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How much sunscreen & how often?| Dr Dray

Hey guys! Today I am answering your questions about how much sunscreen to apply & how often to apply sunscreen. Do you need to wash your face before? Do you need to wear it inside? Do you need to reapply it when you are inside? How often?

Well hey guys in today’s video i’m going to talk about how much sunscreen you should be applying i get tons of questions about the nuances of applying sunscreen so i’m gonna try and tackle several common questions that i get about this and the first one is how much sunscreen to apply this is debated all over the internet one ounce of sunscreen equivalent of a shot

Glass to the entire body but how does that that doesn’t really help you in your day-to-day life when you’re covered up mostly and you just need to be protecting your face maybe your arms like it becomes very confusing and i will insert an infographic here so you can get a sense of about roughly the amount of sunscreen per body site like for example anywhere from

You’ll see anywhere from a third of a teaspoon to a full teaspoon recommended for the head and neck it’s not it’s not an exact science and obviously it varies depending on how how large you are you know just because body surface area differs quite a bit so it varies a lot and rather than getting hung up on this teaspoon amount it’s you know kind of shoot for that

But honestly what the studies show there was a linear relationship between the time spent and the amount used so the longer you spend the more likely you are to get to the amount that you need make sure you focus on getting it around your eyes to the sides of your face out to here where your ear is and of course all around your ear and the sides of the neck the

Back of the neck don’t skip any of these areas and so the more time you spend putting it on the less likely you are to skip those areas not putting it on in a hurried manner also reduces the issue of pilling and buying that can happen with sunscreens if you just put big globs on and put it on very quickly done that can lead to a lot of pilling and buying because

Basically you’re not you know you’re not really spreading it out onto the skin and so as the film is forming under that big glob the rest of the sunscreen that’s sitting on top of that film kind of starts to peel off and then it takes the film underneath off with it and you get balling and pilling so go really slowly and just make sure that you spread it out onto

The surface of the skin after you apply that first layer allow it to absorb and dry and then put another layer on this also will increase the protection that you get from the sunscreen with one application you actually miss about 20% of the surface area with just one layer this is why i layer sunscreen all the time and i often get questions like why am i doing that

And the reason is because there are skip areas in between now how often to apply in order for sunscreen to be effective it has to be reapplied regardless of what activities you’re doing or what you have planned for the day the reason for this is that we produce oils on our skin through our pores we sweat even if you don’t feel sweaty there is a little bit of ekron

Sweat coming out of your skin on an ongoing basis and that starts to break down that film and starts to erode the protection of the sunscreen so it has to be reapplied throughout the day how often if you are outside outdoors sunscreen has to be reapplied every two hours at least and honestly if you definitely definitely if you were outside of the beach and whatnot

Being very active i would say every 90 minutes because you’re sweating a lot more and it’s hot and everything and it’s coming off so yeah very very frequent that being said when you are outdoors that long and you’re starting to have to reapply that frequently that’s that’s a signal that you need to definitely bring in on other things seek shade cover up put on a

Hat definitely pull in all of the behaviors because if you are outside like you know in in a bikini for longer than 90 minutes and comes coming to town to reapply the sunscreen like you the sunscreen is really just just kind of helping a little bit you need other things you need other things if you are outside that long so that’s not now what about when you are

Indoors all day do you have to reapply absolutely again in order for it to to work it has to be reapplied but you don’t have to reapply it as frequently like every two hours thing my rule of thumb is when you are indoors throughout the all day reapply your sunscreen at least three times a day get at least three applications on throughout the day breakfast lunch

And dinner the reason for this is that a lot of uva comes through the window as just visible light which can drive hyperpigmentation but uva contributes to skin cancer risk as well as photo aging so you need to protect your skin from those rays even when you’re indoors so absolutely and i i say three times a day just you know it’s kind of something i’ve made up

For myself i find that it is doable to do like a breakfast lunch and dinner style application for days one you were exclusively indoors you can you can do more than that but you know if you don’t reapply when you’re indoors you’re still sweating it off and still coming off and as that uva comes through the window you’re getting exposure there there’s a classic

