Table of ContentsView AllTable of ContentsBenefitsWhen to Take ProbioticsSide EffectsForms of Supplements
Table of ContentsView All
View All
Table of Contents
Benefits
When to Take Probiotics
Side Effects
Forms of Supplements
Nor is it entirely clear who should use them. Beyond digestive impacts, the benefits of probiotic types (strains) that may aid health in males, such as for testosterone levels, or in females (such as for vaginal health) are also controversial.
In the United States, the Food and Drug Administration (FDA) does not regulate supplements the way it regulates prescription drugs. That means some supplement products may not contain what the label says. Whenchoosing a supplement, look for independently tested products and consult a healthcare provider, registered dietitian nutritionist (RD or RDN), or pharmacist.
d3sign / Getty Images
How Are Probiotics Good for You?
Probiotics are sold in many formulations and products. How they may benefit health is an active area of study, but there aren’t many conclusions available yet.
The human body has many different types of microorganisms that live on and inside it, called themicrobiome.A probiotic supplement aims to change the makeup of the microbiome to provide some health benefits. The challenge is in knowing which probiotic is helpful and for which health problem.
There is little in the way of guidance available onwho should take probioticsand when. However, people taking antibiotics, having a gastrointestinal infection, or having digestive symptoms (such asdiarrheaorconstipation) may want to talk to a healthcare provider about starting a probiotic.
Preventing Antibiotic-Associated Diarrhea
Some people may have diarrhea after taking antibiotics for an infection. This is because an antibiotic may kill the good bacteria of the gut microbiome along with the bacteria causing the infection. This results indysbiosis, which is an imbalance in the gut microbiome. It’s not yet known exactly which probiotic might work best to preventdiarrhea after a course of antibiotics.
Preventing Clostridium difficile (C. diff) Infections
C. diffis a type of bacteria that can infect the digestive system and cause severe diarrhea and other complications. There has been some study into using probiotics to prevent these infections, but there is little information on which strains of bacteria would work best against it.It’s recommended that probiotics only be used in clinical trials foractiveC. diffinfections.
After Helicobacter pylori (H. pylori) Treatment
H. pyloriis a bacterium that can cause aninfection in the stomach. Treatment includes antibiotics and other medications. Probiotics are being studied in preventing symptoms that may happen afterH. pyloritreatment. It’s not yet known which types of probiotics and in what dosage and combination might work best.
Preventing Necrotizing Enterocolitis
Babies bornprematurelycan developnecrotizing enterocolitisin their digestive system, which can be life-threatening. Probiotics are being studied to help prevent this condition. Because preterm infants are so fragile, a major concern is in the reliability and purity of probiotics on the market for this age group.
The American Gastroenterological Association (AGA) recommends certain probiotics that can be used in babies born before 37 weeks or in low birth weight babies (those weighing less than 5 pounds, 5 ounces).
Preventing Infections After Surgery
The microflora is the bacteria on the skin. Infections can develop at incision sites or elsewhere in the body after surgery. Probiotics may be used to try to prevent infections, but there’s not much evidence for their use.
Traveler’s Diarrhea
An infection causing diarrhea that occurs after consuming contaminated food or drink is referred to as traveler’s diarrhea. Preventing this infection with probiotics has been the subject of a few studies. There is some evidence that a probiotic yeast,Saccharomyces boulardii, may help prevent traveler’s diarrhea, but it is not yet settled science.
Diarrhea in Children
The AGA recommends that probiotics not be used for diarrhea from gastroenteritis (“stomach flu") in children.
Inflammatory Bowel Disease (IBD)
The studies on probiotics to treat the two main forms of IBD (Crohn’s disease and ulcerative colitis) have found no benefit. The AGA does not recommend probiotic use in people with IBD.
Irritable Bowel Syndrome (IBS)
Results of clinical trials on how probiotics may help with the symptoms of IBS have been mixed. Some show benefit, while others show no improvement. For that reason, probiotics aren’t currently recommended for IBS.
Testosterone Levels
It’s thought that some inflammatory conditions or other diseases and conditions can lead to reduced levels of testosterone (a sex hormone mainly made in the testicles). Most of the studies so far have been in mice, but at least one study showed that there may be a connection between the gut microbiome, the use of probiotics, and maintaining testosterone levels.There is no guidance on how to use probiotics for testosterone levels.
