Is there anything more soothing than a hot cup of cocoa or a mug of chai on a chilly winter day? While people across the globe have their own twists on cozy warm beverages, the idea of waking up and sipping on a hot cup of water, or doing the same before bed, is taking off on social media. While influencers tout the benefits of this practice based in Traditional Chinese Medicine, like improved digestion, a sped-up metabolism, and reduced period cramping, the truth is slightly less exciting.
“Drinking hot or warm water can feel good—and that matters—but its benefits are often overstated,” Diane Lindsay-Adler, registered dietician and assistant professor of pediatrics at New York Medical College, tells Popular Science.
Tea and soup really can help if you’re sick
Let’s start with the good stuff. If you have a cold or a sore throat, a cup of warm liquid can help temporarily soothe throat irritation, says Lindsay-Adler. To amp up those soothing effects, Arizona-based family physician Natasha Bhuyan suggests combining your warm water with garlic, honey, and lemon.
On a similar note, drinking hot water or hot soup can help break up nasal congestion, both Bhuyan and Lindsay-Adler add. One seminal 1978 study demonstrated that sipping warm soup or hot water can help clear out nasal mucus more quickly than drinking cold water or drinking a hot beverage via straw.
But, it’s crucial to point out that soothing is not the same as curing—warm beverages won’t magically fight the causes of a sore throat and a drippy nose, which come in the form of viruses and bacteria.
If you’re sick, a million pots of tea or hot water won’t help. If you’re running a fever of higher than 101.3 degrees Fahrenheit for more than three days, the Mayo Clinic suggests that it’s time to call the doctor.
Hot beverages may help your digestion
Another touted benefit of drinking hot beverages is the potential impact on the gastrointestinal tract. When something enters the stomach, nerves send a heads-up to the rest of your gastrointestinal system that something is coming, says Allison Miner, assistant professor of nutrition and food studies at George Mason University. When some people fill their stomach with warm liquid, this can cause the GI tract to move and trigger the reflex to eliminate, she adds.
“This is why warm beverages are commonly recommended by gastroenterologists as the first drink in the morning, when you’re sick or constipated,” adds Lindsay-Adler. “The effect is neurological and muscular: Warmth promotes relaxation and increases comfort, which may indirectly support digestion.”
But it doesn’t work for everyone, Miner warns. Kind of like with any sickness, getting to the root of the problem with a medical professional will do more than downing a multitude of hot beverages.
No, hot water doesn’t speed up your metabolism or detox the body
The idea of hot water speeding up your metabolism is, however, more myth than reality. “If something cold or hot enters our body and it’s not the temperature of our body, we will immediately adjust the temperature of that substance within milliseconds,” says Miner. “There is a metabolic cost when things are not at the temperature of our body, very slight metabolic cost…but it does not change our body weight.”
The same goes for the idea that hot water detoxes the body. No matter what temperature you take your beverages, detoxing comes down to the liver and kidneys, says Lindsay-Adler. The evidence that a hot glass of water is different from room-temperature or cold water simply isn’t there. Staying hydrated is what’s key for kidney and liver health, not counting degrees.
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Very hot drinks can pose real problems
In terms of risks of hot drinks, there’s only really one—drinking a beverage that is too hot. Drinking beverages above 149 degrees Fahrenheit every day may irritate your esophagus, even upping the risk of esophageal cancer, says Bhuyan.
You don’t have to ditch your beverage habits entirely, but maybe limit those extra-hot beverages to a once-daily treat.
Why hydration—in any form—is the real key
The most important thing we can do for our health, in terms of hydration, is drink more water at whatever temperature it is that you like best.
“If you’re thinking about hydration, beverage temperature is far down the list of priorities,” says Lindsay-Adler. “Total fluid intake matters far more than whether your water is hot or cold. Many adults—especially older adults—are chronically underhydrated simply because they don’t drink enough.”
A commonly cited number for the amount of water people should be drinking is in the range of four to six cups, but it varies from individual to individual. You don’t have to drink all day long, adds Miner, since a well-balanced diet can be full of hydration—think tomatoes, cucumbers, melons, oranges, soups, and more.
If you’re feeling dehydrated, which can come in the form of headaches, dizziness, and constipation, take a look at your diet. A diet full of too much sodium or protein can cause you to be dehydrated, says Miner, because your body spends a lot of water urinating out the stuff your body doesn’t need. Additionally, too few carbohydrates means that your body may be unable to hold onto the water you do consume.
Moral of the story: if drinking hot water makes you drink more water, then fire up the kettle. But if hot beverages aren’t your thing, you’ll still see plenty of benefits by just carrying around a room temperature water bottle.
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