The best diet for diarrhea is generally a simple one made up of liquids and bland foods. Traditionally, the bananas, rice, applesauce, and toast (BRAT) diet is used for diarrhea, assuming there are no other symptoms or that all other gastrointestinal symptoms have stopped. All of these foods are gentle on the stomach and low in fiber, which can make diarrhea worse.

Replenishing fluids which may have been lost due to excessive fluid in the stools is the first step in any diet for diarrhea. This can be done by drinking plenty of water or commercially prepared re-hydration fluids. Sodas and other beverages should be avoided during this time because caffeine has a diuretic effect and has been linked to dehydration.
Those who have severe diarrhea or who are vomiting frequently in combination with loose stools may need to be hydrated using additional means. Herbs or medications may be used to prevent vomiting so that liquids stay down, or water pills can sometimes by inserted rectally. Taking baths can also help because some water absorbs through the pores of the skin. In very severe cases, fluids may need to be given intravenously in a hospital setting.

Aside from fluid intake, the most common diet for diarrhea combines various bland foods which are easily digested. The BRAT diet is one example of this, although it is not the only one. It is important to remember that any foods given should be low in dietary fiber. Dairy products are also irritating to the intestinal tract, so they should be avoided. Once the diarrhea has subsided and any other symptoms have gone, foods can slowly be introduced back into the diet. Grains and proteins should come first, followed by harder to digest fibrous fruits, vegetables, and dairy products. If diarrhea returns, discontinue eating the offending food. To determine which foods are causing problems, introduce only one new food back into the diet at a time.
Children should stay on the diarrhea diet for a little longer than adults to prevent a recurrence of symptoms. Most of the time, diarrhea is caused by eating a certain food or by a minor bacteria or viral infection and generally passes quickly. If symptoms persist, or diarrhea is accompanied by chills, body aches, vomiting, nausea, or fever, a doctor should be notified. Small children are especially at risk for dehydration, which can be a serious problem for childrenunder the age of five.