Yogurt has long been a folk remedy for the problem in places like India, and experts suspected those folks were on to something. They just weren't sure.
So, the authors of an article appearing in the April issue of Pediatrics reviewed nine studies on the subject, using a particular statistical technique called a meta-analysis to summarize the results of the different studies."It is kind of a way to combine a lot of studies," explains Dr. Cornelius Van Niel, a study author and a clinical instructor in the department of pediatrics at the University of Washington at Seattle. "Individually, you would say, 'That's interesting, but I don't know if that's enough to change my practice.'" Collectively, the studies add up to a powerful argument in favor of yogurt's Lactobacillus as a treatment for diarrhea.
"It clearly helps, but it's not a panacea and it requires, in the studies that were done, adherence to protocol several times a day," says Dr. Mitchell Cohen, a professor of pediatrics at Cincinnati Children's Hospital Medical Center.
Some 21 million to 37 million episodes of diarrhea occur annually among the 16.5 million children under the age of 5 in the United States. The condition leads to 3 million physician's visits every year and 163,000 hospitalizations -- or 13 percent of all hospital stays for children in this age group.
Although rarely fatal in this country, infectious diarrhea does lead to a significant number of deaths in developing countries.
"Lactobacillus may prove more important in developing countries and in parts of Europe to prevent prolonged diarrhea, which is an uncommon occurrence in the U.S.," Cohen says.
The first line of treatment for infectious diarrhea in the United States is to make sure the child stays hydrated. "You avoid dehydration, and wait it out," Van Niel says. "There are very few cases where antibiotics are beneficial, and they are usually harmful."
According to Van Niel and his colleagues, Lactobacillus is not commonly prescribed in this country.
"It may be because it's not a traditional medication and it's more of a complementary, integrative approach, and that's still not thought of first by traditional Western doctors," Van Niel says.
Although Lactobacillus is found in yogurt, most practitioners who prescribe it prefer it in tablet or granule form, which can be mixed into cereal or milk.
However, yogurt is "worth a try," Van Neil says. The main downside is not knowing how many colony-forming units are in a particular product. The studies showed Lactobacillus seemed to be most effective when more than 10 billion colony-forming units were consumed in the first 48 hours. Lactobacillus therapy also appeared to be effective for diarrhea caused by a variety of pathogens.
Better yet, it's relatively cheap, with a 48-hour course costing about $10 and, according to the article, saving about 17 hours in caring for a sick child.
Choosing Lactobacillus does not mean ignoring the very real problem of dehydration. Getting back to work a half day early may be worth it, but only if the family can afford both the Lactobacillus and liquids to hydrate the child.
"You don't want to have people who have to choose between hydration and Lactobacillus," Cohen says.