On Health with Houston Methodist

Blue Light: What Is It & Should You Use Blocking Glasses?

• Houston Methodist • Season 8 • Episode 7

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The blue light emitting from your screen as you read this has become a bit of a bogeyman, allegedly responsible for eye strain, headaches, poor sleep and much more. Enter blue light-blocking glasses, also called blue light glasses or blue light-filtering glasses. Advocates of blue light glasses claim these lenses can absorb or filter the short wavelengths of blue light produced by our devices, which in turn improves sleep, vision and even focus and productivity. In this episode, we explore blue light and whether specialized eyewear is the answer to its possible harms.   

Expert: Dr. Amina Malik, Ophthalmic Plastic and Reconstructive Surgeon

Interviewer: Zach Moore

Notable topics covered:

  • What exactly is blue light, and is it a problem?
  • The biggest source of blue light (it’s not your phone or TV)
  • Does blue light affect your circadian rhythm?
  • Who is more at-risk for blue light exposure
  • Rose-tinted glasses are real — what are they used for?
  • The 20-20-20 rule and other tried-and-true tips to help eye strain
  • It’s not just the light: Why you should limit screens before bed
  • How to choose the right sunglasses to protect your eyes
  • What eye color has to do with light sensitivity, skin cancer

If you enjoy these kinds of conversations, be sure to subscribe. And for more topics like this, visit our blog at houstonmethodist.org/blog.

<b>♪ ♪</b>

ZACH MOORE:

Welcome to On Health with Houston Methodist. I'm Zach Moore. I'm a photographer and editor here, and I'm also a longtime podcaster.

KATIE MCCALLUM:

I'm Katie McCallum, former researcher turned health writer, mostly writing for our blogs.

ZACH:

Now, Katie, neither of us are wearing glasses right now.

KATIE:

Uh-uh. ZACH: But sometimes we do. I would say usually I do, actually. I caught you off guard today, didn't I?[Laughter]

ZACH:

When you do though, are they blue light blocking glasses? KATIE: They are not. Okay.

KATIE:

They have some -- I paid for the anti-reflective coating.

ZACH:

Okay.

KATIE:

But that's not blue light blocking, I don't think.

ZACH:

Well, we'll talk about it today.'Cause that's what we're talking about. Blue light blocking lenses, blue light blocking glasses. I have blue light blocking lenses.

KATIE:

When do you wear them? You're not wearing them right now.

ZACH:

No, I am fortunate enough where my eyesight is good enough where I don't need to wear glasses all the time. Like, my driver's license, I don't need to wear glasses and that sort of thing. But when I'm reading or I'm spending a long time long at, you know, computer screens which is, I think, like everybody's life now, always look at a screen, either it's a big screen or a small screen, or a handheld screen. When I'm doing that for long periods of time, I do wear the glasses. They do help me kinda -- I have a slight astigmatism, so it just makes things a little more in focus. And obviously, being a cameraperson, I need to be -- have things in focus. So, I like the freedom of not having to wear glasses all the time.

KATIE:

I don't have that freedom. I either have to wear glasses or contacts. I do think it's an option when I get my glasses made to put the blue light blocking coating on there. And I don't think I've ever done-- I know I've never done it.'Cause, you know, like, all these coatings add up pretty fast and I do get eye strain though. Which is where my, like, anti-reflective coating…

ZACH:

Okay.

KATIE:

Idea came from, and it does seem to help me. Should I also be adding on the blue light blocking coating?

ZACH:

Well, that is the question we're gonna talk about today.

KATIE:

Okay. Perfect.

ZACH:

And we talked to Dr. Amina Malik. She is the Director of Oculoplastic surgery here at Houston Methodist. Alright. Thanks so much for being on the podcast, Dr. Malik.

DR. AMINA MALIK:

Thanks for having me. Excited to be here.

ZACH:

We've really become a screen-centric culture, computer monitors, smart phones. We look at digital screens now more than ever, all day, every day. I read a stat recently that the average screen time is reaching 13 hours per day, which I use my phone a lot, but I don't even approach that, so I feel better about myself.[Laughter] But also that 94% of eye doctors are concerned about blue light exposure. So, all that to say blue light glasses are a relatively recent invention to respond to this, correct?

