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.

Lebwohl says IBS isn’t just about intestinal distress. For many IBS sufferers, it’s about the way our brain receives messages about pain. He describes the human colon as “almost reptilian” in the way that it contracts and relaxes throughout the day, but says these contractions are usually happening way below our threshold of consciousness, so we don’t even notice. In people with IBS, the neurotransmitters in our gut (yes, we have them in there too) may be sending severe distress signals to the brain about benign contractions happening in digestive tract.
However, a 2003 pilot study and 2011 randomized, controlled trial both reported that RA activities remained unchanged, but the subjects treated with probiotics reported statistically significantly higher levels of “subjective well-being.” One suggested reason for this was that the trials were too short to establish changes in the observable changes in the internal earmarks of RA.
Other foods without substantial research: miso (fermented soybean paste); tempeh; sauerkraut; aged soft cheese; sourdough bread; sour pickles; gundruk (nonsalted, fermented, and acidic vegetable product); sinki (indigenous fermented radish tap root food); khalpi (fermented cucumber); inziangsang (traditional fermented leafy vegetable product prepared from mustard leaves); soidonis (widespread fermented product prepared from the tip of mature bamboo shoots)
Yes. Probiotics are incredibly important and effective. We know there are more bacteria in us and on us than our own human cells. The body is almost like a puppet—it is bacteria that really runs the show: They turn on enzymes, turn off genes, and dictate much of our health. We need them to break down nutrients, like copper and magnesium, so we can better absorb them. Interestingly, studies show that conditions like anxiety, depression, and weight gain can be transferred via fecal transplants (with mice), suggesting the broad impact bacteria has on health.
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Bottom line: Probiotics are a promising field of research and may one day be used to treat or help prevent many disorders. But there’s not enough solid evidence to recommend their widespread use. Vague claims that probiotics "support good digestive health" are meaningless. Larger, longer and better studies are needed to test specific strains for specific conditions and to determine the proper doses and regimens.

There is one Voluntary Certification Program by which a supplement manufacturer can choose to be evaluated. ConsumerLab.com (CL) is the leading provider of independent test results and information to help consumers and health-care professionals identify the best quality health and nutrition products. Products that have passed their testing for identity, strength, purity, and disintegration can print the CL Seal of Approval on their product. This is one step toward being confident that one is getting the amount and type of probiotic promised by the manufacturer.


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.

Similar to yogurt, this fermented dairy product is a unique combination of milk and fermented kefir grains. Kefir has been consumed for well over 3,000 years, and the term kefir was started in Russia and Turkey and means “feeling good.” It is created by the fermentation of milk by the bacteria, and yeasts in kefir starter break down lactose in the milk — that’s why kefir may be suitable for those who are otherwise lactose-intolerant.
Evidence from clinical trials is mixed and often of low quality, but findings from meta-analyses suggest that probiotics can provide benefits in the treatment of some conditions, such as infectious and antibiotic-associated diarrhoea. As such, taking probiotics after antibiotic treatment is an increasingly common practice. However, two studies recently reported in Cell question whether taking highly concentrated supplements of so-called good bacteria aids the recovery of normal gut flora.
As the best-selling author of Happy Gut and a medical doctor who specializes in gut health and once suffered from IBS (irritable bowel syndrome), I have experienced for myself, as well as see on a daily basis, how a disrupted gut flora opens the door for unfriendly microbes to step in and take over, creating all sorts of pandemonium that causes patients to gain weight, feel sick and tired, and become more disease-prone.
Until recently, testing of probiotics by ConsumerLab.com found that some products had far lower amounts of live organisms than claimed on the labels. But in 2018, it found that 17 out of 18 products tested contained the amounts listed; none exceeded limits for heavy metal contaminants. In contrast, in 2016, a study in Pediatric Research found that only one out of 16 Bifidobacterium longum supplements tested contained the species named on the label.
If that's not enough, your doctor may also suggest a probiotic supplement. But don't go and grab just anything off the pharmacy shelf. Probiotic supplements are not all the same, and they often contain different strains to serve different needs, says naturopathic physician Amy Fasig. Example: What one person gets to battle strep throat is different from what would be prescribed for someone suffering from Irritable Bowel Syndrome, she says.
Also, it’s important to understand that probiotics are not a new idea. Throughout history, cultures have thrived on probiotics found in fermented foods and cultured foods, which were invented for food preservation long before the refrigerator. The process of fermentation has been lost in recent years, as it is no longer needed to preserve foods, meaning that we now lose out on those vital probiotics benefits.
If you decide to use a probiotic supplement and get clearance from your doctor for doing so, be sure to read the label carefully. You want to be sure that the supplement contains live strains of the bacteria or yeast, and that the life of these strains is guaranteed at the time of use, and not at the time of manufacture. Other points of comparison are the number of bacteria strains and the number of colony-forming units, although this does not necessarily guarantee results.
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.”