Vaginal Health
The vagina contains microorganisms that can become out of balance. This could lead to infections, such asbacterial vaginosis.There is no guidance on who might benefit from vaginal probiotics. One 2020 study has shown thatLactobacillus rhamnosusGR-1 andLactobacillus reuteriRC-14 may help prevent or treat some cases of bacterial vaginosis.
Prebiotics vs. Probiotics
It is generally thought in order to have an effect, probiotics should be taken at any time of day as long as they are taken daily for a certain period of time. The label on the probiotic supplement should give instructions on when and how to take it.
Probiotic Supplements
At least one study found that taking probiotics 30 minutes before a meal may help the live strains survive better in the digestive system. However, there have been other studies showing that taking probiotics with a meal or at a certain time of day do not have an effect.
One small 2017 study from Italy explored whether the time of day a probiotic is taken matters. The two strains studied wereBifidobacterium longumandLactobacillus rhamnosus. One group of study participants took the supplement before breakfast and another group took it after breakfast. The strains showed up in the same amounts in both groups. This discounts the importance of the time of day that taking a probiotic is most effective.
Probiotic supplements are usually only taken for a specific amount of time—usually days or, at most, weeks. There isn’t any evidence that they are any more helpful if taken every day for long periods of time. They can be expensive, so it’s important to get advice from a healthcare provider on how long to take them.
Probiotic Foods
Probiotics are found in some foods, particularlyfermented foods, which include:
Some foods may have probiotics added to them. It is difficult to know the actual probiotic content of a food because the microorganisms are living, and some may die between the production of the food and when it is eaten.
In general, kefir and yogurt are the foods that have the highest amount of probiotic organisms in them. It’s important to look for the words “live cultures” on the label so that it’s clear the food contains microorganisms.
Considerations for Those With Celiac DiseaseFor people who live withceliac diseaseand must avoid gluten, probiotic choices can be tricky. One study showed that many probiotic supplements may contain gluten.
Considerations for Those With Celiac Disease
For people who live withceliac diseaseand must avoid gluten, probiotic choices can be tricky. One study showed that many probiotic supplements may contain gluten.
Possible Side Effects From Probiotics
Probiotics are generally considered safe in people who are in good health. However, adverse effects from probiotics are possible. In addition, probiotics may not be safe for people who live with serious health conditions.
Probiotic use may be risky in infants, especially those born prematurely or with serious health conditions. People who are critically ill, immunocompromised, or those who have cancer may be at risk for harmful effects from probiotics.
Potential adverse effects of probiotics on the digestive system include:
Rashes and acne have also been reported. In some people, these effects may lessen or go away if the probiotics are taken regularly.
Managing Side Effects
Popular Forms of Probiotic Supplements
Probiotics come in many forms. Those taken orally include chewable tablets, freeze-dried capsules, powders, or liquids. They may be found in drug, vitamin, and health food stores as a supplement but might also be included in foods.
Probiotic supplements may contain more than one strain of microorganisms. For most people, the list of bacterial strains on the label will not have much meaning.
For this reason, the World Gastroenterology Organisation recommends that healthcare providers give people clear instructions on choosing a probiotic. The probiotic recommended should be based on evidence that it may be helpful for a particular condition.Trying a probiotic that hasn’t been shown to have an effect may not be useful.
Some of the common bacterial strains in probiotics include species of:
Some of the common types of yeasts that are in probiotics are:
Non-yeast fungi can also be considered probiotics, and common types include:
Colony Forming UnitsThe label for a probiotic supplement should contain the number of colony forming units (CFU) in the product. A higher number does not always mean that the product is “better” or more effective.What is important is the CFU when the product is used, because it is the “live” microorganisms that convey the health benefits. When products expire, according to the date on the label, they may not have as many live CFUs.
Colony Forming Units
The label for a probiotic supplement should contain the number of colony forming units (CFU) in the product. A higher number does not always mean that the product is “better” or more effective.What is important is the CFU when the product is used, because it is the “live” microorganisms that convey the health benefits. When products expire, according to the date on the label, they may not have as many live CFUs.
The label for a probiotic supplement should contain the number of colony forming units (CFU) in the product. A higher number does not always mean that the product is “better” or more effective.
What is important is the CFU when the product is used, because it is the “live” microorganisms that convey the health benefits. When products expire, according to the date on the label, they may not have as many live CFUs.
Summary
Probiotics are a multibillion dollar industry, yet there is still a need for quality evidence on their use. Probiotic supplements may be helpful for some diseases and conditions. People will need guidance from healthcare providers on which strains or formulations to use.