DR. MALIK:

Yeah, you're absolutely right that it has really taken off in the early 2000s with the emergence of smart phones and the technological world we're living in. But in reality, blue light glasses first emerged back in the 1960s, but again, didn't really take off in popularity until the number of hours per day that the average American is spending in front of their screen rose to the, kinda, scary levels we're at today.

ZACH:

Wow, 1960s. That surprises me. I would have thought, I don't know, the 90s maybe that's -- I guess then it was more about true daylight.

DR. MALIK:

Daylight and then also TVs, you know, like the screens, computer screens, one was IBMs' first computer.

ZACH:

Wow. I remember my mom used to have a blue light overlay to a monitor she used to put on it, you know. DR. MALIK: Oh, there you go. She was ahead of the time.[Laughter] That was the late 90s, so yeah. So, let's define a couple things. Let's define blue light first of all. When we say "blue light," what do we mean?

DR. MALIK:

Blue light is actually part of our visible light spectrum, so what the human eye can see. And it vibrates within the 380 to 500 nanometer range, so it has the shortest wavelength and the highest energy. And about one-third of all the visible light that we see is considered blue light. And so, where does this light come from? Well, sunlight is actually the most common source of blue light. It's the biggest source. But there are also several artificial sources of blue light

that we talked about:

fluorescent lights, LED TVs, computer monitors, smart phones, tablets. There are all sources of blue light.

ZACH:

Okay.

DR. MALIK:

And it plays an important role in our circadian rhythm. So, we know that exposure to blue light before bedtime could theoretically disrupt our sleep patterns because it affects when our bodies create melatonin. We know that interruption of the circadian rhythm can play a role in the development of other systemic diseases including diabetes, heart disease, cancer, sleep disorders, and it can also affect our cognitive function.

ZACH:

Now, let's define blue light glasses or blue light absorbing lenses. I've heard both terms. Is there a term you prefer or use more than one than the other?

DR. MALIK:

They all can work, but blue light glasses is the shortest so why not use that? Blue light glasses are just basic glasses, but what's special about them is that they have a coating over them that actually absorbs the blue light to prevent that blue light from them entering our eyes.

ZACH:

So, you went over a lot of the sources for blue light, obviously, the sun, screens, etcetera. Look, we're gonna be exposed to a lot of these things all day. Right? But why is blue light bad for our eyes, like at least an overexposure to it? Like, what's the level there where it's like,"oh, now you've had too much" or what --

DR. MALIK:

Sure. ZACH: Yeah, Let's go into that. So, again, our eyes are not very good at blocking blue light, which is why these glasses developed, and nearly all of the visible blue light that we're exposed to will pass through the front of the eye, which the clear front of the eye is called the cornea. It'll then pass through the lens, which is what eventually could turn into a cataract which could lead to vision problems down the road. And then the light reaches the back of the eye which is the retina. And those are the cells that really convert the light into the brain to process what we see and create those images. And when we have constant exposure to blue light over time, that could theoretically damage retinal cells and cause vision problems such as age-related macular degeneration. Can also contribute to the lens developing into cataracts. Could also theoretically lead to increased eye cancers and growths on the clear part of the eye. And as all of these conditions can worsen from light exposure. There was one study by the National Eye Institute that proved that children are more at risk than adults because their eyes tend to absorb more blue light from digital devices than adults. ZACH: Okay. So, obviously, there is a need to protect your eyes from blue light, especially overexposure to it. Now, to the laymen out there you see list of like, "oh, there's blue light absorbing lenses, and blue light glasses, reflective lenses." Like, what's the difference between those? So, anti-reflective lenses are really designed to just reduce glare and reflections on the surface of the lens which can improve our visual clarity. They achieve this by minimizing the amount of light that bounces off of the lens surface. And these anti-reflective coatings are often applied to both the front and the back of the lens. And again, they're beneficial to reduce eye strain and potentially improve your vision in various lighting conditions. Now, blue light absorbing lenses are different in that they're actually designed to filter out specific wavelengths of blue light, again, which are emitted by digital screens and other artificial light sources. And some of them can be tinted yellow, or amber, to sort of further enhance that filtering effect. And these can be really helpful for patients who wanna improve their sleep quality if they're spending all day in front of their screens. And some of these blue light blocking lenses are also infused with melanin which can filter out up to 98% of blue light. So, to summarize the difference, anti-reflective lenses reduce glare while blue light absorbing lenses filter out the blue light.