Image of a woman who sat who worked in an office by a window for many years and you can see the striking unilateral photoaging of her face on the side next to the window i mean it’s dramatic i’ll insert it here so you guys can see what about water resistant sunscreen okay you still have to reapply water-resistant sunscreen as well same rules apply to water-resistant

Sunscreen as non water-resistant sunscreen so you’d have a water-resistant sunscreen that’s water-resistant up to 40 minutes or that’s water-resistant up to 80 minutes basically what that means is that they perform the spf testing on human skin to determine how well the product will protect the skin from burning and after they do that they then submerge i think

It’s the arm actually it might be the back they actually submerge that skin in a whirlpool bath tub for 20 minutes and then they remove it let it air dry they put it in again for another 20 minutes and in the case of the water resistant up to 40 minutes sunscreens they reassess pf’ protection and if the protection is maintained then i get you waters the the labeling

Water resistant up to 40 minutes for 80 minutes they do more dogs basically but that doesn’t mean that it is waterproof basically if you go in the water it will still rub off but it’s not gonna wash off all at once and so it’s helpful and necessary for protecting your skin while you are underwater because guess what you can get burned in the water it’s more likely

Because it’s more it’s intensified by the water so you definitely need protect you definitely need to be with having sunscreen that stays on the skin while you were in the water but when you get out it doesn’t mean that the sunscreen is still good you have to reapply after you get out of the water and if you’re gonna be in the water for longer than longer than 40

Minutes i would say get out and reapply because it’s not gonna stay on there indefinitely while you were in the water when you’re not in the water the same rules apply reapply over two hours while you’re going to be outside for prolonged period of time and reapply the water resistant sunscreen at least three times a day if you’re wearing out inside because even

Though it’s water-resistant it doesn’t mean that it is oil and sweat resistant it doesn’t mean that you’re not losing that protection it’s a say for example you are outside for two hours you know you’re still losing that protection one nice thing about it though is that water-resistant in between application you have a greater the duration of protection is a little

Bit higher with water resistance so i really like water resistant sunscreens for that reason and i recommend them for everyday use do i need to wear sunscreen when the uv index is like two or really low and the answer is yes the uv index if you’re not familiar is a metric that captures the sun intensity in a way that gives you a measure of your risk of burning night

Day essentially what it is is a metric of uvb exposure uvb is a part of ultraviolet radiation from the sun that burns the skin so on a day where the uv index is low your risk of burn of your skin burning is much lower than when it’s higher but that metric does not capture uva uva is actually the majority of the ultraviolet radiation that comes down to the earth and

Reaches our skin and uva is what penetrates very deeply it destroys our collagen is responsible for a lot if not arguably the majority of photoaging as well as skin cancer risk it’s what comes in through window glass even when the uv index is low the uva is still there and still something you need to protect your skin from when you when you are indoors and when

You’re outdoors even when it’s cloudy out so definitely definitely wear the sunscreen regardless of the uv index the next one is how tips for applying sunscreen over a full face of makeup and i’m going to do a separate video on that for you guys so stay tuned for that i’ll give you guys some tips and strategies it may already be up i haven’t decided what order

I’m going to put them up but that would be the other one another common question that i get is why do you promote sunscreens that say spf 100 isn’t that like wrong you know we used to maintain that anything higher than like spf 50 was not like worth anybody’s time because its ability to protect you from a burn in testing and testing is is really no different like

An spf 50 sunscreen and sp have a hundred there when you when put on when put on test subjects this is key when put on test subjects at a density of two milligrams per centimeter square they’re virtually identical in terms of their ability to protect that that area from from sun induced burning but we have learned that in real real world use dot but that actually

Is not true that because consumers grossly under apply sunscreen they actually get better protection at the end using a sunscreen that has a higher spf simply due to the fact that they under apply a sunscreen so higher they get they end up getting closer to spf 30 or 40 with a higher spf just because they under apply a so ya higher is actually better at something

We’ve learned i think in my earlier sunscreen q&a is when i first started my channel i probably told you guys that higher made no difference but we we actually know that it does seem to make a difference in we’re all real world views some studies also suggest that possibly higher spf sunscreens might also afford better uva protection a major issue with sunscreens

