Diarrhoea is any attack of frequent, watery stools.

Diarrhoea can be triggered by many different conditions. Acute diarrhoea is often caused by an infection and may require medical management. The primary role of nutrition in acute diarrhoea is to prevent depletion of fluid, sodium, potassium, and calories. Replenishment of all four has been achieved with “rehydration solutions” and with a variety of foods, from salted carrot soup to peeled scraped apple to rice gruel. However, diarrhoea severe enough to necessitate the use of rehydration solutions requires direct medical supervision. Therefore, nutritional approaches to overcoming depletion of fluid, sodium, potassium, and calories are not discussed here, but rather should be discussed with a doctor. Diarrhoea-induced low blood sugar, dehydration, or electrolyte imbalance can be serious or even life-threatening, particularly if prolonged in children.

A doctor should be consulted if diarrhoea continues for more than a few days, as it may indicate a more serious health condition. Diarrhoea alternating with constipation may be a sign of irritable bowel syndrome (IBS).