ZACH:

Are there any other kind of specialty glasses beyond those?

DR. MALIK:

There are conditions such as blepharospasm where patients can have uncontrolled blinking of the eyes. And there are special glasses called rose tinted glasses that can decrease blepharospasm, also because they can help filter out some of the light that could be potentially associated with that spasm. ZACH: Wow. I thought rose tinted glasses was just a phrase that people used, right? Like, "You're looking at this with rose tinted glasses." But that's a real thing. DR. MALIK: It is a real thing.

ZACH:

That's the most interesting fact I learned.[Laughter] We've touched on this a little bit already, but when should you use blue light glasses? Like, can you wear them all day and it's okay? Are there any potentially negative side effects?

DR. MALIK:

So, the amount of light actually coming from computers have never been demonstrated to actually cause eye disease in several studies. There was this study that was done by the National Library of Medicine and they didn't find any measurable UVA or UVB radiation that is emitted from computer screens. And the UV radiation is really the most harmful part of light. So, you know, the American Academy of Ophthalmology does not currently recommend the use of blue light glasses because of the lack of scientific evidence to prove that it decreases the incidence of these eye diseases. However, if you have a tough time sleeping, certainly you could try these. And I've not heard of any negative consequences from over wear of these types of glasses.

ZACH:

Okay. Wow. So, you know, we've talked about helping you sleep and making it more comfortable to, you know, read things on screens by minimizing glare, and brightness, and there's even talk about helping improve productivity and focus, right? But you're saying, like, the hard facts don't really lean one way or the other with blue light glasses, huh?

DR. MALIK:

Right. You know, several studies have shown that blue light blocking glasses don't improve symptoms of digital eyestrain. Again, there's not a lot of scientific evidence that suggests that blue light is actually damaging to our eyes.<i>♪ ♪</i>

ZACH:

Up after the break, more with Dr. Malik.

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ZACH:

I actually have blue light glasses because I work with screens a lot, you know. And there is one thing I've -- obviously, I've noticed, they're -- It's blocking out blue light, so it does -- You mentioned earlier a little bit too. It changes the color of what you're seeing. It's like yellowish tint to things which make sense'cause they're blocking blue light. But also, you know working in photo and video as I do, I shouldn't be color correcting things with these on. So, that's a tradeoff I have to make and I think I might, even for the next round especially after what you just told me, maybe I won't do the blue light blocking lenses.

DR. MALIK:

Well, anecdotally, do you feel like it makes you sleep better or any difference in terms of your sleep/wake cycle. ZACH: No. I -- Well, you know, it's just something you hear, right? People are like, "Oh, well, you look at screens a lot. Oh, well, you should get the blue light blocking lenses." I'm like, "Oh, of course." And you don't really think of it further. Well, again, I don't think it's gonna hurt anything by wearing them, but unfortunately, the scientific evidence does not back the efficacy of them at protecting our eyes. There was a systematic literature review of 17 randomized controlled trials that found that blue light filtering lenses may not necessarily attenuate symptoms of eyestrain. In addition, they found that there -- any potential effects on sleep quality were indeterminate. And this included trials reporting mixed outcomes among heterogeneous study populations. There was also no evidence from these randomized clinical trials relating to the outcomes of contrast sensitivity, color discrimination, glare, any retinal diseases, or serum melatonin levels, or overall patient visual satisfaction, kinda speaking to what you were noticing. So, I think there is a need for some future high-quality research to define more clearly what the effects of these blue light lenses are on our visual performance, our eye health, and sleep.

ZACH:

That is interesting because another fact you told me right off the top is that these have been around since the 60s, I would have thought maybe we would have had some tangible answers one way or the other by now, and we just don't, do we?

DR. MALIK:

Unfortunately, not currently.

ZACH:

Wow. Okay. Wow, you're really rocking my world view here with the --[Laughter]

DR. MALIK:

Sorry to create the waves.

ZACH:

But, you know, what can someone do to help with eyestrain, or sleep, or the things they're trying to help by getting blue light blocking lenses that may or may not work? What would you recommend in that case?