In the united states is that they’re not required to quantify or disclose to what extent their product protects you from uva spf is giving you giving you a sense of how well protect you from a burn but it gives you no sense how well it will protect you from those aging rays that penetrate very deeply and the reason for this is that there’s really no agreed-upon

Assay for measuring that other countries each have chosen to quantify that outside of the us and do their own testing of that and report it in their own ways that’s why you see some sunscreens are labeled with pa ratings and and whatnot so you know every every area of the world they have they have decided of their own you know what what they want to do for uva the

U.s. is is the least least thorough and they just do a pass/fail basically the sunscreen has to protect against uv eye but you know uva is a pretty big part of the ultraviolet radiation spectrum so to what extent you’ll find an american sunscreens u.s. sunscreens there is likely tremendous variability so you never really know that but kind of a back backhanded

Way to to get around that is to choose sunscreens that have a higher spf it seems so yeah that’s what i can tell you about that okay your skin from uva is really important so yeah the other thing i would say is you guys ask me people will ask me this all the time and i don’t know where you’re coming from what countries of the world you are but people will try and

Ask me how one sunscreen that i’m talking about compares to another sunscreen in terms of its ability to protect you from uva particularly people who live in areas of the world where you have uva rating systems you want me to cross compare i cannot do that i cannot do that there you can’t figure out how how well sunscreen is going to protect against uva based on

Ingredients like i can’t come up with a pa rating off the top of my head like i just can’t so people ask me that i have no way of knowing it seems as a higher spf definite gives better at uva protection but i can’t i can’t give you a pa rating based on that another question i get a lot is should we wash our face before reapplying sunscreen heck no that defeats the

Purpose there is still some residual protection left on the prior application your you know your you don’t want to wash that off and also the more like if you wash your face that many times a day you’re gonna have a terrible irritant contact dermatitis and and you know it’s not gonna be a good thing and i can flare acne as well so no don’t wash your face in between

Reapplication like before reapplying and likewise another similar type of question is well i don’t care for the shininess of the sunscreens so i blow i use a blotting paper is that okay no your blotting off the sunscreen when you do that instead if you don’t like the shininess an alternative is to use a mineral sunscreen powder on to to to kind of mattify not

Shininess because at least where you touch with the powder you’re putting down sunscreen as opposed to just wicking it off and not replacing it so that would be my recommendation for the shininess but no the blotting paper thing know that that you can’t do when it comes to applying sunscreen wash your hands before you apply and while i’m shown in my videos before

Me applying sunscreen in the car like you know obviously that’s not ideal now in the current situation we’re trying to really be conscientious of our hand hygiene but yeah i mean obviously that you know wash your hands before you put it on people also verbalize a lot of concern about reapplying sunscreen that you’re kind of sandwich bacteria and dirt in between

The layers there’s no reason for you to worry about that you know there’s no study out there that i can cite that quantifies dirt and bacteria within the pore lining before and after numerous sunscreen applications so i don’t have a scientific reference just trust me like it’s fine that being said this ties into the next set of questions you do need to wash your

Face at the end of the day or body if you’ve been applying sunscreen to the body as you should if the if you’re if you’re wearing shorts definitely apply to your legs and arms if you’re wearing short sleeves but take it off at the end of the day and the best way to do that is to actually use an oil-based cleanser particularly for the water resistant sunscreens use

An oil-based cleanser to break up that film and then step in the shower and wash wash-off the broken up sunscreen layer oily residue with there’s a gentle non stop cleanser but there was a recent little paper that actually showed this was the best way to remove it because one issue that can happen for people especially with people with acne it’s said they don’t

Adequately remove the film and that’s you know because it’s intended to really stick on your skin so it can stay on there and you know with makeup and things and start mixing and irritating around the pores so definitely wash it off at the end of the day and using an oil-based cleanser is the best way to do that so those are my tips about sunscreen application and

Kind of addressing some of the common questions and concerns that i get i hope this video is helpful to you guys if you liked it give it a thumbs up share it with your friends and as always don’t forget sunscreen and subscribe i’ll talk to you guys tomorrow you

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How much sunscreen & how often?| Dr Dray By Dr Dray