Diarrhea is one of the most common health complaints. It can range from a mild, temporary condition, to a potentially life-threatening one. Globally, an estimated 2 billion cases of diarrheal disease occur each year, and 1.9 million children under the age of 5 years, mostly in developing countries, die from diarrhea. Diarrhea is characterized by abnormally loose or watery stools. Some people frequently pass stools, but they are of normal consistency. This is not diarrhea. Similarly, breastfed babies often pass loose, pasty stools. This is normal. It is not diarrhea.