Some folks run to the bathroom multiple times a day. These poor souls know the gas stations and fast food joints with clean restrooms along their commute to and from work, and their unpredictable bowels might figure prominently in their social schedule. How long can they safely be away from a bathroom? On the other hand, there are people who go so infrequently that it would be a welcome and most happy development if they suddenly had to stop to use a restroom on their way to somewhere. The former group can take various anti-diarrheal pills and slurries to ward off the dire emergencies they may be all too familiar with, while the latter group can turn to laxatives, prune juice, or maybe a large amount of stool-softening sugar-free chocolate!

A quick perusal of drug store shelves is all that’s required to see that we are in the midst of an epidemic of intestinal dysfunction. There are things to help people who go too frequently, and things to help people who don’t go frequently enough. Whether it’s diarrhea or constipation, more and more it seems like an elusive holy grail to have regular bowel movements consisting of well-formed and easy-to-pass stools. Is there anything people can do to make their bathroom time less worrisome and more pleasant?

Indeed, probiotics may be beneficial for individuals with various forms of intestinal distress. To be fair, studies evaluating probiotics for this purpose have had mixed findings. Part of this owes to varying efficacy among different bacterial strains, and it may also be that some people respond to certain strains, and other people would respond to different ones. So it’s not so straightforward and simple to conduct research in this area, but overall, the weight of the evidence indicates that probiotics can offer great help.

A meta-analysis of randomized controlled trials looking at the effects of probiotics on functional constipation in adults found that Bifidobacterium lactis significantly reduced intestinal transit time (ITT), increased bowel movement frequency, and improved stool consistency. Another meta-analysis confirmed these findings, even echoing that B. lactis seems more effective than certain other bacterial strains. A third meta-analysis also found the most substantial benefits from B. lactis, while also noting that the effects were greatest in women, and in subjects with a higher mean age.

One analysis found that bifidobacteria and lactobacilli were both effective for decreasing ITT ad increasing stool frequency in constipated adults. In discussing the many problems with conducting this kind of research, the researchers pointed out that different studies define or classify constipation differently. Some determine constipation by subjects self-reporting; some use physician determination; others use official Rome diagnostic criteria. The degree to which someone is actually constipated—or the extent to which constipation differs from one subject to another—may factor in whether various probiotics are effective, and to what degree.

Regarding the other end of things—no pun intended—it’s well-known that antibiotics may result in diarrhea, likely owing to disruption of the intestinal microbiota. A 2015 Cochrane review of RCTs evaluating the efficacy of probiotics for prevention of antibiotic-associated diarrhea (AAD) in the pediatric population (age 0-18) determined that Lactobacillus rhamnosus or Saccharomyces boulardii at 5-40 billion colony-forming units per day would be an appropriate course of treatment. In analyzing the data, the study authors found that the incidence of AAD in the probiotic group was 8% (163/1992 subjects) compared to 19% (364/1906) in the control group. Importantly, the researchers found that of the 16 trials that reported on adverse events, none of the adverse or serious events were attributed to the probiotics. All adverse events, such as rash, nausea, gas, flatulence, abdominal bloating or pain, vomiting, and more, were in the placebo, standard care, or no treatment groups.

A meta-analysis looking at probiotics for AAD in children and adults found that AAD was present in 17.7% in the control group, but only 8.0% of the probiotic group. Like the Cochrane review, this analysis also determined that L. rhamnosus and S. boulardii may be the most effective organisms for this particular purpose. The conclusion says it all: “Using probiotics for the prevention of antibiotic-associated diarrhea reduces the risk of AAD by 51% (RR 0.49; 95% CI 0.36 to 0.67)…”

It’s fascinating that probiotics can help both constipation and diarrhea. It seems that these friendly organisms may normalize gut flora, similar to how adaptogenic herbs help normalize hormone responses, increasing what should be increased and decreasing what should be decreased.

By Amy Berger, MS, CNS

Related Nutrient Roundtable: Probiotics: Featuring ProbioMed™