This Is How Long It Takes For Probiotics To Start Working

When you have diarrhea or indigestion, it makes sense to take probiotics to bring your gut back into balance. These dietary supplements contain live bacteria that help repopulate the gut, leading to a healthy microbiome. According to 2018 research presented in BMJ, the human gut is home to over 100 trillion microbes, such as fungi, bacteria, and viruses. Some of these microorganisms aid in digestion, support immune function, fight inflammation, and regulate metabolism. Low-fiber diets, antibiotics, and certain diseases can affect the microbiome, or gut flora, causing all sorts of issues. Probiotics can restore the delicate balance of good and bad bacteria in the gut, which may improve your overall health.

Probiotics have both immediate and long-term effects, depending on the product formula, dosage, bacterial strains, and other factors, explains a 2018 review published in PLoS One. For example, some probiotics are particularly effective at preventing travelers' diarrhea, while others work best for those with irritable bowel syndrome or inflammatory bowel disorders. 

Whichever probiotic you choose, they often take time to work, and their effects can be subtle at first. As gastroenterologist Kumkum Sarkar Patel told POPSUGAR, "There are no magic telltale signs that probiotics are working, but you may see an improvement in abdominal pain, bloating, inflammation, and weight." Over time, the good bacteria in probiotics can boost immune function and digestive health, increase your energy, and relieve constipation. But how long does it take for probiotics to start working? Let's see what the research says. 

What to expect when you take probiotics

Probiotic supplements contain different bacterial strains, such as Lactobacillus, Streptococcus, Escherichia, and Saccharomyces (per National Institutes of Health). Their efficacy and mechanism of action depend on the number and type of bacterial strains, among other aspects. Some types of probiotics, such as Lactobacillus GG, may relieve acute diarrhea in as little as five days, reports a 2012 clinical trial in Pediatric Emergency Care. Similarly, a 2015 study featured in Drugs in R&D noted that Saccharomyces boulardii, a probiotic yeast, can help treat acute diarrhea within three or four days.

These supplements may take longer to work for those with IBS, food allergies, or inflammatory bowel disease. In one study, IBS patients who took a multi-species probiotic formula experienced significant improvement within four weeks of treatment. Another study in the Journal of Clinical Gastroenterology found that both L. acidophilus and B. lactis can reduce bloating in people with functional bowel disorders within four to eight weeks. If you're allergic to dairy or other foods, you may need to take probiotics for several years to reap the benefits, according to 2018 evidence published in The World Allergy Organization Journal.

All in all, most probiotics can take anywhere between a few days and a few months to start working. If you have an acute condition like traveler's diarrhea or occasional constipation, you may begin to feel better within days. However, IBS and other chronic conditions require longer treatment.