Hey there and welcome to Paging Dr. Gupta. Thank you so much for joining us. As you know by now, this is the place where I get to answer your health questions, hear your concerns, and figure out what's on your mind. Jennifer is with us today. Who do we have first?

Hi Sanjay. Today's question actually comes from a few folks on our podcast team. We have questions about mouth taping, the trend where you literally tape your mouth shut while you sleep. People are saying it can help you breathe better and even sleep better, and we're seeing a lot of this online. But is it actually safe to try out and does it really work?

Alright, Jennifer, great question, and I gotta tell you, I'm not surprised this question is popping up on your feed. Quick anecdote. I walked into my oldest daughter's bedroom when she was visiting over the holidays, and guess what? I saw tape all over her mouth. Mouth taping is definitely having a moment, but I'm gonna tell you what you need to know about it, whether it's worth trying, and what to look out for right after the break.

'Okay, first things first. For those who haven't come across this trend, mouth taping. What exactly is it? You're probably imagining someone with tape over their mouth, hostage style, like in a movie, and guess what? You're actually not that far off. That's what surprised me so much when I walked in and saw Sage with that tape on her mouth. Mouth taping is the practice of taping your lips together overnight while you sleep. Now, mouth tape itself, that can come in a variety of formats. Some are skin-safe silicon, some are bandage style strips, all of them are much gentler than what you might be imagining in your home office, and they're definitely not the duct tape. But the bigger question, obviously, why do it?

Advocates say mouth taping can improve the quality of your sleep, can help you sleep longer, can help you stop snoring. People online have reported that it helps them wake up feeling more energized, less anxious. Some say there are even beauty benefits as well, claiming that it can improve the appearance of your face, your nose, and your jaw. Now, the logic here, as you probably have guessed by now, is that you're going to avoid sleeping with your mouth open.

But why exactly is it bad to sleep with your mouth open or to breathe through your mouth overnight? Well, we do know that mouth breathing has been linked to a lot of unpleasant things. Waking up feeling tired, snoring, dry mouth, which has been found to contribute to bad breath, cavities, a hoarse voice, dry lips, gum disease, and even something known as malocclusion. That's a condition where the upper and lower teeth don't align. Yeah, all that can happen from sleeping regularly with your mouth open. So the goal of mouth taping then is to have you breathe through your nose while you sleep, and that has proven benefits. Experts say that breathing through your nose is healthier. You know, there's these fine hairs in your nose. They're called cilia, and they actually have a job. They filter out dust and allergens and germs and environmental debris. Nose breathing also moisturizes incoming air, while dry air is breathed in through the mouth, and that can be irritating through the lungs. One doctor even told us that nasal breathing could be associated with lower blood pressure. How? Because it increases nitric oxide, a compound in your body that can be helpful for keeping your blood pressure under control. Lastly, you know, if you've ever meditated, you've often been asked to breathe in through your nose, because that is so relaxing. So it is used in yoga and meditation regularly. But the third question, and I think perhaps the most fundamental question then, is does mouth taping really mean you're gonna get those benefits?

And here's where it gets a little tricky. Sorry, Sage, but the answer is not necessarily. First of all, there's just not a lot of studies on this, and the studies that have been done have been limited and inconclusive. But secondly, some experts we talked to said mouth taping is probably pretty useless unless you're utilizing proper breathing technique. Now what does that mean? Well, think about this, and you can just do this along with me as you're listening to the podcast. In order for any of this to work, you have to make sure your tongue is placed properly in your mouth. And that means your tongue is in the up and forward position. Try this right now. So place the tip of your tongue directly behind your teeth, your front teeth, and then relax the tongue along the upper palate of your mouth and keep it there. So feel your tongue just behind your teeth. You shouldn't be able to talk, you shouldn't be able to say the word the, for example. Now, with your tongue sitting right behind your front teeth, try and breathe in through your mouth. You can't do it. You have to breathe in through your nose. And that is probably a great way to actually nose breathe instead of mouth breathe. Proper placement of the tongue in your mouth.

So it's not just as simple as taping your mouth closed. You've got to get the proper position of your mouth in the first place. And before you even go and try that, I do want to stress that mouth taping, perhaps no surprise, can be risky and even dangerous, especially in people who have sleep apnea, which is far more common than you might think. Roughly 30 million Americans are estimated to have it, and a huge chunk of that, about 23 million, are undiagnosed. So, point being you may have sleep apnea and not know it. If you do have sleep apnea, mouth taping could seriously restrict your airflow, therefore depriving your brain and your body of oxygen, which of course could be hugely problematic. We need to breathe. And even if you don't have sleep apnea, mouth taping can still really be dangerous. A recent analysis found taping or sealing the mouth closed, or even strapping the chin to keep the mouth closed could pose a serious risk of asphyxiation in the presence of nasal obstruction. So there's lots of reasons we have trouble breathing through our noses. Deviated septum, nasal polyps, sometimes nasal tumors, those are things. You should get addressed. So before you go out and start taping your mouth, there are some other things you should try first.

Look, it's great to hear about the trends we're seeing online, which could improve your sleep or health. I don't dismiss all of them outright. But first and foremost, you need to be educated about what really works, what doesn't work, and what might be dangerous. So keep that all in mind, and thanks to all of you who wrote in asking such a great question and staying curious about these trends.

