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Hot sleeper? Here are the 9 best comforters for a sweat-free slumber

Hot sleeper? Here are the 9 best comforters for a sweat-free slumber

CNN27-06-2025
Comforters for hot sleepers quick picks
NASA-engineered cooling technology: Slumber Cloud UltraCool Comforter
Our favorite down comforter: Brooklinen Down Comforter
An affordable down-alternative option: Bedsure Premium Down-Alternative Comforter We wait all winter to bask in the warmer days of summer, but the one place many of us want to keep cool and comfortable year-round is the bedroom. And it makes sense because your core body temperature naturally drops while you sleep to help give you a restful night. If your sleep environment is too warm, it can interfere with your body's ability to cool down properly, according to Dr. Andrea Matsumura, board-certified sleep specialist and spokesperson for the American Academy of Sleep Medicine. 'This disruption in thermoregulation can throw off your circadian rhythm — your internal clock — leading to fragmented or poor-quality sleep,' she said.
Finding the right balance between cozy compression and cooling in your bedding can be frustrating. To prevent you from stripping every blanket off your bed in a sweaty rage, we consulted a sleep expert, two textile experts and our on-staff editors to round up a list of the best comforters for hot sleepers.
Slumber Cloud UltraCool Comforter
After a lifetime of buying whatever kind of bedding was on sale, I finally upgraded to this Slumber Cloud comforter a few years ago. I'm a hot sleeper by nature, and at the time, my stuffy NYC apartment was unbelievably warm year-round (thanks to the heat from the bakery directly below). With its NASA-engineered fiberfill that regulates your body temperature and a cooling nylon and spandex cover that feels silky against the skin, this comforter was a lifesaver both then and now. I love that it has some weight to give you a compressed and bundled-up feeling, but it remains cool, even when I pop a linen duvet cover over it for more style. I'm not the only one who loves it either; CNN Underscored deals editor Jacqueline Saguin is a fan too.
Rest Evercool Cooling Comforter
Made of a proprietary Evercool cooling fabric, this comforter promises to stay cool to the touch all night long and even claims to outperform other breathable bedding materials like cotton, bamboo and silk. Soft to the touch and lightweight, the comforter is made from a blend of cooling nylon and spandex. The fibers of the fabric are densely knitted together to drape over your body without trapping heat. It's also machine-washable and dryer-safe, which Matsumura said are features that can help keep your bedding more hygienic since hot sleepers tend to sweat more.
Brooklinen Down Comforter
This Brooklinen comforter is our favorite down comforter. CNN Underscored associate testing writer Joe Bloss compared the comforter, which has a 100% cotton sateen shell, to snoozing among the clouds. With 700-fill power, it's heavier than some other down comforters we've tried, but Bloss never felt overheated or sweaty while using it. Plus, it's available in three weight options — lightweight, all-season and ultra-warm — so you can choose the best fit for your preferences.Read our review
Cozy Earth Bamboo Viscose Comforter
If you're looking for an alternative to cotton comforters, Matsumura said bamboo also makes a great choice since it's breathable and won't trap heat like other synthetic fibers. This Cozy Earth comforter is a bit of a splurge, but it's made from 100% viscose from bamboo, which also has natural moisture-wicking properties to ensure you get out of bed feeling fresh.
Puredown Pro Ultra-Lightweight Cooling Down Comforter
Filled with a mix of white duck down and white duck feathers, this Puredown comforter has two mesh strips designed to enhance air circulation and ensure heat quickly dissipates when temperatures begin to rise. You can use this lightweight comforter by itself in the summer and layer it with extra quilts or blankets in the winter for added warmth.
Buffy Cloud Comforter
CNN Underscored testing and updates writer Michelle Rae Uy said the Buffy Cloud Comforter is the perfect all-season option for keeping cozy during Los Angeles winters and cool during the summer. This Buffy comforter is made with lyocell fibers. 'Lyocell, a material made from sustainably sourced wood pulp, is ultra-soft and is great at pulling moisture away from your body, which helps regulate your temperature through the night,' Inga Bleyer, head of marketing and communication at Oeko-Tex, said. And if all this cooling comfort wasn't enough, this machine-washable pick comes in 10 colors and earned a top spot in our comforters guide for its soft feel and sturdy construction.Read our review
Silk & Snow Down-Alternative Comforter
'Down and down-alternative fills vary in loft and warmth,' Bleyer said. 'If you're a hot sleeper, look for a comforter labeled as 'lightweight' or 'summer weight.' These typically have less fill, which means they trap less heat.' This Silk & Snow comforter is made with a microfiber fill that comes in lightweight as well as all-season and winter-weight options. Designed to feel just like real down, this comforter also has a 100% cotton shell, is hypoallergenic and is machine-washable so everyone can comfortably enjoy its coziness.
