2. Food intolerance
Diarrhea can also be caused by certain foods which the body may have trouble digesting. These typically include dairy products and artificial sweeteners. Undigested food-induced diarrhea can cause symptoms like nausea, cramping, gas and loose stools within half an hour to two hours of having a meal.
For lactose intolerant individuals, some are able to tolerate small amounts of milk in tea or coffee without getting their stomach upset while others can consume yogurt or cheese in restricted amounts, products that have less lactose than milk.