Myriad factors – antibiotics, diet, stress, and age, among them – affect the balance of diverse microbes present in your gut. While you can replenish your gut bacteria by eating well and incorporating natural probiotics (ex. yogurt and kefir) into a healthy diet, these processes can take weeks or months; taking a regular probiotic is an easy and effective way to ensure your gut (and immune system) stays healthy, always.
The takeaway: Certain strains were found useful in preventing diarrhea among children being prescribed antibiotics. A 2013 review showed that after antibiotic use, probiotics help prevent Clostridium difficile-associated diarrhea. A review focused on acute infectious diarrhea found a benefit, again for certain strains of bacteria at controlled doses. There’s also evidence that they may help prevent necrotizing enterocolitis (a serious gastrointestinal condition) and death in preterm infants.
Notions don’t equal evidence though, and Lebwohl cautioned against thinking of probiotics as a cure-all, and examining the ways in which they’ve been proven to work as well as the ways in which they really haven’t. So which medical conditions have probiotics actually shown promise in treating and which claims have the credibility of a used car salesman on acid?
To boost the immune system, B. Lactis is a promising choice. One study had participants taking either a probiotic or a placebo for 6 weeks. At the end of the period, researchers measured antibody levels and found greater increases in antibodies of the B. Lactis group than in placebo participants, concluding that this probiotic may help improve immune function [1]. In addition, a 2009 study found that supplementation of the strain B. Lactis DN-173 led to self-reported improvements in digestive comfort [2].

While this feature contributes to the efficiency of the product, it is unclear whether this product is vegetarian like some of the other probiotics we reviewed. Therefore, if you have any dietary restrictions or needs, this may not be the best probiotic for you and may, in fact, cause additional stomach upset or irritation. It is however gluten-free.
More than 80 years later, probiotics have become wildly popular and incredibly profitable. A 2012 survey by the National Institutes of Health showed that 3.9 million Americans stated they had used some form of probiotics or prebiotics (a type of dietary fiber thought to feed the friendly bacteria in your gut) in the last 30 days—3 million more people than in the previous study in 2007. Probiotics are now available for consumption in almost every imaginable form—pills, tablets, yogurts, juices, cereals, and energy bars. They have been touted as having benefits not only for digestive health, but also mood disorders, cancer, cold and flu prevention, and reproductive health issues.
Although people often think of bacteria and other microorganisms as harmful “germs,” many microorganisms help our bodies function properly. For example, bacteria that are normally present in our intestines help digest food, destroy disease-causing microorganisms, and produce vitamins. Large numbers of microorganisms live on and in our bodies. Many of the microorganisms in probiotic products are the same as or similar to microorganisms that naturally live in our bodies.

Overall, Align Probiotic is one of the better “daily” probiotics out there.  It’s easy to take, comes in convenient packaging and doesn’t require refrigeration.  And it has some research showing it helps with gas, bloating and constipation, especially in women with IBS.  Lots of things to like about this probiotic!  Read the full review here… or click here to go buy it now!
Previous studies have been contradictory, with some yielding more positive results about the benefits of probiotics, but most of them looked at probiotics in stool samples, not directly in the gut itself. In the new research, the scientists used more invasive methods to take samples of gut bacteria directly from different areas of the digestive system.

Nearly 75% of all women will have at least one yeast infection during their lifetime, and over 50% of women are likely to experience the inexplicable pain of a urinary tract infection as well. With the recurrence of urinary tract infections and yeast infections on the rise, women all around the world began searching for a more effective and natural solution to antibiotics.
Taking relatively high doses of these probiotic strains before, during, and after antibiotic treatment can help your microbiome get back on its feet: B. Lactis, B. Infantis, L. Acidophilus, L. Casei, L. Bulgaricus, L. Paracasei, L. Rhamnosus GG, and S. Boulardii. Our antibiotic combatant MegaFood MegaFlora has six of these strains, as well as eight others. One serving contains 20 billion CFUs to replenish the good bacteria.

Probiotics have become buzzy in recent years: Celebrities including Lauren Conrad and Anna Paquin have been spotted carrying bottles of kombucha, a probiotic-containing fermented tea, and the probiotics market has been growing rapidly as more people pursue better health by taking probiotic supplements. Prebiotics are attracting notice too, but you may still be unsure of what exactly prebiotics and probiotics are. Here's what you need to know about them to decide whether taking supplements is right for you.
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Cynthia is the assistant editor and frequent contributor. She’s originally from California, but has lived in many countries including South Korea, China and Germany. She currently lives with her husband in Minnesota. Cynthia is passionate about helping families find the best advice for family life and safety. Cynthia also has experience in early childhood education and holds a TEFL-C certificate from Teachers College, Columbia University. She has been writing about family-focused topics, advice and trends since 2014.