Okay, we're gonna take a quick break, but after we come back, we got a great listener question about bone loss and calcium supplements.

Alright, we're back with paging Dr. Gupta. Jennifer is with us. What's the next question?

Our next question comes from a listener named Deb. Here's what she had to say.

Can you revisit the osteopenia issue and what is being recommended now as far as calcium supplements or not calcium supplements. And I have a neighbor, her doctor is giving her testosterone and said that it will help strengthen her bones, which doesn't sound right to me, I don't know. And I do have osteopenia and I'm seventy two years old, but I still am very active. I have two horses and I ride every day and I have a farm that I take care of myself. Thank you.

Okay, Deb, first of all, I gotta say I love hearing that you're still riding your horses. I have an equestrian in my family, and she's only 16 right now, but I imagine this being a lifelong sport. You're also taking care of your farm, you're staying active, that is awesome. So let's get right into it. First of all, a lot of people have probably heard of osteoporosis, but what is osteopenia? Well, it has to do with your bones and bone loss. And actually, osteopenia is a term that many doctors don't use as much anymore. The preferred term is low bone density. So that's what osteopenia is. It is a form of low bone density.

We talked to Dr. Deborah Sellmeyer, a director of the Metabolic Bone Diseases Program and Clinical Professor of Medicine at Stanford University School of Medicine, and she said that put simply, osteopenia is low bone density that is not at the somewhat arbitrary cut point that defines osteoporosis. So it's not as bad necessarily as osteoporosis. So thinner, weaker bones, yes, but not weak enough to be considered osteoporosis, somewhere in between. Okay, I wanted to make sure you got that definition.

'Now, to determine if you have low bone density, you would have to take a test. And that test is called a dual-energy x-ray absorbitometry, otherwise known as DEXA. That measures the mineral content of your bone. This does not hurt, it is not invasive. If you're concerned about bone loss, you should talk to your doctor about getting that test done. That way you're dealing with real information. Now, why should we care about this at all? The real concern here is fracture risk. How likely are your bones to break? And there are a few factors that determine fracture risk. It is a combination of a person's bone density, yes, but also other factors such as your age, if you've had a prior fracture, if you drink or smoke, or if you have conditions that might increase your risk, like rheumatoid arthritis. Fracture risk can be calculated using the FRAX online fracture risk calculator. That's F R A X if you want to look it up online.

'Now, keep in mind these are just numbers and no two people are alike. Some people with low bone density will be at higher fracture risk and may need medications. Others will be at lower risk and they're going to need nutrition and lifestyle measures only. So again, have a conversation with your doctor about your personal risk level and determine how you can best improve your bone density. Now, Deb, let's get to your specific question around calcium supplements. Calcium is important for bone health throughout your life. It helps build and preserve strong bones, and also helps support essential functions of the heart, muscles, and nerves. For all people, including those with low bone density, calcium intake should meet the recommended daily allowance -- which is a thousand milligrams a day for adults ages 19 to age 50, 1200 milligrams a day for women over the age of 50 and men over the age of 70. So for you, Deb, that would be 1200 milligrams a day.

'I should tell you there are great calcium calculators online. You can figure out how much calcium you're likely taking in through your diet. And I think a lot of people are surprised at how little calcium they get, especially if they're not regularly taking dairy products such as milk. A diet with no calcium-rich foods will give you about 250 to 300 milligrams of calcium a day only, okay? So you'll need to identify enough calcium-rich foods and/or supplements in addition to that to get the recommended intake per day. And just so you know, the good news is the absorption of calcium is the same from food, from fortified foods, and from supplements. So you can effectively use any combination of sources. Foods naturally high in calcium, again, no surprise, milk, yogurt, cheese. But there's also other non-dairy foods like canned fish with bones, like sardines or salmon, dark green leafy veggies like kale or broccoli. They're also great sources of calcium. And some milk substitutes or tofu, juices, cereals, they are fortified with calcium.

Now, quick caveat: don't go overboard. There is no benefit to megadosing with calcium. You just want to get the amount that you need. Dr. Sellmeyer says a calcium intake over 1500 milligrams a day can actually lead to high urine calcium and increase the risk of kidney stones. Also, for your friend who is taking testosterone, Dr. Sellmeyer told us there are no data on testosterone as a therapy for low bone density in women. In men with low testosterone, testosterone therapy can increase bone density by a small percentage, but it may not reduce fracture risk, that FRAX score that we were talking about earlier. In fact, some research has shown that testosterone treatment in men may be linked with the higher risk of fracture. So look, don't overdo it. Don't take things that are unnecessary, but certainly think about bone density, especially as you get older.

'Deb, I'm really happy you asked. When it comes to bone loss and calcium supplements, there is a lot of information out there. There is a lot to unpack. I really hope this helps you. That's a wrap for today's episode. Thanks again to all of you for sending in your health questions. No question is too big or too small. Keep them coming. You might just answer it on our next show. Reach out to us, record a voice memo, email it to AskSanjay at CNN.com, or give us a call, 470-396-0832, and leave a message. Thanks so much for listening.