Last Reviewed: August 2013
Get the Facts
Make An Informed Decision
About diarrheal infections
Babies don’t get to choose whether they are fed breast milk or formula, but you do. And since your choice can affect your child’s healthy development you need to get all the facts.
Breastfed babies are at lower risk for various infections, including diarrhea or gastrointestinal infections.
Diarrhea is common in infants and children. In the United States, it is estimated that in children under five years old, each child would have an average of at least one episode per year.
While a diarrheal infection is generally brief, it may also be accompanied by stomach pains, cramps, vomiting, loss of appetite, nausea and/or fever.
In left untreated, diarrhea can be dangerous. Diarrhea may cause dehydration which can lead to serious illness and hospitalization.
What causes diarrhea?
All breastfed babies naturally have loose stools. Diarrhea is different. It is caused by an infection and can be severe, with frequent watery stools.
A gastrointestinal infection or gastroenteritis (also known as ‘gastro’ or ‘stomach flu’) involves both the stomach and the small intestine and usually results in acute diarrhea. This type of infection in infants is most commonly caused by viruses or bacteria. The rotavirus is the most common cause of acute diarrhea among children between six months and two years of age.
How does breast milk protect children against diarrhea?
While researchers do not yet understand the exact way in which breastfeeding protects against these types of infections, there is evidence that specific compounds in breast milk may be the reason. Some of these compounds include SigA (an important immunoglobulin), lactoferrin (a whey protein) and lysozyme (an enzyme).
Lysozyme and lactoferrin work together to destroy invading viruses and bacteria. While lactoferrin takes away nutrients from viruses and bacteria, lysozyme enzymes attack their cell walls. The immunoglobulin SigA coats the lining of the intestines and stomach to prevent any remaining viral/bacterial cells from attaching onto the cell walls of the baby’s gut.
The more of these substances infants receive, the lower their risk of having a gastrointestinal infection. This protective effect of breast milk appears to last up to two months after weaning. Formula does not contain any of these substances.
About the scientific research
What kind of scientific review was this?
This was a systematic review of 16 studies (12 prospective cohort studies, two retrospective cohort studies and two case-controlled studies) involving 5,473 children, 504 children and 331 pairs respectively. The studies reviewed were conducted in developed countries among children with no other medical condition.
The researchers examined the relationship between breastfeeding and development of gastrointestinal infections in children less than one year of age from developed countries.
The studies were adjusted for other factors which could influence a child’s risk of having a diarrheal infection, such as: gender, race, maternal education, family living standards, marital status, paternal social class and/or parental smoking.
What were the results of the review?
Evidence from the three higher quality studies that controlled for other factors, suggest breastfeeding is associated with a reduction in the risk of gastrointestinal infection.
Is there an opportunity for more research?
Yes, there is an opportunity to investigate further the extent breast milk protects against gastrointestinal infections. Future research should clearly differentiate between infants who were exclusively breastfed and infants who were ever breastfed. This is because studies examining other infections, such as otitis media (ear infection), found a connection between exclusive breastfeeding and lower rates of ear infections.
What were the results of the review?
The review determined breastfeeding is associated with a significant reduction in the risk of non-specific gastroenteritis.