DR. MALIK:

So, for starters, for eyestrain, I mean, we all live in this digital world, so I think it's really important to follow some basic rules when we're gonna be spending extended periods of time in front of the screen. And you may have heard of the 20/20/20 rule as something really commonly preached by ophthalmologists. And so, this rule says that every 20 minutes that you're looking at a screen, take a break for 20 seconds and look at something 20 feet away. And this can really decrease the amount of strain and eye symptoms that one experiences. In addition, research has shown that we don't blink as much when we're in front of screens so it is reasonable to get a preservative-free artificial teardrop, and when you're gonna be in front of the screen for a prolonged period of time, put a drop in, you know, every hour or so to help keep the eyes moist and feeling refreshed. You can also just take manual breaks and remember to blink your eyes to give them a break. And then when it comes to sleep, you know, it's reasonable to put away your screens, your phones, your tablets for two to three hours before bedtime. Or if you do have to use your phone before going to bed, try to use the night mode which has a little bit of decreased contrast sensitivity that can help.

ZACH:

Okay, so that works. DR. MALIK: Mm-hmm. I was ready for you to tell me that doesn't work either.

DR. MALIK:

No, I think it's reasonable. I mean, again, I don't know that there's randomized clinical trials that have proven anything scientifically, but I do think that is something free and it's easy to do.

ZACH:

Okay. See, that is such a big ask to tell people,"Hey, don't look at your phone for three hours before you go to sleep." Because that's like --

DR. MALIK:

I don't think I could do it. As much as I want to.

ZACH:

But, that's like your -- part of your routine, right? You know, you gotta -- you check your websites, and your social medias, and then you set your alarm, and you scroll a little bit. And so, you know, you're -- I mean, realistically, I mean, what about, like, 30 minutes before you go to sleep?

DR. MALIK:

So, I mean, I feel like if you have to do it, yeah, alright, just kinda keep the night mode. Exactly. But we all have to be realistic, right? And so, I would just say to use that night mode on your screen and try to just minimize the amount that you're spending on the screen. And if you need to do it, maybe do it like an hour before you go to bed or 30 minutes before you go to bed just to kinda help that circadian rhythm.

ZACH:

Okay. You know and circling back to what you said a little bit earlier the 20/20/20 rule. Unfortunately, I think about when I'm, you know, working on my computer and I'm looking at a screen and then, you know, what do I do? I go from that screen to my smaller screen, my phone, 'cause that's what I look away to. So, that is doubly bad.

DR. MALIK:

Gotta set something beautiful 20 feet away to stare at every 20 minutes.

ZACH:

You know, it's like in the old days you see somebody have, like, a nice, big picture of their family on their desk or something like that, maybe do that.

DR. MALIK:

Alright. There you go.

ZACH:

I'll have to think about that, because that's just a bad habit. Right? I mean, we're so plugged in to our phones.

DR. MALIK:

We're all guilty of it.

ZACH:

It's like no matter where we are, it's like -- I -- It's -- If you're standing somewhere for too long -- and I'm just speaking for myself maybe. But like if I'm standing somewhere for too long, I'm like, "Oh, let me pull out my phone and check it." Like, maybe don't -- maybe just, you know, look around and enjoy the world around you.

DR. MALIK:

Live in the moment. Be present, right?

ZACH:

Yeah. Exactly. Exactly. So, you know, you mentioned UV protection before. Let's talk a little bit about sunglasses, right? Are there blue light blocking sunglasses specifically or the standard UV protection sunglasses do the job?

DR. MALIK:

So, when it comes to sunglasses, really the most important thing to look for are gonna be UV blocking sunglasses. Because again, UV is the most dangerous part of sunlight. And why is that? Well, it can affect the eye in myriad of ways, starting from the outside of the eye, the eyelid. You know, 5%-10% of all skin cancers occur on the eyelid. And that's not usually a very common place that people think to lather up with sunscreen. So, when we wear these UV blocking sunglasses, that's one layer of protection to avoid that sun damage around the lid to increase -- to potentially decrease your risk for eyelid skin cancers. And then delving a little bit into the deeper layers of the eye, UV light can be associated with pterygiums which are growths that occur on the clear part of the eye that can lead to irritation and discomfort. It can also be associated with eye cancers, macular degeneration, and cataracts. And these are all things that can, of course, lead to visual problems down the road. So, again, when it comes to buying those sunglasses, always look for the UV radiation. In addition, there are also UV hats that one can purchase. You know, they may not be the most fashion forward, but they will help with the UV blocking and protect your eyes even further. ZACH: I have seen the UV hats. I have a possibly a dumb question about UV sunglasses. Are there sunglasses that are not UV protected sunglasses? There sure are. ZACH: Okay. If you don't wanna spend a big buck, you could probably find some cheap ones that --

ZACH:

Yeah, like, the ones at the Dollar Store don't have --

DR. MALIK:

Exactly.