While past studies have investigated similar questions, they have all used patients' excrement as a proxy for microbe activity in the GI tract. Instead, Elinav, his colleague Eran Segal, (a computational biologist at the Weizmann Institute), and their teams spearheaded by Niv Zmora, Jotham Suez, Gili Zilberman Schapira, and Uria Mor of the Elinav lab collaborated with Zamir Halpern, Chief of Gastroenterology at the Tel Aviv Medical Center to measure gut colonization directly.
You may have heard some questions over whether SBOs are safe: The NIH has a presumed case report, which hasn’t been 100 percent verified, of someone with Lymphoma getting septicemia from taking a SBO (the organism B. subtilis). Some say that if you have leaky gut, you should heal it before supplementing with SBOs. If you are immunocompromised or have cancer, you can consult with a physician first to be safe.

Nearly 75% of all women will have at least one yeast infection during their lifetime, and over 50% of women are likely to experience the inexplicable pain of a urinary tract infection as well. With the recurrence of urinary tract infections and yeast infections on the rise, women all around the world began searching for a more effective and natural solution to antibiotics.


It is well known that people with lactose intolerance can often consume yogurt with few symptoms. This is because the probiotics in yogurt help digest the lactose in the small intestine, before it reaches the colon. In addition, the yogurt starter cultures L. bulgaricus and Streptococcus thermophilus help to break down the lactose. Because of its probiotics, yogurt is a good way for people with lactose intolerance to consume the recommended servings of dairy without experiencing uncomfortable symptoms they may get from other dairy products.
Unlike MegaFood, the Renew Life label’s cold-storage recommendation is printed so small we nearly missed it (and it didn’t ship with a cold pack). If a probiotic requires refrigeration, be vigilant when buying it — the retailer that stores it or the company that ships it should keep it refrigerated until it gets to you. Otherwise, some of its potency might diminish in storage or transit.
You also want to look at the guarantee fine print: If the CFU number is guaranteed at time of manufacturing, but not at the time of expiration, you could be taking a less potent dose of probiotics than you think because potency fades over time. I made this mistake when I was traveling once and went to the grocery store to pick up probiotics. On the bottle label it said guaranteed at 20 billion CFU at the time of manufacturing. This doesn’t tell you the CFU for when I was actually taking the probiotics. For instance, our probiotics are manufactured at 60 billion and 200 billion CFU, and guaranteed at 30 billion and 100 billion CFU, respectively, at time of expiration.
Many women are prone to yeast infections during or after antibiotic use. If you are one of these unlucky few, try taking a probiotic like the vH Probiotics with Prebiotics and Cranberry immediately before taking your antibiotics. (You may want to check with your doctor first though). These cultures may help with stomach upset and can also prevent a dreaded yeast infection!
More than 80 years later, probiotics have become wildly popular and incredibly profitable. A 2012 survey by the National Institutes of Health showed that 3.9 million Americans stated they had used some form of probiotics or prebiotics (a type of dietary fiber thought to feed the friendly bacteria in your gut) in the last 30 days—3 million more people than in the previous study in 2007. Probiotics are now available for consumption in almost every imaginable form—pills, tablets, yogurts, juices, cereals, and energy bars. They have been touted as having benefits not only for digestive health, but also mood disorders, cancer, cold and flu prevention, and reproductive health issues.
Using probiotics benefits and balances immune function, influences hormone levels, aids in digestion and nutrient absorption, produces some vitamins, and balances blood sugar insulin responses. By preventing and reducing leaky gut and controlling levels of pathogens, probiotics reduce harmful bacterial by-products that can enter the brain and contribute to brain fog.

"The proprietary formula in this lotion supports a healthy microbiome of your skin promoting a more hydrated, stronger barrier function and protection from pathogens without harming the good stuff. Throw away your antibacterial soap and hand sanitizer and use this all over after your shower and after washing your hands," says Astarita, who is also a fan of the Nerium Prolistic Powder Pre & Probiotic Plus Vitamins ($45) and Be Well Probiotic Powder ($46) by Dr. Frank Lipman.

DNA Shift is a once-daily, powerful probiotic delivering 50 billion CFUs and 11 probiotic strains. It’s perfect for both men and women who want to improve their gut and brain health. With long-term use, you may even see improved mood and energy levels. This probiotic can help relieve the following: symptoms of gas and bloating, constipation indigestion, irregularity, leaky gut, and diarrhea induced by antibiotics.


