Many studies have shown that probiotics reduce diarrhea associated with taking antibiotics in both adults and children. In fact, it is common for physicians and pharmacists to recommend eating a probiotic-fortified yogurt every day during a course of antibiotics to prevent diarrhea. More research is needed to determine which probiotics are associated with the greatest effect for specific antibiotics.
Once GI experts realized there is more to the lower gut than first assumed, the push to understand the diverse roles these bacteria play became urgent. Many mysteries still need solving, but clinical evidence increasingly indicates that people in good health should optimize lower gut bacteria. You can accomplish this by eating prebiotics to encourage the growth of your existing gut microbes, and probiotics to add to the ones that are already there.
Prebiotics and probiotics have been trending for a while now, but lately they’re getting even more attention — and showing up in more and more products, from packaged foods (pizza crust!) to topical skin-care products. It’s no surprise consumers are interested: As scientists learn more about the trillions of bacteria that inhabit our bodies and the role they play in our health, some have touted beneficial bugs as a cure-all for digestive distress and other health problems.
Even if some of the bacteria in a probiotic managed to survive and propagate in the intestine, there would likely be far too few of them to dramatically alter the overall composition of one's internal ecosystem. Whereas the human gut contains tens of trillions of bacteria, there are only between 100 million and a few hundred billion bacteria in a typical serving of yogurt or a microbe-filled pill. Last year a team of scientists at the University of Copenhagen published a review of seven randomized, placebo-controlled trials (the most scientifically rigorous types of studies researchers know how to conduct) investigating whether probiotic supplements—including biscuits, milk-based drinks and capsules—change the diversity of bacteria in fecal samples. Only one study—of 34 healthy volunteers—found a statistically significant change, and there was no indication that it provided a clinical benefit. “A probiotic is still just a drop in a bucket,” says Shira Doron, an infectious disease expert at Tufts Medical Center. “The gut always has orders of magnitude more microbes.”
Taking probiotics can also help keep your urinary system working properly. While you might think that yeast imbalances or urinary tract issues are primarily women's problems, both are common in men as well, especially in those whose bacterial balance is off-kilter. Taking probiotics can help address these issues by encouraging the growth of good bacteria to crowd out unwanted yeast.10
“Aside from the beneficial probiotics, this has plant-based compounds like ginger to soothe upset stomachs and support healthy digestive function,” says Beth Warren, MS, RDN, a dietitian in New York City. It also has prebiotics, which encourage the growth of healthy bacteria that support the well being of pregnant and breastfeeding women, she explains. “The formula has L. rhamnosus HN001, which has been shown to support the child’s developing immune system during the last trimester and early breastfeeding period.”
Here they perform a dual role: firstly, a probiotic supplement can ensure that the gut flora remains healthy and well-balanced. This could speed up the return to normal defecation. Secondly, serious diarrhoea can cause the gut flora to become depleted, which can slow recovery. In some cases, symptoms may even worsen. Once again, probiotic supplements can help you to regain a healthy balance of intestinal bacteria.