ZACH:

'Cause there's, you know, there's a sticker that I always find it really difficult to get off when I get sunglasses. It's on the front lens and it usually talks about the UV protection. And there's usually a number on there which I never pay attention to really. But what is, like, a number -- what should we look for when getting sunglasses for UV protection?

DR. MALIK:

Definitely an important label to read before you attempt to peel it off. So, you always wanna look for sunglasses that are labeled either 99, ideally, 100% blocking. This would indicate that they're blocking all the harmful UV rays up to 400 nanometers, and that's gonna cover both the UVA and the UVB, which again is gonna be the most important for protection. ZACH: Okay. No, that's good to know. I mean, I like wearing sunglasses. And, you know, when I forget my sunglasses, I can really tell. Like, I'm like, I find myself squinting and that sort of thing. And you have light eyes too and that patients who have light eyes tend to be even more light sensitive.

ZACH:

You're saying because I have lighter eyes, I'm more susceptible to these rays.

DR. MALIK:

Yes, so unfortunately, patients who have lighter eye colors, blue or green, are at slightly increased risk for certain types of skin cancers because there is less protection from the UV rays. They have decreased melanin to protect from that and lead to an increased risk of skin cancers.

ZACH:

Wow. Okay, 'cause you think about your skin obviously, but you don't -- I never thought about my actual eyeball as being, you know, more or less susceptible.

DR. MALIK:

Yep. There is higher rates of basal cell cancers, melanoma, squamous cell carcinomas. Those are all associated with higher risks in patients with lighter color eyes, unfortunately.

ZACH:

Okay. Wow, that's good to know. I'm glad I wear sunglasses all the time now. Like, it's not just a fashion statement, people. It's health safety. DR. MALIK: There you go. Alright. Well, you know, we've talked a lot about alternatives to blue light lenses, because apparently, they're not all they're cracked up to be. So, are there any other strategies or anything else you'd like to share about protecting your eyes from blue light?

DR. MALIK:

I think one of the most important things we can do is just minimize the amount of time in the screen. Or if we have to be in front of the screen, like, some of us, then we just need to remember to take those breaks and give your eyes a chance to reset.

ZACH:

The 20/20/20 rule. DR. MALIK: That's it. I'm gonna start trying that.

DR. MALIK:

Perfect.

ZACH:

Stop looking at my phone when I look away from my screen, which is worse. There's no escape from the blue light, though. I mean, you go inside, you're looking at screens, you go outside, there's the sun. Like…

DR. MALIK:

There you go. But you got sunglasses you can put on.

ZACH:

So, you can wear sunglasses inside too is what you're saying? DR. MALIK: You could.[Laughing] In fact, my mom does that. Doctor approved, everybody. Sunglasses inside. Next time you see me, I'll be wearing sunglasses inside. Well…

DR. MALIK:

You'll look really cool too.

ZACH:

I think so too. Thank you. Well, thank you so much for this conversation. Again, you have rocked my world view about the blue light glasses. When it comes time to get another pair of glasses, I probably won't do the blue light lenses. But I think it's important to, again, say, look, they're not bad for you.

DR. MALIK:

Right, so if you wanna do it, go right ahead.

ZACH:

There's just really no tangible way that --

DR. MALIK:

There's no data to support that you're really helping anything. ZACH: Well, there you have it. So, again thank you so much Dr. Malik. I appreciate this conversation. Very informative. Thank you for being on the podcast. My pleasure. Thanks for having me.

KATIE:

So, Zach, you seemed pretty taken aback by how this conversation went. ZACH: My life is a lie. I -- You know, you hear about blue light blocking lenses and you're like,"That sounds like a good idea." You're always hearing about,"Turn your blue light filter on your phone," or "put this blue light filter on your monitor." You hear these things all the time. And the way blue light lenses are sold to you is like this is gonna help you. KATIE: Yeah.

