If you've ever had a colicky baby or you know someone who has, you know how distressing it can be. Colic affects up to 28 percent of newborns and is one of the most vexing problems parents and pediatricians face in the first few months of life.
Colic is defined as intermittent bouts of prolonged, inconsolable crying with no specific cause, often lasting for hours each day. The cause remains unclear, even though colic has been studied for more than 40 years.
Some researchers feel that multiple factors contribute to colic, including allergies, prenatal and postnatal exposure to tobacco smoke, maternal anxiety and, finally, abnormal gastrointestinal function.
Intriguing research in the past five years suggests that an imbalance of bacteria in the gastrointestinal tract may be a significant culprit. Our intestines have lots of different bacteria, which in a healthy person live in balance with one another. This includes "friendly" bacteria like lactobacilli and bifidobacteria; these organisms are also called probiotics (they are "pro-life" rather than harmful to life).
Our GI tracts also contain some "unfriendly" bugs like E. coli, the bacteria that can cause severe diarrheal infections. Usually, however, there is a balance between the good and the bad, so that organisms like E. coli do not cause disease.
Some studies have suggested that infant colic is due at least in part to the overgrowth of E. coli in a baby's intestines, contributing to a low-grade inflammation or infection; the cause of this is not always known. Restoring balance with healthy probiotic bacteria may thus help reduce E. coli levels and improve symptoms like colic, diarrhea and constipation.
A recent study in the journal Pediatrics examined the effect of a specific probiotic, Lactobacillus reuteri, on colicky, breast-fed babies ages 2-16 weeks. Forty-six infants were divided into two groups -- 25 received the L. reuteri probiotic for 21 days; the other 21 got a placebo. The mothers also avoided cow's milk during the study.
At the start of the study, the infants were similar in colicky crying time -- 370 minutes a day in the reuteri group vs. 300 in the placebo group. By the end, the infants getting the probiotic dropped their crying time to 35 minutes a day vs. 90 minutes for the placebo group. In addition, 24 babies in the reuteri group had at least a 50 percent reduction in colic vs. only 15 percent in the placebo group. Infants getting the probiotic also had a significant reduction in E. coli in their stool and an increase in lactobacilli.
The probiotic caused no adverse effects in the infants. The researchers speculated that those getting the placebo might have improved because colic tends to lessen as an infant's GI tract matures. The authors concluded that the changes in gut bacteria induced by the L. reuteri likely accounted for the reduction in colic.
A 2007 study in Pediatrics also found that L. reuteri was very effective in reducing colic. Other studies have suggested that probiotics modulate immune function and restore healthy gut function, and they may also play a role in treating several other illnesses in children and adults, including other intestinal infections, allergies, dermatitis and depression.
This data are very encouraging, especially since no other effective treatments are available for colic. While L. reuteri does appear to be safe in infants, we encourage you to speak with your pediatrician before trying this therapy, especially since the FDA does not regulate over-the-counter products for purity or safety.
Explore further: What else may probiotics do in adults?