Miso soup is a solid choice when you’re feeling nauseous. It’s warm, broth-based, light on the stomach, and delivers sodium and fluids your body needs, especially if nausea has kept you from eating or drinking normally. Dietitians at Dana-Farber Cancer Institute specifically recommend tofu miso soup as an easy option for patients dealing with nausea and poor appetite during cancer treatment, alongside other broth-based soups like chicken noodle.
Why Miso Soup Settles an Upset Stomach
Several things about miso soup make it particularly gentle on a queasy stomach. First, it’s a warm liquid, which is easier for your digestive system to handle than solid food when you’re nauseous. Sipping small amounts of broth helps you stay hydrated without overwhelming your stomach the way a full meal would.
Second, the soy protein in miso has been broken down through fermentation. During that process, bacteria use enzymes to chop large soy proteins into much smaller fragments. A study in Scientific Reports found that fermentation eliminated most of the larger protein molecules in soybeans while also reducing compounds called protease inhibitors that normally make soy harder to digest. The result is a protein source your stomach doesn’t have to work as hard to process, which matters when digestion already feels fragile.
Third, miso soup naturally contains sodium and small amounts of protein. A standard bowl (about 9 ounces) provides roughly 450 mg of sodium and around 5.5 grams of protein. If you’ve been vomiting or unable to eat, that sodium helps replace lost electrolytes, while the protein gives your body something to work with without being heavy.
How It Compares to Chicken Noodle Soup
Chicken noodle soup and miso soup both appear on lists of recommended foods for gastroenteritis recovery, and for good reason. Both are broth-based, hydrating, and provide electrolytes. A cup of standard canned chicken noodle soup has about 691 mg of sodium, noticeably more than a bowl of miso soup. If you’re watching your salt intake, miso soup is the lighter option. It also tends to feel less “heavy” since it doesn’t contain noodles or chunks of meat, which can be a plus when even the thought of solid food triggers nausea.
That said, the best soup for nausea is whichever one you can actually get down. If miso’s flavor doesn’t appeal to you when you’re sick, chicken broth or plain vegetable soup will do much of the same work.
White Miso vs. Red Miso for Nausea
If you’re making miso soup specifically to calm nausea, white (shiro) miso is the better pick. It has a shorter fermentation time and a mild, slightly sweet flavor with a delicate finish. Red miso, by contrast, is bold, earthy, and intensely savory. That robustness can be appealing when you’re feeling well, but strong flavors tend to be the last thing you want when your stomach is turning. White miso is gentle enough that it won’t overwhelm your senses.
The Probiotic Question
Miso paste contains beneficial live bacteria from fermentation, and you may have heard these probiotics help with digestive issues. There’s a catch, though: the live bacteria in miso start dying at temperatures above about 115°F (46°C), and soup is typically served much hotter than that. If you boil your miso directly in the pot, you’re killing most of the probiotic content.
To preserve more of those bacteria, remove your soup from heat and let it cool slightly before stirring in the miso paste. A common technique is to mix the miso with a small amount of warm water in a separate bowl to create a smooth slurry, then add that to the pot once it’s off the burner and has dropped closer to 120°F to 158°F. Even with this approach, some bacteria won’t survive. But the fermentation process creates beneficial compounds beyond just live bacteria, including the pre-digested proteins and amino acids that make miso easy on your stomach regardless of temperature.
Sodium and Blood Pressure
People who watch their sodium sometimes worry about miso soup. Interestingly, research in rats bred to be salt-sensitive found that a miso diet containing 2.3% sodium chloride did not raise blood pressure, while the same concentration of plain sodium chloride did. The other compounds in miso appear to offset some of sodium’s effects on blood pressure, though this has been studied more thoroughly in animals than humans. Still, at roughly 450 mg of sodium per bowl, miso soup is a moderate-sodium food, not a high one, and drinking a bowl or two when you’re nauseous is unlikely to be a concern for most people.
When Miso Soup Could Make Nausea Worse
For most people, miso soup is a safe and soothing option. But if you have histamine intolerance, it could backfire. Miso is a fermented food, and fermented foods are among the most common triggers for histamine-related symptoms. In people who don’t break down histamine efficiently, consuming miso can actually cause nausea, along with hives, itchy eyes, and sneezing. This affects a relatively small number of people, but if you notice that fermented foods like aged cheese, sauerkraut, or wine consistently make you feel worse, miso may not be your best bet. A plain, non-fermented broth would be a safer alternative.
How to Make It When You’re Feeling Sick
Keep it simple. You don’t need a complex recipe when your goal is just to settle your stomach. Heat water or a light vegetable broth until it simmers, then turn off the heat. Let it cool for a minute or two, then stir in one to two tablespoons of white miso paste until dissolved. That’s it. If you want a bit more substance and your stomach can handle it, add small cubes of soft tofu or a few slices of green onion.
Sip it slowly rather than drinking the whole bowl at once. Small, frequent sips give your stomach time to adjust and reduce the chance of triggering more nausea. If the first few sips stay down comfortably, you can gradually drink more.