ZACH:

Well, yeah, abso -- sign me up. I wanna be helped. But it's not true. There's no scientific evidence that it really helps you. Now, they're not gonna hurt you, as we talked about.

KATIE:

There is a point in y'all's conversation where -- so my guilty pleasure, and when I know I get the most blue light is when I'm really stressed at work, you know, I'm staring at my screen all day, all day, all day, and then, like my way to de-stress is to play Candy Crush. And like, I'll play for like three or four hours straight. And then, the next day, I will wake up with a headache, my eyes will be hurting. So, while y'all were talking, I was like,"Oh, maybe I'll just play Candy Crush with my blue light blocking glasses on." But, no. Then actually, it turns out those don't help either, and I probably just need to not play Candy Crush for four hours.

ZACH:

Well, you need to do the 20/20/20 rule.

KATIE:

I loved that. You know what I w -- when you guys were talking, what I thought of was, you know how your smart watch -- or maybe not yours,'cause yours isn't like mine. My smart watch, at the end of the hour, will be like -- if I haven't stood up, it will send me like a prompt, like,"Hey, stand up and walk around." I want a like,"Hey, take a break. Look at something for 20 seconds that's 20 feet away." I could use that, because I will not think to do that on my own.

ZACH:

No, it's so true, because I'll be, you know, working on something on my screens…

KATIE:

Oh yeah. You're locked in.

ZACH:

And then I'll go to my other screen and, like, for a break doesn't make any sense.

KATIE:

I laughed when you said that actually.

ZACH:

It doesn't make sense. KATIE: Yeah. Your break is, like, to check Instagram or something which more blue light. Well, there are a lot of strategies around this, right? I mean, one strate -- Is not even related to blue light filters or anything, but just to get you moving. The same logic applies, like, just constantly be drinking water all day, right? Keeps you hydrated. When you run out of water, you have to get up and refill your glass, that's sort of thing, right? So, I mean, that's what I do that hopefully helps a few of these things maybe. Because if I'm going in the refrigerator to get my water, I'm not staring at a screen. KATIE: Yeah, no.'Cause my refrigerator doesn't have a screen yet, right? KATIE: Well, but they do. I mean, you could buy one that does. I start to understand why people reject technology now the more… KATIE: Yeah. The more research they're doing on these things. But no, I was kinda shocked. KATIE: Yeah. I was shocked by -- Or alarmed by the fact that kids absorb blue light even easier. And in, you know, in today's, kinda, times kids are on devices way younger than -- Constantly.

KATIE:

Way younger than we were growing up, and then they're, you know, they're on them earlier in age, they're on them probably longer and more and more as the years go on. Just like flooding their eyeballs with blue light. I mean, I wouldn't be surprised if at some point there is more research into blue light blocking technology. But yeah, it sounds like at this point in time, the glasses aren't really validated. But I like that she gave us some, you know, alternatives that were free also.

ZACH:

Yeah, absolutely. And also, the sunglasses factor. I love wearing sunglasses. I feel so justified and vindicated.

KATIE:

I'm awful about wearing sunglasses, and this was a really good reminder to me of, like, why it's important. I love that you asked her about what to look at when you're buying sunglasses because, I like as you mentioned, will just wear those, like, free pairs or, like, I don't know. Just somebody has, like, got too many sunglasses so they're just like,"Here, you can have those." And, you know, a friend or something at a bar gives you one. Like, "Just have them. I've got too many pairs." And, like, I don't know anything about these sunglasses. Like, are they really helping me? So, I was inspired by that. ZACH: Absolutely. And you can wear them inside. KATIE: Yeah. I'm probably not gonna do that, but --

ZACH:

Okay. Fair enough. I should be wearing some right now actually.

KATIE: You have light eyes. ZACH:

I do.

KATIE:

Yeah. So, Zach, you have a pair of blue light glasses. We've learned that they maybe don't work but don't hurt. Are you gonna keep wearing them?

ZACH:

No, like I told Dr. Malik, I think the next time, it's time for me to, you know, get new lenses. I will definitely say "no thank you" for the blue light lenses.

KATIE:

Okay. ZACH: Alright. Well, that's gonna do it for this episode of On Health with Houston Methodist. Be sure to share, like, and subscribe wherever you get your podcasts. We drop episodes Tuesday mornings. So, until next time, stay tuned and stay healthy.♪ ♪