Bland, low-residue foods that are easy to digest and unlikely to pull extra water into your gut are the safest choices during a bout of diarrhea. White rice, plain toast, bananas, and boiled potatoes top the list, while greasy meals, sugary drinks, caffeine, and sugar-free candies sit squarely on the “worst” side. But the real story is more nuanced than any short list can capture, because the foods that help or hurt depend on whether you’re dealing with a 24-hour stomach bug or something more persistent, and because what you drink matters at least as much as what you eat.
The Foods That Genuinely Help
You’ve probably heard of the BRAT diet: bananas, rice, applesauce, and toast. It’s been recommended for decades, and while it’s fallen out of favor as a strict protocol (more on that shortly), the individual foods in it still make sense. White rice and plain toast are low in fiber, gentle on inflamed intestines, and provide glucose your body needs for fluid absorption. Bananas bring potassium, which you lose fast during diarrhea, and they contain pectin, a soluble fiber that can gel up in your colon and add bulk to watery stool.
Green (unripe) bananas deserve special mention. In children with persistent diarrhea, green banana reduced stool weight by about half, and the effect was strongly linked to improvements in intestinal permeability, meaning the gut lining was literally sealing itself back up faster.1PubMed. Green banana and pectin improve small intestinal permeability and reduce fluid loss in Bangladeshi children with persistent diarrhea Pectin from other sources (apples, for instance) works through a similar mechanism. In the colon, pectin forms a gel with calcium ions, which creates more solid fecal matter and can stimulate the normal muscular contractions that move stool along at a healthy pace.2PubMed. Undigested low-methoxy pectin prevents diarrhea and induces colonic contraction during liquid-diet feeding in rats
Beyond the BRAT staples, other safe options include plain crackers, boiled or baked potatoes without butter, skinless chicken breast, and clear broth-based soups. These foods share two properties: they’re low in fat, and they don’t contain much insoluble fiber or poorly absorbed sugars. The goal isn’t nutrition optimization. It’s giving your gut something to work with that won’t make things worse.
Why Rehydration Matters More Than Food Choices
Honestly, what you drink during diarrhea probably matters more than what you eat. The main danger from acute diarrhea isn’t calorie loss; it’s dehydration and electrolyte depletion. Your small intestine has a built-in mechanism where sodium and glucose are absorbed together through the same transporter, and water follows along. Research has shown that roughly 260 water molecules are pulled across the intestinal wall for every sugar molecule transported this way, accounting for an estimated five liters of water absorption per day under normal conditions.3PubMed Central. Cotransport of water by the Na+/glucose cotransporter
This is the entire basis for oral rehydration solutions. The sodium-to-glucose ratio in these drinks is calibrated to maximize this co-transport mechanism.4Scientific Reports. Potency of Oral Rehydration Solution in Inducing Fluid Absorption is Related to Glucose Concentration A commercial oral rehydration solution or a homemade one (water, salt, and a small amount of sugar) is the single most effective thing you can put in your body during diarrhea. Sports drinks aren’t ideal substitutes; many contain too much sugar and not enough sodium, which can actually worsen symptoms by increasing the osmotic load in your gut. Clear broths are a reasonable alternative because they provide both sodium and water in a form that’s easy to absorb.
Foods and Drinks That Make Diarrhea Worse
Some foods actively worsen diarrhea through specific, well-understood mechanisms. Knowing which ones and why helps you avoid them even in forms you might not expect.
Sugary Foods and Drinks
When your gut can’t fully absorb a sugar, it stays in the intestinal lumen and pulls water in after it through osmosis. This is osmotic diarrhea, and it’s the same principle behind why some laxatives work.5JCI Insight. Intestinal ion transport and the pathophysiology of diarrhea Fructose is one of the biggest offenders. A substantial portion of healthy people can’t fully absorb fructose when consumed in excess of glucose, and the consequences include increased water delivery to the colon and rapid fermentation by gut bacteria, producing gas and urgency.6PubMed. Fructose malabsorption and the bigger picture This is why apple juice, pear juice, and honey (all high in free fructose) are among the worst beverages you can choose during diarrhea.
Fruit juice in general tends to be problematic. Even beyond fructose, a diet high in poorly absorbed short-chain carbohydrates (sometimes grouped under the term FODMAPs) increases intestinal water output by roughly 20% compared to a low-FODMAP diet, with effluent volume rising by about 95 milliliters in controlled testing.7PubMed. Dietary poorly absorbed, short-chain carbohydrates increase delivery of water and fermentable substrates to the proximal colon That extra fluid is the last thing you need when your stool is already watery.
Sugar Alcohols and “Sugar-Free” Products
Sorbitol, xylitol, mannitol, and other sugar alcohols found in sugar-free gum, mints, and diet candies are classic osmotic offenders. They’re poorly absorbed by design, which is why they’re low-calorie, but that same property means they drag water into your intestines. The diarrhea they cause isn’t harmful to the gut lining itself, but it can be dramatic in volume.8PubMed Central. Gastrointestinal Disturbances Associated with the Consumption of Sugar Alcohols with Special Consideration of Xylitol: Scientific Review and Instructions for Dentists and Other Health-Care Professionals If you’re already dealing with diarrhea and chewing sugar-free gum throughout the day, that habit alone could be prolonging your symptoms.