Do you strain with infrequent bowel movements? Do the feces look like separate hard lumps or like bunches of hard lumps stuck together, or are they pencil-thin? You may have constipation. The Bristol stool chart (BSC) was developed by two doctors as a way to differentiate between states of constipation, normal elimination, a state of lacking fiber, and states of inflammation. Stools are supposed to be long and sausage-like, with few or no cracks in the surface.
A slightly more surprising result, however, seems to be the way that probiotics may impact some of the symptoms of autism. Autism and gut health have been discussed for some time, as patients with the disorder typically suffer from a large number of digestive issues. However, based on animal studies, it seems possible that altering the quality of gut bacteria might benefit not only the digestive system, but the abnormal behaviors in autism, too. In 2016, a case study of a boy with severe autism was reported. While being treated with probiotics for digestive problems, the patient spontaneously improved on the ADOS scale, a diagnostic rating system for people with autism. The score dropped from 20 down three points to a stable 17, and according to the report, ADOS scores do not “fluctuate spontaneously along time” and are “absolutely stable.”
Candida albicans is the most common species that causes yeast infections, but there are others. It is a normal inhabitant of the gastrointestinal tract and is often found in the female vaginal tract. Candida infections on the skin cause red, itchy rashes that often weep moisture, and in the vagina there is often a cottage-cheese-like discharge in addition to the skin symptoms.
A diet high in vegetables, fruit, and fiber, along with probiotics for weight loss, supports a more diverse gut microbiome, which in turn helps weight loss. Instead of waiting for the next magical diet or weight-loss supplement to arrive, focus on improving your gut health with probiotic foods and drinks with live cultures, in addition to maintaining healthy lifestyle factors.
​​​​​​Lactobacilli dominate a healthy vaginal microbiota. Menstrual cycles, sexual activity, diet, certain medications, hygiene, and other factors can occasionally disrupt the vaginal microbiome. AZO Feminine Balance Daily Probiotic has been clinically demonstrated to contribute to the colonization of these important lactobacilli in the vagina.* The result: restoring the natural balance of good bacteria and yeast to maintain vaginal health.*
Given that you can get probiotics from the food you eat, you don't necessarily need to take a supplement, and Keatley says she prefers food sources of probiotics to supplements. However, she adds that "There are times when you really need a boost." One example might be during or after a course of antibiotics, as long as you have your doctor's OK, since antibiotics kill both good and bad bacteria: "Seeding your gut with good bacteria can lay the groundwork for a faster recovery and less constipation and diarrhea," Keatley points out. Angelone echoes Keatley's emphasis on food sources of probiotics, but also says that supplements can also play a useful role in "maintaining a healthy gut bacteria colony."
Given that you can get probiotics from the food you eat, you don't necessarily need to take a supplement, and Keatley says she prefers food sources of probiotics to supplements. However, she adds that "There are times when you really need a boost." One example might be during or after a course of antibiotics, as long as you have your doctor's OK, since antibiotics kill both good and bad bacteria: "Seeding your gut with good bacteria can lay the groundwork for a faster recovery and less constipation and diarrhea," Keatley points out. Angelone echoes Keatley's emphasis on food sources of probiotics, but also says that supplements can also play a useful role in "maintaining a healthy gut bacteria colony."

They probably are. Lebwohl says probiotics may decrease the risk of getting diarrhea during the course of taking antibiotics, and may also play a role in specifically preventing the development of the dreaded antibiotic-related super diarrhea called C. difficile or C. diff. Antibiotics can wipe out the good bacteria that keep you from getting sick if you’re exposed to C. diff, or if you already have it in your system. C. diff symptoms can range from a moderate watery diarrhea several times a day to severe infections, which can be accompanied by fever, bloody stools, rapid heart rate, and can even lead to kidney failure. 500,000 Americans were infected with C. diff in 2015 and 15,000 died from it.

About 60 to 80 percent of our immune system lives in our gut. Imbalances in the gut’s microbiome (which is primarily made up of bacteria) lead to digestive issues, while many many other potential effects can be felt throughout the body—from feelings of fatigue to depression, thyroid dysfunction, autoimmunity, and a host of skin issues. Conditions like rosacea, psoriasis, eczema, and acne are really inflammatory conditions, and often a manifestation of something that is happening deeper within the body. When you fix the gut (which, depending on your health, might include getting rid of an infection like Candida, eating a clean diet, and taking a probiotic), skin issues often resolve as well.
Look for the probiotic yeast Saccharomyces boulardii (S. Boulardii)—you can take it as a separate supplement or find it in multi-strain probotics. Studies show that it is effective at preventing antibiotic-induced diarrhea and Clostridium diffcicile (C. difficile) infection, which a course of antibiotics can cause. Saccharomyces boulardii increases your secretory IgA—in other words, it strengthens the immune system in the gut. (Some people say that Saccharomyces boulardii is also the panacea for Candida—it’s a yeast that fights yeast—but while it’s helpful for some, other people do not tolerate it well, so I recommend trying it as an individual supplement first to see how you respond.)

The other way that probiotics help is the impact that they have on our immune system. Some believe that this role is the most important. Our immune system is our protection against germs. When it doesn't function properly, we can suffer from allergic reactions, autoimmune disorders (for example, ulcerative colitis, Crohn's disease, and rheumatoid arthritis), and infections (for example, infectious diarrhea, H. pylori, skin infections, and vaginal infections). By maintaining the correct balance from birth, the hope would be to prevent these ailments. Our immune system can benefit anytime that balanced is restored, so it's never too late.


To factor strain-specific benefits into our efficacy score, we referenced the information in these guides. Products were rewarded for containing strains on these lists. Additionally, measured levels of each strain were compared to what is thought to be effective based on these guides, and scores were scaled accordingly. In cases where products did not list strain-specific amounts, or their listed strains were not included in these guides, total measured CFUs were compared to a general effectiveness threshold of 1 billion CFUs cited by research published in the American Journal of Clinical Nutrition11.
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