Instructions on taking a probiotic, including what time of day, with a meal or between meals, and for how many days, should be included on the supplement label.
15 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
National Institute of Environmental Health Services.Microbiome.
Sniffen JC, McFarland LV, Evans CT, Goldstein EJC.Choosing an appropriate probiotic product for your patient: an evidence-based practical guide.PLoS One.2018;13:e0209205. doi:10.1371/journal.pone.0209205
Su GL, Ko CW, Bercik P, et al.AGA clinical practice guidelines on the role of probiotics in the management of gastrointestinal disorders.Gastroenterology. 2020;159:697-705. doi:10.1053/j.gastro.2020.05.059
Ji J, Yang H.Using probiotics as supplementation forHelicobacter pyloriantibiotic therapy.Int J Mol Sci. 2020;21:1136. doi:10.3390/ijms21031136
Murphy K, Ross RP, Ryan CA, Dempsey EM, Stanton C.Probiotics, prebiotics, and synbiotics for the prevention of necrotizing enterocolitis.Front Nutr.2021;8:667188. doi:10.3389/fnut.2021.667188
Tremellen K, McPhee N, Pearce K, Benson S, Schedlowski M, Engler H.Endotoxin-initiated inflammation reduces testosterone production in men of reproductive age.Am J Physiol Endocrinol Metab.2018;314:E206-E213. doi:10.1152/ajpendo.00279.2017
Chee WJY, Chew SY, Than LTL.Vaginal microbiota and the potential of Lactobacillus derivatives in maintaining vaginal health.Microb Cell Fact.2020;19:203. doi:10.1186/s12934-020-01464-4
Hasain Z, Che Roos NA, Rahmat F, et al.Diet and pre-intervention washout modifies the effects of probiotics on gestational diabetes mellitus: a comprehensive systematic review and meta-analysis of randomized controlled trials.Nutrients. 2021;13:3045. doi:10.3390/nu13093045
Toscano M, De Grandi R, Stronati L, De Vecchi E, Drago L.Effect ofLactobacillus rhamnosusHN001 andBifidobacterium longumBB536 on the healthy gut microbiota composition at phyla and species level: a preliminary study.World J Gastroenterol.2017;23:2696-2704. doi:10.3748/wjg.v23.i15.2696
Hogan DE, Ivanina EA, Robbins DH.Probiotics: a review for clinical use.Gastroenterology & Endoscopy News. 2018:1-7.
Sotoudegan F, Daniali M, Hassani S, Nikfar S, Abdollahi M.Reappraisal of probiotics' safety in human.Food Chem Toxicol. 2019;129:22-29. doi:10.1016/j.fct.2019.04.032
World Gastroenterology Organisation Global Guidelines.Probiotics and prebiotics.
Yoha KS, Nida S, Dutta S, Moses JA, Anandharamakrishnan C.Targeted delivery of probiotics: Perspectives on research and commercialization.Probiotics Antimicrob Proteins.2022;14:15-48. doi:10.1007/s12602-021-09791-7
Aragón-Rojas S, Hernández-Álvarez AJ, Mainville I, et al.Effect of the carrier material, drying technology and dissolution media on the viability of Lactobacillus fermentum K73 during simulated gastrointestinal transit.Food Funct. 2020;11:2339–2348. doi: 10.1039/c9fo01091b.Hill C, Guarner F, Reid G, et al.Expert consensus document. The International Scientific Association for Probiotics and Prebiotics consensus statement on the scope and appropriate use of the term probiotic.Nat Rev Gastroenterol Hepatol. 2014;11:506-514. doi:10.1038/nrgastro.2014.66.
Aragón-Rojas S, Hernández-Álvarez AJ, Mainville I, et al.Effect of the carrier material, drying technology and dissolution media on the viability of Lactobacillus fermentum K73 during simulated gastrointestinal transit.Food Funct. 2020;11:2339–2348. doi: 10.1039/c9fo01091b.
Hill C, Guarner F, Reid G, et al.Expert consensus document. The International Scientific Association for Probiotics and Prebiotics consensus statement on the scope and appropriate use of the term probiotic.Nat Rev Gastroenterol Hepatol. 2014;11:506-514. doi:10.1038/nrgastro.2014.66.
Meet Our Medical Expert Board
Share Feedback
Was this page helpful?Thanks for your feedback!What is your feedback?OtherHelpfulReport an ErrorSubmit
Was this page helpful?
Thanks for your feedback!
What is your feedback?OtherHelpfulReport an ErrorSubmit
What is your feedback?