Bedsure Premium Down-Alternative Comforter
Comforter costs can quickly climb into the range of a few hundred dollars. If you're just looking for something to get you through the sticky summer months without costing a fortune, try this Bedsure comforter. With a double-brushed shell for a soft and smooth feel on the skin, this down-alternative comforter is also Oeko-Tex Standard 100 certified and free from substances that can be harmful to human health. In addition to classic white, you can also grab this comforter in six other colors, including black, purple, green and navy.
Sijo AiryWeight Cooling Eucalyptus Comforter
Made of eucalyptus fibers for cool, sweat-free sleep, this Sijo comforter is also gently weighted, so you can have calming compression to unwind at night without feeling stuffy. The eucalyptus fibers help absorb moisture quickly, making this comforter a great option for those who deal with sticky and humid summer nights. Due to overheating and sweating, hot sleepers can be more likely to stir awake during the night or find it difficult to fall asleep. For optimal health and well-being, the American Academy of Sleep Medicine recommends that your sleep environment be dark, cool and quiet — almost like a cave. Though what's comfortable for you will depend on your personal preference, Matsumura said you should generally keep your bedroom at a temperature of around 68 degrees Fahrenheit. If you still don't feel comfortable, you can try adding in a cooling fan or some blackout curtains to help cool off the space even more.
Material and fill
'If you're a hot sleeper, choosing the right bedding can make all the difference,' Matsumura said. 'The best cooling materials share a few key traits: They're breathable, moisture-wicking and promote airflow.'
Natural fibers like cotton, linen, silk and lyocell are some of the best options for hot sleepers, according to Bleyer, since they're breathable, moisture-wicking and allow for better airflow. Matsumura recommends hot sleepers stay away from heavy, non-breathable materials like flannel or fleece, as well as synthetic-only fabrics that tend to trap heat during the night.
The fill of your comforter also plays a role in keeping you cool, since it dictates how well air can circulate through the material. Bleyer recommends looking for comforters labeled as 'lightweight' or 'summer weight' as these tend to be packed with less fill. Matsumura added that it can also be a good idea to look for moisture-wicking fabrics that can draw sweat away from the body as you sleep.
Care
Care is also essential for ensuring that your bedding lasts longer than one season. Bleyer recommends avoiding washing comforters with fabric softeners as they can coat the fibers and reduce breathability. Fabrics like lyocell and silk can be washed on a gentle cycle with cold water and mild detergent. Bleyer said materials like linen and cotton can handle regular cycles, but still prefer cooler water settings and low heat when drying to help preserve their natural structure.
When the summer ends, you'll want to make sure your seasonal bedding is well stored for the off-season too. 'When storing, keep bedding in a breathable cotton bag rather than plastic to prevent trapping moisture that can cause mildew or fabric breakdown,' Bleyer said. 'As for durability, linen and cotton tend to get better with age if cared for properly; think softer, cozier and still breathable.'
The following FAQs have been answered by sleep expert Dr. Andrea Matsumura and textile experts Inga Bleyer and Preeti Arya.
What is the best material for bedding for hot sleepers?
What is the best material for bedding for hot sleepers?
For hot sleepers, Matsumura recommends looking for bedding made with breathable, natural materials like cotton, bamboo or linen, and avoiding heavier fabrics like fleece and flannel or synthetic-only fabrics that trap heat.
Bleyer also recommends natural fabrics, noting that cotton, especially with a percale weave, is light and crisp for sleeping. 'Linen is a bit more textured, but it's great for hot sleepers because it's super breathable and has natural thermoregulating properties,' Bleyer said.
Are quilts, blankets or comforters best for hot sleepers?
Are quilts, blankets or comforters best for hot sleepers?
