Rice water for diarrhea is made by boiling rice in extra water, then straining off and saving the starchy liquid. The method has been used across South and Southeast Asia for generations, and clinical research confirms that rice-based fluids can reduce stool output, particularly in cases of cholera-related diarrhea. Making it at home takes about 20 to 30 minutes and requires nothing more than rice, clean water, and a pinch of salt. The details of preparation matter, though, because the goal is not just hydration but delivering a slow-release source of glucose to your gut.
A Simple Recipe
You need one cup of plain white rice (any variety works, though short-grain rice releases more starch), six cups of clean water, and half a teaspoon of table salt. Rinse the rice briefly under running water to remove surface debris, but do not wash it so thoroughly that you strip all the starch. Place the rice and the six cups of water in a pot and bring it to a boil. Reduce the heat and let it simmer, uncovered, for 20 to 25 minutes. The water should turn cloudy and slightly thickened.
Strain the liquid through a fine mesh strainer or cheesecloth into a clean container. Stir in the salt while the water is still warm so it dissolves completely. Let it cool to a drinkable temperature before serving. The leftover cooked rice is perfectly fine to eat and can help firm up stools on its own, since it is part of the well-known BRAT diet approach for upset stomachs.
If you want to bring the rice water closer to a proper oral rehydration solution, you can also dissolve about two tablespoons of sugar or a tablespoon of honey (for adults and children over one year) into the strained liquid. The combination of salt and sugar activates the same intestinal transport pathway that commercial rehydration packets rely on: sodium and glucose are absorbed together across the gut lining, pulling water along with them. Without at least some salt, you are rehydrating but not replacing lost electrolytes.
Why Rice Water Works
Plain sugar-and-salt oral rehydration solutions replace fluids but do not slow down the diarrhea itself. Rice water has an advantage because its starch molecules break down gradually in the small intestine, releasing glucose slowly rather than flooding the gut all at once. That slow release pulls more water out of the intestinal lumen and into the bloodstream, effectively reducing the volume of each watery stool. A meta-analysis of 13 clinical trials found that rice-based solutions cut stool output by about 36% in adults with cholera and 32% in children with cholera during the first 24 hours, compared to standard glucose-based oral rehydration solutions.1PubMed Central. Impact of rice based oral rehydration solution on stool output and duration of diarrhoea: meta-analysis of 13 clinical trials
Animal research suggests another piece of the puzzle. Modified starch added to oral rehydration solutions reversed sodium secretion in the intestine and improved the absorption of water, potassium, and glucose, compared to standard solutions without the starch component.2Pediatric Research. Modified Starch Enhances Absorption and Accelerates Recovery in Experimental Diarrhea in Rats In plain terms, the starch does not just add calories. It actively changes the direction fluid moves across the intestinal wall, flipping the gut from “leaking fluid out” to “absorbing fluid in.”
The Cholera Distinction
This is where the evidence gets more complicated than the folk remedy suggests. The dramatic reductions in stool output that make headlines come almost entirely from studies of cholera, which causes a specific type of secretory diarrhea. A Cochrane review pooling data from multiple trials found that people with cholera given rice-based oral rehydration had stool volumes about 67 mL per kilogram lower in children and 51 mL per kilogram lower in adults over 24 hours, compared to those on standard glucose solutions. But in infants and children with non-cholera diarrhea, the reduction was only about 4 mL per kilogram, a difference so small it was not statistically meaningful.3PubMed. Rice-based oral rehydration solution for treating diarrhoea
That does not mean rice water is useless for ordinary stomach bugs. It still provides fluids, electrolytes (when salted), and easily absorbed calories at a time when you may not be able to keep much food down. The starch also contributes to the recovery diet. It simply means you should not expect rice water to dramatically shorten or reduce a typical bout of viral gastroenteritis the way it can for cholera. For most everyday diarrhea caused by norovirus, rotavirus, food poisoning, or traveler’s diarrhea, the main benefit of rice water is keeping you hydrated and nourished while the illness runs its course.
Is It Safe for Babies and Young Children?
One of the earliest clinical studies on rice water specifically enrolled 130 infants with gastroenteritis and found that none died and none experienced harmful side effects. The researchers concluded that rice water could serve as a practical alternative to commercial oral rehydration solutions, especially in settings where those packets are hard to find or keep sterile.4PubMed. Rice water in treatment of infantile gastroenteritis A later trial focused specifically on infants younger than six months found that rice-based oral rehydration solution was both safe and as effective as standard glucose-based solutions for treating acute diarrhea in that age group.5Journal of Pediatric Gastroenterology and Nutrition. Safety and Efficacy of a Rice‐Based Oral Rehydration Salt Solutions in the Treatment of Diarrhea in Infants Less Than 6 Months of Age
A few practical cautions apply when giving rice water to a young child. Do not use rice water as a replacement for breast milk or formula. It lacks the protein, fat, and micronutrients a baby needs. Offer it between or alongside regular feedings as a supplemental fluid. Keep the salt modest for infants, roughly a quarter teaspoon per liter, to avoid overloading immature kidneys. And never add honey for children under one year because of the botulism risk. If a baby is showing signs of moderate to severe dehydration, such as no tears when crying, a sunken soft spot on the head, or going more than six hours without a wet diaper, get medical attention rather than relying on homemade fluids.
