Plain potatoes are one of the better foods you can eat during a bout of diarrhea. They’re easy to digest, rich in potassium (which you lose quickly through fluid loss), and contain soluble fiber that actually helps absorb excess water in the gut. Boiled or mashed potatoes without heavy toppings are a safe, practical choice while your digestive system recovers.
Why Potatoes Work During Diarrhea
Potatoes are a bland, starchy food that places very little stress on an irritated digestive tract. The soluble fiber in potatoes absorbs fluid in the intestines, which can help firm up loose stools. This is the opposite of insoluble fiber, found in things like raw vegetables and whole grains, which stimulates the bowel and can make diarrhea worse.
Potatoes also deliver potassium and small amounts of sodium, two electrolytes that get depleted fast during diarrhea. A medium boiled potato provides roughly 400 to 500 mg of potassium, making it a useful food for replenishing what your body is losing. And because potatoes are naturally low in fat and free of strong flavors, they rarely trigger further irritation.
University of Pennsylvania dietary guidelines for managing diarrhea specifically list boiled potatoes as a food high in soluble fiber and mashed potatoes as one of the best-tolerated foods when diarrhea is severe.
How to Prepare Potatoes When You Have Diarrhea
Preparation matters more than you might think. The goal is to keep the potato as simple and easy to digest as possible.
Peel the skin off before cooking. Potato skins contain insoluble fiber, which adds bulk and stimulates bowel activity. That’s normally a good thing, but during diarrhea it can speed up digestion and worsen symptoms. General guidance from low-fiber diet protocols is to peel, seed, and cook vegetables until they’re soft.
Boiling and mashing are your best cooking methods. Baking is fine too, as long as you skip the skin. Frying is not. Greasy, fried foods are harder to digest and can aggravate an already sensitive gut. That means french fries, hash browns, and potato chips are all off the table until you’ve recovered.
Toppings to Avoid
A plain baked potato is helpful. A loaded baked potato is not. Butter, sour cream, cheese, and heavy sauces add fat and dairy, both of which can worsen diarrhea. Spicy seasonings are also worth skipping. Penn State Health guidelines recommend avoiding greasy, fried, and spicy foods during diarrhea and limiting milk or milk products to no more than two cups a day. A small amount of salt is fine and can even help with electrolyte replacement, but keep everything else minimal.
White Potatoes vs. Sweet Potatoes
Both are reasonable choices, but they have slightly different strengths. White potatoes are a classic bland food and a reliable source of soluble fiber. Sweet potatoes are softer on the digestive system once cooked and are easier on digestive enzymes. They also contain compounds that support gut health and may help improve diarrhea directly.
If you’re choosing between the two, either will work. Sweet potatoes may have a slight edge for digestive comfort, but the most important factor is how you prepare them: peeled, well-cooked, and without rich toppings. Both should be soft enough to mash easily with a fork before you eat them.
The Resistant Starch Bonus
Here’s something worth knowing for the recovery phase. When you cook potatoes and then let them cool completely, some of the starch transforms into what’s called resistant starch. This type of starch isn’t digested in your small intestine. Instead, it passes to the large intestine, where gut bacteria ferment it and produce short-chain fatty acids. These compounds lower inflammation and support immune function, both of which help your gut heal after a diarrhea episode.
Research from UCLA Health shows that each day of cooling (up to about four days after cooking) increases the percentage of resistant starch in the potato. So eating a cold potato salad (dressed simply, with a little salt and olive oil) a day or two into recovery could give your gut microbiome a useful boost. This isn’t necessary during the worst of your symptoms, but it’s a smart strategy as you transition back to normal eating.
Where Potatoes Fit in a Recovery Diet
You may have heard of the BRAT diet: bananas, rice, applesauce, and toast. It’s been recommended for decades as a go-to during stomach illness, though there are no studies comparing it to other approaches. Harvard Health notes that there’s no need to restrict yourself to just those four foods. Boiled potatoes, brothy soups, oatmeal, crackers, and unsweetened dry cereals are all easy to digest and belong in the same category.
Sticking with bland, low-fiber, low-fat foods like potatoes for a day or two makes sense while symptoms are active. As things improve, gradually reintroduce other foods. Adding small amounts of lean protein (plain chicken, eggs) and well-cooked vegetables without skins helps bridge the gap back to your normal diet without overwhelming your digestive system.
Throughout the process, staying hydrated matters just as much as food choices. Water, broth, and oral rehydration solutions replace the fluids and electrolytes your body is losing. Potatoes help with the food side of recovery, but they can’t substitute for adequate fluid intake.