Ultimately, your choice of bedding boils down to personal preference. Hot sleepers can find success using comforters, so long as they're made of breathable materials and allow for good airflow. But Matsumura said that if a hot sleeper still feels too warm under a comforter, they can opt to use lightweight sheets or blankets that are easier to remove from the body and can better help them stay cool.
Our experts agreed that natural fibers are better at keeping you cool than synthetic ones, but Preeti Arya, an assistant professor of textile development and marketing at the Fashion Institute of Technology, said that no matter what kind of fiber is used to fill a comforter or duvet, a fluffy spread will still trap some amount of heat. For those looking to be ultra-cool, Arya recommends using 'flat throws, thick sheets or duvets without any stuffing or filling.'
Are down comforters good for hot sleepers?
Are down comforters good for hot sleepers?
Yes, hot sleepers can use down comforters. Matsumura recommends shopping for a down or down-alternative fill that is lightweight. She also recommends looking for comforters made with moisture-wicking fabrics or that have specific cooling properties to better aid hot sleepers.
Since hot sleepers tend to be more prone to sweating during the night, Matsumura also said it's a good idea to look for comforters that are machine-washable, both to keep your sleep setup more hygienic and make regular cleaning easier.
What else can I do if I still feel hot at night?
What else can I do if I still feel hot at night?
If you're still struggling to cool down at night, Matsumura has some other tips that might help you rest better. Make sure to drink plenty of water throughout the day to stay hydrated and avoid heavy exercise too close to bedtime, as exercise can raise body temperature.
If you wake up hot during the night, try changing clothes, swapping your comforter for a lighter layer or lowering the room temperature. You might also try taking a lukewarm shower before bedtime. 'A tepid shower can help dilate blood vessels to the skin; heat then is lost through the skin in the minutes after you exit the shower, allowing body temperature to drop,' Matsumura said.
After trying these at-home fixes, if you still find yourself sweating in the middle of the night, Matsumura said you should consult a sleep doctor, as these could be signs of a sleep disorder, such as sleep apnea.
For this article, we consulted the following sleep and textile experts to gain their professional insights.
Dr. Andrea Matsumura, board-certified sleep specialist and spokesperson for the American Academy of Sleep Medicine
Inga Bleyer, head of marketing and communication at Oeko-Tex
Preeti Arya, assistant professor of textile development and marketing at the Fashion Institute of Technology
CNN Underscored has a team of writers and editors who have many years of experience testing, researching and recommending products, and they ensure each article is carefully edited and products are properly vetted. We talk to top experts when relevant to make certain we are testing each product accurately, recommending only the best products and considering the pros and cons of each item. For this story, associate editor Jillian Tracy consulted a sleep specialist and two textile experts to better understand what comforters and materials can help hot sleepers stay cool.
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Early findings in other hibernators indicate that instead of producing urine when hibernating, animals recycle the nitrogen in urea, and microbes in their guts could be ingesting and metabolizing it into amino acids, which make new muscles. If Fedorov and Goropashnaya can identify a single, extra-powerful 'upstream' gene responsible for switching on this muscle regeneration, it could have profound medical implications. The muscles of bedbound ICU patients wouldn't melt away within weeks, and astronauts could build muscles while resting. But what if all the disparate and remarkable processes of hibernation could be globally activated all at once—with a drug? To find out, scientists are looking deeper into the animal kingdom to unlock the secrets of the most extreme hibernator of all. (It's not just bears: These hibernating animals may surprise you.) The arctic ground squirrel, a diminutive rodent with gold-tinted fur, a button nose, and a tiny pair of Bugs Bunny-like front incisors, can drastically drop its body temperature and heart rate, slow to one breath per minute, and survive months in subzero conditions. The squirrels are also, for the most part, far easier to study than bears. An arctic ground squirrel remains in hibernation in a lab at the Institute of Arctic Biology at the University of Alaska Fairbanks. 'Until they open their eyes,' says Kelly Drew, the affable, silver-haired neuroscientist who directs the Center for Transformative Research in Metabolism at the IAB, after digging through a nest of cotton and wood shavings to pull out a frozen, furry snowball. 