Fatty and Greasy Foods
Fat has a complicated relationship with gut motility. When fat enters the small intestine, it triggers the release of cholecystokinin (CCK), a hormone that initially speeds up transit in the upper gut. There’s a counterbalancing opioid-mediated brake that slows things down later, but the net effect depends on the dose and context.9PubMed. Intestinal transit of fat depends on accelerating effect of cholecystokinin and slowing effect of an opioid pathway When your gut is already irritated and motility is already elevated, adding a heavy fatty meal tends to push things further in the wrong direction. Fried foods, rich sauces, fast food, and fatty cuts of meat are best set aside until you’ve recovered.
People who’ve had their gallbladder removed are especially susceptible to fat-related diarrhea, because bile acids are released continuously into the intestine rather than being stored and released on demand. If that applies to you, keeping fat intake low during a diarrheal episode is even more important.
Caffeine
Caffeine in isolation stimulates water and sodium secretion in the small intestine. In perfusion studies, caffeine solutions caused the jejunum to flip from net absorption to net secretion of both water and sodium.10Gastroenterology. Effects of caffeine and coffee on fluid transport in the small intestine Interestingly, the same research found that whole coffee didn’t cause the same secretory effect, suggesting other compounds in coffee partially counteract caffeine’s influence. Still, during active diarrhea, the safest bet is to skip caffeinated beverages entirely. They also have a mild diuretic effect, which works against your rehydration efforts.
Spicy Foods
Capsaicin, the compound that makes chili peppers hot, activates receptors in the gut lining and can increase motility and sensations of urgency. Research on people with diarrhea-predominant irritable bowel syndrome found that initial exposure to chili sensitizes these receptors, worsening symptoms, though repeated exposure over time eventually led to desensitization.11PubMed Central. Effects of Chili Treatment on Gastrointestinal and Rectal Sensation in Diarrhea-predominant Irritable Bowel Syndrome: A Randomized, Double-blinded, Crossover Study That long-term adaptation isn’t helpful when you’re in the middle of an acute episode. Avoid spicy food until your gut has calmed down.
The Dairy Question
Dairy is a gray area. Milk contains lactose, which requires a specific enzyme (lactase) to break down. If you normally tolerate milk fine, a small amount of dairy during mild diarrhea probably won’t cause problems. But here’s the catch: acute gastroenteritis can temporarily damage the brush border of your small intestine where lactase is produced. This means a stomach bug can give you a temporary form of lactose intolerance even if you’ve never had trouble with milk before. In children, this transient lactose intolerance is well-documented and typically resolves once the underlying infection clears.12PubMed Central. Lactose intolerance and gastrointestinal cow’s milk allergy in infants and children – common misconceptions revisited
Yogurt is a notable exception. The bacterial cultures in yogurt have already partially broken down the lactose, making it easier to digest. Plain, unsweetened yogurt is generally well tolerated during diarrhea and has the added advantage of delivering live bacteria that may help recovery, which brings us to probiotics.
Probiotics and Fermented Foods
Fermented foods like yogurt, kefir, and kimchi introduce live microorganisms into your gut. The evidence for probiotics in acute infectious diarrhea is encouraging, though the effect varies depending on the specific strain and the individual. A Cochrane review pooling data from thousands of patients found that probiotics shortened the average duration of diarrhea by about 25 hours and roughly halved the risk of diarrhea lasting four or more days.13PubMed Central. Probiotics for treating acute infectious diarrhoea The review also noted that probiotics appeared safe when used alongside rehydration therapy.
That said, the effect size varied considerably between studies, which means not every probiotic product will deliver the same benefit. Saccharomyces boulardii and Lactobacillus rhamnosus GG are the most studied strains for diarrhea. If you’re choosing between a probiotic capsule and a serving of plain yogurt, either is reasonable. Kombucha and other fermented drinks with added sugar, on the other hand, might do more harm than good because of the sugar content.
Don’t Fast — Eat Early
One of the most persistent myths about diarrhea is that you should “rest your gut” by not eating until symptoms pass. The evidence says the opposite. Fasting during acute gastroenteritis maintains increased intestinal permeability, meaning the gut lining stays leakier for longer. Children who continued eating during gastroenteritis (in addition to receiving fluids) had normal gut permeability on testing, while fasted children had significantly elevated permeability regardless of whether their fluid replacement was adequate.14Journal of Pediatric Gastroenterology and Nutrition. Intestinal Permeability Changes in Acute Gastroenteritis The takeaway is clear: early refeeding promotes faster gut repair.
You don’t need to force a full meal if your appetite is gone. Small, frequent portions of the bland foods described above are enough to give the gut the signals it needs to start healing. Starting with a few spoonfuls of rice or a quarter of a banana and building up gradually works well for most people. The old advice to progress from clear liquids to bland solids to a normal diet over several days is more conservative than necessary; most people can tolerate bland solids from the start.
