If you're looking for relief from tummy trouble, you may want to consider trying helpful bacteria and yeast called probiotics.
Millions of friendly bacteria live in your intestines, and they're important for your digestion. But diarrhea can throw the microbes in your gut off balance. Probiotics may help get things back on track.
You can find probiotics in certain foods, like yogurt, and they also come in the form of supplements. Not all probiotics can ease diarrhea, though, and some help only certain types of diarrhea. So which ones can help, and when?
Kids and Diarrhea
Some of the best proof that probiotics work comes from studies of diarrhea in children, especially when it's caused by rotavirus. Probiotics might cut bouts of infectious diarrhea by half a day to about 2 days.
Some research shows that the bacteria strains most likely to help are Lactobacillus reuteri, Lactobacillus rhamnosus, and the probiotic yeast Saccharomyces boulardii, although other strains might be useful. A mix of a few different probiotics may also treat this type of diarrhea.
Diarrhea From Antibiotics
Antibiotics kill the germs in your body that make you sick, but they also kill some of the good bacteria. This can upset the normal balance in your intestines, leading to diarrhea.
Studies of children and adults show that you may cut your chances of having diarrhea if you take probiotics before and during treatment and several days after stopping your antibiotics. Saccharomyces boulardii and some strains of lactobacillus can work.
When you're away from home, you may get diarrhea when you eat or drink contaminated food or water.
There's no hard proof that probiotics work for this problem. Some research shows they help travelers avoid this kind of diarrhea, but other studies show there isn't any benefit. The strongest evidence points to help from Bifidobacterium bifidum, Lactobacillus acidophilus, and Saccharomyces boulardii.
Diarrhea Caused By C. difficile
An infection with C. difficile bacteria causes severe and sometimes life-threatening diarrhea and inflammation in the colon, called colitis. Probiotics may keep you from getting this germ. And there's some evidence they might stop the problem from coming back. That's important, since repeat infections become hard to control.
Scientists have done many studies of Saccharomyces boulardii against this type of bacteria. It appears to help, especially when combined with lactobacillus strains.
Inflammatory Bowel Disease
Probiotics may help treat ulcerative colitis, a form of inflammatory bowel disease (IBD). Some studies show probiotics may also help treat Crohn's disease, the other form of IBD, but the results aren't as strong.
Where to Find Probiotics
Most health food stores stock dozens of brands of probiotic foods and supplements, like yogurts or dairy drinks, capsules, powders, and liquids.
Look for probiotics with a specific type of bacteria that's been tested and found to work. Make sure the product has a Good Manufacturing Practices (GMP) seal. Choose products that say that they still work "through end of shelf life" rather than "at time of manufacture."
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