'Then they can bite.' In the early 2000s, Drew persuaded the U.S. military to fund a search for the brain chemicals that trigger hibernation in the squirrels. If she could identify those chemicals, she suggested, she could then test them on humans, in hopes of developing new ways to cool wounded soldiers on the battlefield. Drew's first breakthrough with the squirrels arrived in 2005 when an undergraduate research assistant chanced upon a paper from a Japanese lab while combing through scientific literature. The Japanese group had actually achieved the opposite of what Drew hoped to do. They'd found a drug that woke hibernating hamsters by blocking their brain cells' response to a specific chemical called adenosine. Drew assigned a graduate student to inject a synthetic version of adenosine, a drug called 6-Cyclohexyladenosine, or CHA, directly into the brains of her squirrels. Rather than blocking adenosine, which is how the caffeine in your coffee works its magic, CHA replicates its effects. When the graduate student dosed a squirrel's brain in the summer, outside of hibernation season, nothing happened. But when he repeated it closer to hibernation season, the CHA put the animal into such a deep state of torpor, the student initially thought he had killed it. 'He was super sad because that's a big deal,' Drew recalls. 'He takes the animal out for the vet to do the necropsy. The vet gets the tools out, he's going to start cutting open this dead animal, and it starts to move.' Her lab had done it. They'd found a way to put a squirrel in hibernation mode, like flipping a switch. Temporarily removed from its refrigerated hibernation den and settled on a bed of wood shavings, this arctic ground squirrel remained in a state of torpor for over an hour before beginning to stir. The squirrels survive their long hibernation by warming up for short periods every few weeks. On the opposite side of the world, at the University of Bologna in Italy, around the same time Drew's grad student stumbled on that Japanese paper about adenosine, another grad student named Domenico Tupone was charting a similar path. The focus of his laboratory research wasn't hibernation per se but a component of it: identifying the brain circuits that regulate body temperature during sleep. His team suspected that a small patch of neurons at the base of an ordinary rat's brain helped convey temperature-control signals to the periphery of the body. They temporarily immobilized those neurons with an injection, then placed the rat in a cold, dark cage. The experiment validated their hypothesis. As Tupone and his colleagues watched, the rat sank into a state of hypothermia so extreme it should have proved fatal. That's when things got weird. Six hours and four injections later, the hypothermic rat was still alive. And when the team finally removed it from its cage and warmed it up, the rat behaved, at least outwardly, as if nothing had happened. Afterward, as Tupone and his colleagues examined the brain waves picked up by a web of electrodes attached to the rodent's skull, scientist Matteo Cerri made an observation that altered the course of Tupone's future research. The peaks and valleys of the brain waves looked familiar. Cerri had seen the same patterns in hibernating animals. But there was one crucial difference. Unlike arctic ground squirrels, rats do not naturally hibernate. Tupone had to know: If a non-hibernating animal could be safely induced into hibernation, then maybe humans could do it too? In the years that followed, Tupone obsessed over scraps of paper in dimly lit bars, sketching out what a brain circuit capable of triggering hibernation in humans might look like. In bed, he tossed and turned, fantasizing about a 'revolutionary' IV-administered drug akin to Drew's 'hibernation mimetic' that paramedics could use to slow cell death on the way to the hospital. He became convinced that if it could be accomplished safely, inducing natural torpor in humans would upend basic science. The next step for both researchers, though—human trials—presented their stiffest obstacle yet. In order to administer Drew's 'hibernation mimetic' to ground squirrels, her team often had to perform invasive brain surgeries. For humans, the drug would need to be delivered via IV. The trouble is, adenosine receptors are present throughout the body, and activating them globally can trigger unwanted side effects, including cardiac arrest. After four more years of frustrating trial and error, Drew paired the drug with a compound that fixed the heart attack problem, and she's currently trying to solve the additional obstacle of fluctuating blood glucose levels, which in extreme cases can cause seizures in lab animals and even death. 'It works; it definitely cools them,' Drew says. 