Good & Bad Bacteria

The role of probiotics in gastrointestinal health.

Bacteria - Why the Bad Rap?

How important are bacteria to our lives? Judging from reports about outbreaks like skin-eating Streptococci and an E. coli outbreak that causes diarrhea and shuts down the kidneys, it would seem as though all bacteria are evildoers.

Even some research done here in our lab may have contributed to the misconception that all bacteria are “bad bacteria.” When we studied Houston babies with colic, which is characterized by crying and fussing for more than three hours a day in infants between 3 weeks and 3 months of age, we found a high prevalence of the bacterial strain Klebsiella.

Interestingly, the colicky babies showed a lower bacterial diversity in their stools than the infants without colic. This is important because it underscores the need for having a good balance of bacteria in our digestive systems to maintain gastrointestinal health. This is where probiotics can play a role.

Probiotics: The Good Bacteria

We have ten to 100 times more bacterial cells than human cells in our bodies. The medical profession is increasingly recognizing that certain bacteria provide health benefits. These bacteria help us grow normally and fight off the occasional harmful bacteria we may encounter. In fact, reduced bacterial diversity has been linked to a number of digestive disorders, including food allergies, celiac disease, obesity and inflammatory bowel disease. What we don’t know is if this reduced diversity is the cause or the effect of these conditions.

By definition, probiotics are live microorganisms that when taken in adequate quantity confer a health benefit to the host. These good bacteria are readily available and included in items such as yogurts, fermented milk products and probiotic supplements. They are also added to some infant formulas and even to vitamins.

However, some concerns are linked with probiotics. For one thing, they’re frequently lumped into one general category and often we don’t know the optimal probiotic strain for a given condition, the proper dose or even the safety profile. Some strains have been reported as causing gas and diarrhea and, on rare occasion, bloodstream infections and heart valve infections. Furthermore, most probiotics on the shelf are considered food additives and are not regulated by the Food and Drug Administration.

Probiotics and Gastrointestinal Symptoms

That being said, doctors are very interested in probiotics because of their possible health benefits. In humans, they may actually prevent the serious condition in newborns called necrotizing enterocolitis, a potentially life-threatening inflammation in the intestines. Pediatricians envision a day when we’ll be able to prescribe different probiotics for various conditions, just as we now prescribe different antibiotics. Hundreds of publications are coming out each year in which researchers are looking to determine what role probiotics will have in human disease.

There is currently a growing amount of solid, research-backed news about the benefits of probiotics in humans. The strongest evidence is that they lessen the severity and duration of watery diarrhea, with patients having viral diarrhea responding best. Evidence is relatively strong that probiotics decrease symptoms of irritable bowel syndrome, prevent necrotizing enterocolitis and reduce rectal bleeding in those with ulcerative colitis. Emerging evidence also suggests that probiotics may be effective in lessening crying time in infant colic and preventing the onset of allergic diseases, such as eczema and asthma. While more research needs to be done, this is all exciting news.

In my own clinics, I often use probiotics for babies with diarrhea that lasts up to two weeks and for babies with colic. The best tested probiotics in pediatric diarrhea studies are Lactobacilli (L. reuteri Protectis in BioGaia Protectis Baby drops and Lactobacillus GG in Culturelle powder) or a yeast called Sacchromyces boulardii (Florastor).

Currently, the only published studies of a probiotic for infants with colic used BioGaia’s L. reuteri Protectis in drop form. This strain is adapted from human breast milk cultures and, therefore, can be viewed as natural.

Irritable bowel syndrome (IBS) is one of the most common conditions facing older children and adults. It is characterized by abdominal pain often relieved by defecation and/or associated with a change in the texture of the stool, with lumpy stools or with incomplete evacuation. Sixteen studies have shown that probiotics improve gas symptoms and abdominal pain in IBS patients. However, selecting a probiotic for IBS can be a challenge. Many studies used probiotics that have a combination of different bacteria, and certain strains seemed to perform better than others. The magnitude of the effect is unclear. In my experience, they can be helpful in IBS. But low-dose antidepressants may be more effective, although they come with more side effects.

While much research has yet to be done on probiotics, the future of gastrointestinal health seems brighter because of this good bacteria. Stay posted for how probiotics may help your family.