Overall, Enzymatic Therapy Acidophilus Pearls are a great daily probiotic supplement. They give you a ton of flexibility and is convenient since it doesn’t need to be refrigerated and can be taken with or without food! This probiotic makes on-the-go belly support a breeze. All in all, Enzymatic Therapy Acidophilus Pearls finally make it easy to travel with probiotics, are simple to take, and can give you the piece of mind that the money you’re spending on probiotics isn’t being wasted at the first sign of stomach acid.  Read the full review here… or click here to go buy it now!
B. Longum is one of the first types of bacteria to colonize our bodies at birth. These important microorganisms ferment sugars into lactic acid, helping to stabilize the acidity of the GI tract and inhibit growth of harmful bacteria. For a group of adults prone to constipation, taking a mix of B. Longum BB536 with milk or yogurt for 2 weeks increased bowel movements [1].
Two large-scale clinical trials recently reported in the New England Journal of Medicine suggest that the situation in infectious diarrhoea might also be more complex than previously believed. Freedman and colleagues did a randomised controlled trial of a probiotic containing Lactobacillus rhamnosus and Lactobacillus helveticus in children presenting to the emergency department with gastroenteritis. Contrary to expectations, they found that the probiotic did not prevent development of moderate-to-severe gastroenteritis within 14 days after enrolment. In a separate study, Schnadower and colleagues found similar results with L rhamnosus GG alone. Both trials used probiotics that are available over the counter in North America and showed no significant difference from placebo in the duration of diarrhoea and vomiting, number of unscheduled health-care visits, or length of absence from day care. These results cannot be generalised to other probiotic strains or preparations, but they do show that we have some way to go in elucidating which probiotics might provide benefits in which clinical settings.
In a separate study involving 21 healthy volunteers, also published today in Cell, the same group of researchers found that taking probiotics after treatment with broad spectrum antibiotics may actually delay the return of people's normal gut microbiome. This goes against the idea that probiotics can help "repopulate" people's gut bacteria after antibiotics wipe them out.
In October 2013, the International Scientific Association for Probiotics and Prebiotics (ISAPP) organized a meeting of clinical and scientific experts on probiotics (with specialties in gastroenterology, pediatrics, family medicine, gut microbiota, microbiology of probiotic bacteria, microbial genetics, immunology, and food science) to reexamine the concept of probiotics. They define probiotics as "live microorganisms that, when administered in adequate amounts, confer a health benefit on the host." They also differentiated between products containing probiotics and those containing live or active cultures and established the following criteria:
​​​​​​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.*
★100% NATURAL, NON-GMO, GLUTEN FREE★NewRhythm 50 Billion Probiotics is Formulated with 100% Natural Ingredients and Independently Tested in 3rd Party Labs in USA. Our Turmeric Supplement is Verified NON-GMO, Gluten Free and Verified Free of Sugar, Soy, Yeast, Egg, Wheat, Corn, Peanuts, Fish, Shellfish, Magnesium Stearate, Artificial Ingredients, Fillers, Binders, Preservatives.
Many Lactobacillus and Bifidobacterium species are naturals at protecting and improving gut health. Additionally, research in animals and humans has shown that probiotics decrease scores on depression assessments, thereby alleviating depression. As a matter of fact, there is a new term, psychobiotics, for these microbes that influence mental health conditions like depression.
Walk into any grocery store, and you will likely find more than a few “probiotic” products brimming with so-called beneficial bacteria that are supposed to treat everything from constipation to obesity to depression. In addition to foods traditionally prepared with live bacterial cultures (such as yogurt and other fermented dairy products), consumers can now purchase probiotic capsules and pills, fruit juices, cereals, sausages, cookies, candy, granola bars and pet food. Indeed, the popularity of probiotics has grown so much in recent years that manufacturers have even added the microorganisms to cosmetics and mattresses.

After the antibiotics had cleared the way, the standard probiotics could easily colonize the gut of everyone in the second group, but to the team's surprise, this probiotic colonization prevented the host's normal microbiome and gut gene expression profile from returning to their normal state for months afterward. In contrast, the aFMT resulted in the third group's native gut microbiome and gene program returning to normal within days.

For the generally healthy person, you can make a very good case to trust your own body to select and grow the best bacteria that are already in everyone. The foods you eat greatly influence your bacterial mix. Although probiotics offer many positive health benefits, there is no guarantee that they can make the trip from your mouth to your lower gut intact. Although adding more prebiotic fiber to your diet cannot guarantee safe passage of probiotics, it can influence the healthy bacteria that already live in your system. If probiotics help you, eating prebiotic foods or supplements will cause those healthy bacteria to flourish.