'We're just trying to tweak it so it's as safe as possible.' Clinicians have lots of devices to regulate temperature, 'but the human body typically fights it. By avoiding that cold defense response, which is what our hibernation mimetic does, then the clinician has the ability to dial in whatever temperature they want.' In minutes, not hours. Tupone, meanwhile, was working on parallel tracks at Portland's Oregon Health & Science University under Shaun Morrison, one of the world's experts on the brain circuits that control body temperature. Tupone's primary focus was on extending the map of temperature--related circuits into new parts of the brain, but in his spare time, he continued to hunt for the elusive hibernation switch. Around 2016, he stumbled upon a curious biological phenomenon that convinced him he was getting close. He and Morrison were attempting to confirm their map of the brain's thermoregulatory control system, in an experiment similar to the one in which the unexpected survival of those hypothermic Italian rats had blown his mind. This time, Tupone used a small knife to sever the bundle of nerves running to the rat's brain stem, cutting off the pathway that relays temperature--control signals down to the body's periphery. Once again, though, Tupone's results seemed to flip the expected rule of mammalian physiology. Rather than disabling the ability of the rat to respond to heat or cold, Tupone's incision somehow enhanced it. When Tupone wrapped the rat in a plastic blanket and ran hot water over it, its body began generating even more heat. When he used freezing cold water, the rat's brain seemed to allow its body temperature to fall even faster. An arctic ground squirrel emerges from a burrow in the foothills of Alaska's Brooks Range shortly after its eight-month hibernation. Each fall, Colorado State University scientists working at the nearby Toolik Field Station collar squirrels with devices to track body temperature data and light, which tells them if a squirrel is in or out of its burrow. In the spring, new squirrels are ear-tagged and weighed before their summer of foraging begins. The long-term study is revealing how climate change is affecting the biology of these important hibernators. Tupone and Morrison quickly concluded they had discovered something profound. The results suggested that a second, previously undiscovered brain circuit capable of modulating body temperature existed—one that facilitated the transition in and out of hibernation. They named the phenomenon 'thermoregulatory inversion' (TI). But where exactly was this circuit, and how could it be activated? After eight years of trial and error, Tupone and Morrison published a paper this past January announcing they'd found a small patch of neurons in the rat's hypothalamus—the ventromedial periventricular area (VMPeA)—that, when activated, not only seems to slow metabolism, lower body temperature, and induce brain waves and cardiac patterns unique to hibernation but also sets in motion phenomena that flip the body's normal temperature-control system on its head, facilitating the transition into and out of the torpor state. They'd found it: the elusive 'torpor switch.' Tupone believes the switch is connected to an incomplete version of the hibernation circuitry that still exists in many animals. To disable it, he hypothesizes, evolution did the most efficient thing. It simply removed the connection between the circuitry and the switch that would flip it on automatically. 'It is like you have all the cables inside your walls to turn on a light,' he says, but you've removed the connection to the switch that controls that light. 'We think humans have all the circuitry.' Our switch, he believes, just isn't connected anymore. To back up his findings, Tupone is now collaborating with Kelly Drew's lab to find the analogous circuitry—and the switch—in arctic ground squirrels. And he's laying the groundwork for a drug of his own that can flip the switch in his rats without invasive brain surgery. Each advance, though, generates more mysteries. To flip their switch on and off in the study they published in January, Tupone and Morrison had to use invasive brain surgery and manually apply a drug to the general area where it was located. Even that infinitesimally small patch of the brain still contained millions of neurons, including an entire neighborhood of unrelated neurons surrounding it. To find a drug specific enough to give to humans without immense side effects, Tupone will need to identify the precise neurons around the switch and design a drug that will target only those involved in hibernation. That's just the tip of the iceberg, though. To suppress the shivering response in humans, anesthesiologists typically administer muscle relaxants or paralyzing drugs, which suppress breathing, so doctors have to intubate patients … which requires putting them into a medically induced coma. This is why induced hypothermia is not available outside hospitals. It's also not currently an option for stroke patients, because of the dangerous drop in blood pressure that often occurs during the gap between administering anesthesia and intubating a patient, which can deprive the brain of even more oxygen at a moment when dangerous blockages are already suffocating its cells. Rats don't hibernate. But what if they could? Neurologist Domenico Tupone and fellow researchers from the University of Oregon say they've identified a 'torpor switch' in rat brain neurons (projected on the wall) that can be activated to send the rodents into a deep state of hibernation. Identifying this circuitry in non-hibernators could be a breakthrough in the human hibernation effort. 'It can actually worsen a stroke,' says researcher Cal-laway, from the University of Pittsburgh. 