Zinc and Micronutrient Losses
Diarrhea doesn’t just flush out water and electrolytes. It also depletes micronutrients, particularly zinc and copper, and this depletion can create a vicious cycle because zinc itself plays a role in strengthening the immune response and maintaining the intestinal lining.15PubMed Central. Effect of Zinc Supplementation in Children with Acute Diarrhea: Randomized Double Blind Controlled Trial A meta-analysis of 24 trials found that zinc supplementation reduced the duration of diarrhea by about 13 hours compared to placebo, and children receiving zinc were modestly but significantly more likely to have recovered by the last follow-up.16PubMed Central. Zinc supplementation for acute and persistent watery diarrhoea in children: A systematic review and meta-analysis
The World Health Organization recommends zinc supplementation for children with diarrhea in developing countries, where baseline zinc status tends to be low. For adults in well-nourished populations, the benefit of supplementation during a short bout of diarrhea is less clear. What is clear is that eating zinc-rich foods during recovery (lean meat, eggs, seeds, and legumes once you’re tolerating solids) helps replenish what you’ve lost.
Temperature of What You Eat and Drink
You might wonder whether the temperature of your food or drinks matters. There is some evidence that very cold beverages slow down gastric contractions. A study found that drinking water at 2°C reduced the frequency of stomach contractions compared to water at 60°C.17PubMed Central. The effects of water temperature on gastric motility and energy intake in healthy young men In theory, slowed gastric emptying could modestly reduce how quickly fluid reaches the intestine, giving the gut more time to absorb it. In practice, this effect is small enough that room-temperature or slightly cool drinks are fine. The important thing is to drink steadily and frequently, not to obsess over the thermometer.
Very hot foods can be soothing (warm broth, for instance), and there’s nothing wrong with them. The one practical consideration: if you’re already nauseous, extremely hot or extremely cold foods tend to be less well tolerated than things closer to body temperature.
A Quick-Reference List
Pulling this together, here are the best and worst choices during an active bout of diarrhea:
Foods and drinks that help:
- White rice: low fiber, easy to digest, provides glucose for fluid absorption
- Bananas: especially green/unripe ones, which contain pectin and replenish potassium
- Plain toast or crackers: simple starches that are gentle on the gut
- Boiled potatoes: without butter or cream, a good source of starch and potassium
- Clear broth: provides sodium, water, and a small amount of energy
- Plain yogurt: low in lactose, provides live cultures that may shorten illness
- Oral rehydration solution: the single most important thing to consume during diarrhea
- Skinless chicken or lean protein: once appetite returns, easy to tolerate
Foods and drinks to avoid:
- Fruit juices: high in fructose and osmotically active sugars
- Sugar-free gum and candy: sugar alcohols are potent osmotic laxatives
- Fried and greasy food: stimulates motility and is hard to digest
- Coffee and caffeinated drinks: caffeine promotes intestinal secretion
- Spicy food: capsaicin sensitizes gut receptors and increases urgency
- Milk: lactose may be temporarily harder to digest during gut inflammation
- Alcohol: irritates the gut lining and worsens dehydration
- Raw vegetables and high-fiber grains: insoluble fiber can accelerate transit
Food Safety During and After Recovery
If your diarrhea was caused by a foodborne pathogen, the last thing you want is to reinfect yourself or someone in your household. Many of the viruses that cause gastroenteritis (norovirus being the most common) are remarkably stable in the environment and can persist on surfaces and in improperly handled food.18PubMed Central. Foodborne viruses: an emerging problem While you’re symptomatic and for at least 48 hours after symptoms resolve, avoid preparing food for others if possible. Wash your hands thoroughly and often. Cook foods to proper temperatures, and be especially cautious with raw produce and ready-to-eat items that won’t be heated before serving.
When you’re stocking up on bland recovery foods, stick to items that require minimal preparation: pre-cooked rice, plain crackers, canned broth, and bananas that can be peeled without a cutting board. The fewer surfaces and utensils involved, the lower the risk of contaminating shared kitchen spaces.
When Your Diarrhea Isn’t a Simple Stomach Bug
Everything above assumes you’re dealing with a standard acute episode that will resolve within a few days. If your diarrhea persists beyond two weeks, the dietary approach shifts. Chronic diarrhea often has an underlying cause — lactose intolerance, celiac disease, inflammatory bowel disease, bile acid malabsorption, or a food sensitivity — and each of these calls for different dietary modifications.
For example, someone with celiac disease needs to eliminate gluten permanently, not just eat bland foods for a few days. Someone with bile acid malabsorption might benefit from a low-fat diet long-term. And for people with irritable bowel syndrome, a structured low-FODMAP elimination diet, guided by a dietitian, tends to be more effective than the vague advice to “eat bland.” If your symptoms keep coming back or never fully resolve, the right next step isn’t a better food list. It’s a conversation with a doctor to figure out what’s driving the problem.