Best Probiotic says that Suprema Dophilus, manufactured and distributed by Vitabase, enjoys the highest customer rating in the market. Specially coated to help the bacteria spread through your entire digestive tract, its website claims over four billion viable cells per capsule, including five lactobacillus strains and three bifidobacteria cultures. Best Probiotic says that Suprema Dophilus also contains fructo-oligosaccarides to increase the life span of the bacteria.
However, these quality of life improvements are varied, and some improvements are quite mild. Sample group, types of allergies, symptoms, and results are across a broad spectrum. For example, numerous studies have shown that allergic rhinitis responses to the household dust mite decrease significantly in adults and children when probiotics were used. However, people allergic to birch pollen saw neither a decrease in general allergic responses to birch pollen or to apple food.
Update: I think this product is being smeared by a competitor! Look at all the reviews in April. Suddenly, a butt ton of not just negative but 1 star reviews. It's uncanny. So, what would compel a competitor to do such a thing? Well, it was the only 50 CFU, enteric coated & 20 strain probiotic on Amazon & it cost about 15 bucks. That, while products far inferior to it were priced for - often times - 2 or 3x as much.
Evidence from clinical trials is mixed and often of low quality, but findings from meta-analyses suggest that probiotics can provide benefits in the treatment of some conditions, such as infectious and antibiotic-associated diarrhoea. As such, taking probiotics after antibiotic treatment is an increasingly common practice. However, two studies recently reported in Cell question whether taking highly concentrated supplements of so-called good bacteria aids the recovery of normal gut flora.
The label should also specify that the living microbes are viable through end of shelf life or best by date rather than at time of manufacture to ensure the bacteria are still live when you take them and able to reach your colon. Quality trumps everything- supplements that are a bargain are typically not of quality. A good probiotic (depending on strands) can cost anywhere from $25-$60.
Update: I think this product is being smeared by a competitor! Look at all the reviews in April. Suddenly, a butt ton of not just negative but 1 star reviews. It's uncanny. So, what would compel a competitor to do such a thing? Well, it was the only 50 CFU, enteric coated & 20 strain probiotic on Amazon & it cost about 15 bucks. That, while products far inferior to it were priced for - often times - 2 or 3x as much.
The views expressed in this article intend to highlight alternative studies and induce conversation. They are the views of the author and do not necessarily represent the views of goop, and are for informational purposes only, even if and to the extent that this article features the advice of physicians and medical practitioners. This article is not, nor is it intended to be, a substitute for professional medical advice, diagnosis, or treatment, and should never be relied upon for specific medical advice.
​​​​​​AZO Complete Feminine BalanceTM is a daily probiotic supplement designed for the unique needs of women. Researchers that formulated the blend started by selecting species that are dominant in the healthy vaginal microbiota. Then they further refined the formula by selecting strains of probiotics that flourish in the vagina. The blend is clinically proven to help protect vaginal/feminine health.*
The other thing to remember is that these microorganisms are not all created equally. In fact, the genus, strain, and species all need to be the same for the results that found in the study to be the results that one hopes to achieve when taking it. For example, with the strain Lactobacillus rhamnosus GG, the genus is Lactobacillus, the species is rhamnosus, and the strain is GG. If any one of those is different in your supplement, you may not attain the same results.
Because there's a huge variety of probiotic products available on the market, many people struggle to find the right one for them. "There are many different strains of bacteria in different combinations within different probiotic supplements," explains Brooke Scheller, a clinical and functional nutritionist. "For example, a probiotic may contain a single strain of bacteria or many. It may also contain other vitamins, minerals, or other ingredients that may tout health benefits," she says. There are many different dosages, delivery systems (powder, tablets, capsules), and formulations (refrigerated vs. shelf-stable), and some probiotics also contain prebiotics, which basically act as fertilizer for the probiotics. (Related: Why Your Probiotic Needs a Prebiotic Partner)

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.
Have you ever baked bread and had to proof the yeast? Proofing the yeast allows it to become active in the conditions it prefers the most: warm and moist with access to sugar. Baker’s and brewer’s yeast are both forms of Saccharomyces yeasts, as is Saccharomyces boulardii, but these yeasts are usually helpful to you and noninfectious, except in immunocompromised people or people with yeast allergies.

Niv Zmora, Gili Zilberman-Schapira, Jotham Suez, Uria Mor, Mally Dori-Bachash, Stavros Bashiardes, Eran Kotler, Maya Zur, Dana Regev-Lehavi, Rotem Ben-Zeev Brik, Sara Federici, Yotam Cohen, Raquel Linevsky, Daphna Rothschild, Andreas E. Moor, Shani Ben-Moshe, Alon Harmelin, Shalev Itzkovitz, Nitsan Maharshak, Oren Shibolet, Hagit Shapiro, Meirav Pevsner-Fischer, Itai Sharon, Zamir Halpern, Eran Segal, Eran Elinav. Personalized Gut Mucosal Colonization Resistance to Empiric Probiotics Is Associated with Unique Host and Microbiome Features. Cell, 2018; 174 (6): 1388 DOI: 10.1016/j.cell.2018.08.041

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