'But boy, it sure would be nice to lower your body temperature and let your brain tolerate the stroke longer until I can get you to the cath lab and take that blood clot out.' As an emergency physician, Callaway understands better than most the potential applications for humans, as well as the challenges presented by making the leap from bears and squirrels to humans. He's been researching and refining the techniques used to induce hypothermia in cardiac and brain-injured patients since the 1990s, and he's also a former chair of the American Heart Association's Emergency Cardiovascular Care Committee, which is why NASA awarded him a grant through the Translational Research Institute for Space Health to explore whether his techniques can be applied to the metabolic needs of astronauts. So far, there are problems. The drop in blood pressure and heart rate in his five healthy volunteers was so extreme that those with cardiovascular or other medical conditions might not be able to tolerate it. And within days, all five of the 'pretend astronauts' had developed a tolerance to his sedative, suggesting, among other things, that its effectiveness would fade over time. Those are solvable problems, Callaway says. 'This is just the first step' in a process that he believes will take 10 to 15 years—a mere nap for Rip Van Winkle. 'There's a lot of science to be done,' he says. But he's excited by the progress: 'I don't think it's pie-in-the-sky anymore.' To keep the pretend astronauts inspired during the human trial, Callaway's team had plastered the walls of their lab with posters: a satellite floating in space above the swirling blues and whites of Earth; the cratered, gleaming surface of a moonlike planet; the rainbow-hued burst of starlight, radiating from a distant galaxy. For now, such destinations are accessible only in our dreams. But someday in the not too distant future, a real astronaut might awaken from a hibernation-like slumber to gaze on the real thing.

HoneyNaps Launches Cloud Version of AI Sleep Diagnostic Software "SOMNUM™" at SLEEP 2025
HoneyNaps Launches Cloud Version of AI Sleep Diagnostic Software "SOMNUM™" at SLEEP 2025

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  • Yahoo

HoneyNaps Launches Cloud Version of AI Sleep Diagnostic Software "SOMNUM™" at SLEEP 2025

HIPAA-compliant cloud-based service provides diagnostic reports via the web with no installation required AI-powered trial service offered, highlighting potential for hospital-specific integration Presented performance of heart rate-based sleep stage estimation algorithm through oral and poster presentations BOSTON, Aug. 19, 2025 /PRNewswire/ -- HoneyNaps, a medical AI diagnostics company, showcased both its technological capabilities and research achievements at SLEEP 2025, the world's largest sleep medicine conference held in Seattle, USA, from June 8 to 11. SLEEP 2025 is a prestigious international conference co-hosted by the American Academy of Sleep Medicine (AASM) and the Sleep Research Society (SRS), drawing approximately 5,000 sleep professionals and featuring over 1,000 of the latest research presentations. HoneyNaps has been the only Korean company to participate in the conference for four consecutive years since 2022. At this year's conference, the company further reinforced its academic credibility through both oral and poster presentations. Notably, in an oral presentation titled "Development and Evaluation of an Exclusively ECG-based Deep Learning Model for Sleep Staging," the company introduced a deep learning model that reliably classifies sleep stages using single-lead ECG signals, demonstrating significantly improved accuracy over conventional methods. At its exhibition booth, HoneyNaps drew attention by unveiling SOMNUM™ Cloud, an AI solution for automated analysis of polysomnography (PSG) data. Users can upload EDF files extracted from PSG devices to the cloud, where the AI engine automatically analyzes the data and generates a comprehensive report — easily downloadable online with no software installation required. During the conference, HoneyNaps offered a free trial consisting of three AI analyses, enabling visitors to experience SOMNUM Cloud in a clinical-like setting. The hands-on program was met with enthusiastic feedback from U.S. sleep physicians and RPSGTs (Registered Polysomnographic Technologists). Taekyoung (Sean) Ha, PhD, President of HoneyNaps USA, stated, "With its cloud-based architecture, streamlined implementation process, and HIPAA compliance, more than 100 U.S. medical institutions expressed interest in potential adoption. We also held individual meetings with leading global sleep companies to discuss potential strategic collaborations". For further information, please contact:HoneyNaps USA, Kwon / Managing DirectorEmail: sleep@ #517, SPACES, 361 Newbury Street, Boston, MA, 02115Website: View original content to download multimedia: SOURCE HoneyNaps Error in retrieving data Sign in to access your portfolio Error in retrieving data Error in retrieving data Error in retrieving data Error in retrieving data

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