Other Grains Work Too
Rice gets the most attention because it is widely available, inexpensive, and produces a mild-tasting liquid that sick people tolerate well. But it is not the only grain that works. A trial involving 257 boys with acute diarrhea and moderate to severe dehydration compared the standard WHO oral rehydration solution against cereal-based solutions made from maize, millet, sorghum, and rice. All four cereal-based solutions performed as well as the glucose-based standard in treating the diarrhea.6PubMed. Cereal based oral rehydration solutions
If you do not have rice on hand, you can make a similar starchy rehydration liquid by boiling any of those grains in extra water. The key ingredient is the starch, not something unique to rice. Maize porridge water (known as “ogi” water in parts of West Africa) and barley water (common in parts of the Middle East and South Asia) follow the same principle. The preparation method is identical: boil the grain in several times its volume of water, strain, salt, and cool.
How Much to Drink and How Often
For adults, aim to sip about a cup (roughly 200 to 250 mL) after each loose stool, plus additional fluid between episodes to stay ahead of losses. You do not need to drink it all at once. Small, frequent sips are easier on a churning stomach than large gulps. Over the course of a day with active diarrhea, an adult might drink a liter or more of rice water alongside other clear fluids.
For children, the general guideline from global health organizations is to offer 50 to 100 mL of oral rehydration fluid after each watery stool for children under two, and 100 to 200 mL for older children. Rice water follows the same dosing pattern. A teaspoon or tablespoon at a time is fine for toddlers who resist drinking. If your child vomits it back up, wait 10 to 15 minutes and try again with smaller amounts.
Do not rely exclusively on rice water for more than 24 to 48 hours without resuming a more complete diet. Prolonged diarrhea depletes potassium, zinc, and other nutrients that rice water does not meaningfully provide. Resume bland solid foods as soon as they can be tolerated, and consider a zinc supplement for children if diarrhea persists, as the WHO recommends zinc alongside oral rehydration for children under five.
Storage and Spoilage
Rice water spoils faster than you might expect. At room temperature, bacteria begin multiplying within a few hours, especially in warm climates. If you make a batch in the morning, use it by the end of the day. Refrigerated rice water keeps for about 24 hours. Give it a smell check before using; if it smells sour or fermented, discard it and make a fresh batch. You can reheat refrigerated rice water gently before serving, but bringing it to a full boil again is not necessary as long as the water used in the original preparation was safe.
That spoilage timeline is worth taking seriously because the whole point of the remedy is to treat an illness that dehydrates you. Drinking contaminated rice water could add a new infection on top of the one you already have. In situations where refrigeration is unavailable, make smaller batches more frequently rather than preparing a large quantity at once.
A Note on Arsenic in Rice
Some readers may have heard that rice contains arsenic and wonder whether rice water concentrates it. Rice does absorb inorganic arsenic from soil and water more readily than many other grains, and cooking methods affect how much ends up in the final product. Research comparing cooking methods found that washing rice before cooking and using excess water (which is essentially how you make rice water) removed roughly 54 to 58% of inorganic arsenic from white and brown rice.7Science of The Total Environment. A comparison of the effects of two cooking methods on arsenic species and nutrient elements in rice That arsenic goes into the cooking water, which in normal cooking you would drain off. When you are drinking the cooking water as a remedy, some of that arsenic is coming along for the ride.
For short-term use during an acute illness lasting a few days, this is not a meaningful health risk. The arsenic levels in a few cups of rice water are far below what would cause acute toxicity, and the benefit of staying hydrated during diarrhea vastly outweighs the trace exposure. The concern becomes more relevant if someone were drinking rice water daily as a routine beverage for weeks or months, which is not what this remedy calls for. If you live in an area where arsenic contamination of water or soil is a known issue, using well-rinsed rice and clean cooking water helps minimize the amount that ends up in the final liquid.
When to Skip the Home Remedy and Get Help
Rice water is a first-line stopgap, not a treatment for every type of diarrhea. Seek medical care rather than managing at home if you or your child has any of the following:
- Bloody stools: this suggests a bacterial infection like shigella or a more serious condition that may need antibiotics.
- High fever: a temperature above 102°F (39°C) alongside diarrhea, especially in young children or elderly adults, warrants evaluation.
- Signs of severe dehydration: dizziness when standing, very dark urine, confusion, or rapid heartbeat. Severe dehydration often requires intravenous fluids that no home remedy can substitute for.
- Duration beyond three days in adults or one day in infants: persistent diarrhea may signal an infection or condition that needs diagnosis and targeted treatment.
- Underlying health conditions: people with diabetes, kidney disease, or compromised immune systems should consult a healthcare provider early rather than self-managing with home fluids.
Rice water buys you time and comfort. It does not diagnose the cause of the diarrhea, and some causes, such as Clostridioides difficile infection, parasitic illness, or inflammatory bowel disease flares, require specific medical treatment.
Fermented Rice Water Is a Different Thing
Some wellness sources conflate plain rice water with fermented rice water, which is a different preparation with different properties. Fermented rice water is made by leaving cooked rice soaking in water overnight or longer at room temperature, allowing naturally present bacteria to colonize the liquid. Research has identified multiple species of lactic acid bacteria, including Lactobacillus fermentum and Lactococcus lactis, growing in overnight-fermented rice water, along with more than 200 metabolites that may support gut cell health.8PubMed Central. Postbiotics of Naturally Fermented Synbiotic Mixture of Rice Water Aids in Promoting Colonocyte Health
Fermented rice water is a traditional food in parts of India (known as “pazhankanji” in Kerala or “pakhala” in Odisha) and other cultures. The probiotic angle is interesting for general gut health, but during an active diarrheal episode it is not the right choice. The bacterial load in a homemade ferment is unpredictable, and introducing live bacteria into an already-inflamed gut can worsen symptoms. Stick with freshly prepared, non-fermented rice water while you are sick. Save the fermented version for when your stomach has settled, if you are curious about its probiotic properties.