you   got your sunscreens tested by this lab you  need to have new tests done by some date with the Korean sunscreens Odile Monod has  a video on that the issue seems to be they   change from a tinted sunscreen to untinted  without retesting it and this is allowed in   a lot of places around the world in Korea this  loophole seems to be fixed now and this is one   really good thing about Korean regulators  they are very quick to deal with problems   so I don't think this problem is really  relevant to Korean sunscreens anymore but sunscreens do fail testing all the time  including from the brands mentioned here and here are my rankings the longer  the article the more myths so I also   calculated it as words per myth like a  measurement of myth sparseness and the   longer articles ended up doing better  maybe because they were more padded out I also counted which myths came up the  most no surprise our grandpa myth topped   it I made this sunscreen myth bingo card a  while back the stuff on the right is mostly   crunchy social media myths so I didn't  really expect to do that well there but   the ones on the left are the ones I've seen  from more trusted sources decent hit rate I did not expect these two myths  to come up as much as they did so overall the myths in these articles aren't  that bad but it is really frustrating to see   these come up again year after year and still  not get corrected it'll be really nice to see   a better hit rate over the years maybe  I'll just repeat this exercise every year I did have a couple of other articles from  Bloomberg and Reader's Digest which had really   fear-mongering myths about the toxic effects  of sunscreen which I couldn't really fit into   this video because I would have to go into a lot  more detail I'll probably talk about those soon but yeah I hope you found this interesting  in the meantime the most important things   for finding a sunscreen look for a  sunscreen that's protective enough   for whatever activity you're doing these  are the three labels you're looking for if   you're doing something really sweat heavy  then go for the maximum for all of these second thing you're looking for is  the sunscreen that you enjoy enough   to wear every day this includes things like  texture whether it irritates your skin even   whether or not it fits in your budget  if you have a sunscreen that's really   expensive that you skimp on that is not  good value if you have a sunscreen that   was really cheap that you don't enjoy and  you never use that is also not good value see you next time there is a 50  50 chance it'll be about sunscreen