The discovery of the benefits of probiotics began with sour milk. Today we have many other options to get various bacteria from our foods, although it's not as simple as just adding them to the food. For there to be health benefits, the microorganism has to be able to survive the passage through the gastrointestinal tract, survive the food manufacturing process, and grow and survive during the ripening or storage period. Also, the bacteria must not negatively affect product quality and be included on the Generally Recognized as Safe (GRAS) list.
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.
When I polled friends and family about their personal experiences with probiotics, I got a real mixed bag of responses. Some called them a lifesaver and others felt no effects whatsoever. I put the anecdotes aside and talked to Ben Lebwohl, gastroenterologist and director of clinical research at Columbia University’s Celiac Disease Center, to get the straight poop on whether probiotics are miracle or myth.
Because of the way bacteria spread from the rectum to the vagina and urinary tract in women, probiotics have been a proposed remedy for urinary tract infection (UTI) in women. A 2012 review confirmed that probiotics seem to be effective in preventing recurrent UTIs, but more research is required before a determination can be made. The healthy strains of bacteria that help achieve this are also somewhat less common, which means proper treatment could be logistically complicated.
Some foods are made by adding bacteria — yogurt, pickles, cottage cheese, kombucha, and sauerkraut are good examples. Those foods work to provide the same probiotic benefits as supplements. However, most foods are so processed and pasteurized that it’s unlikely you’ll see the same benefits, let alone the right strains, as you would with a supplement. Regardless, it can’t hurt to get extra probiotics through your diet.
Consumer Reports is an independent, non-profit organization dedicated to helping consumers. We make it easy to buy the right product from a variety of retailers. Clicking a retailer link will take you to that retailer’s website to shop. When you shop through retailer links on our site, we may earn an affiliate commission – 100% of the fees we collect are used to support our mission. Learn more. Our service is unbiased: retailers can’t influence placement. All prices are subject to change.

Though most probiotics are formulated for both men and women, Garden of Life’s Raw Probiotics for Women is manufactured with women in mind. This probiotic has a whopping 85 billion live cultures and 32 different probiotic strains to target everything from gut and vaginal health to thyroid and nutrient absorption. It contains two popular probiotics, Lactobacillus acidophilus and Bifidobacterium, and is gluten-free, soy-free, and made without fillers or binder—which is great for anyone with dietary restrictions or allergies. Each container comes with 90 capsules; the recommended dose is three capsules per day.
Quick note about some formulations with multiple strains (including this one): Take a look at the label below and you’ll see that the supplement contains a mix of strains, but the label just says there is a total of 20 billion CFUs (how they measure the amount of bacteria). This does not tell us how much of each particular strain there is, and we want to know that there are at least 1 billion CFUs per strain to get a beneficial effect.
The National Institute of Health (NIH) is sponsoring the Human Microbiome Project (HMP), which is developing research resources to enable the study of the microbial communities that live in and on our bodies and the roles they play in human health and disease. The NIH has funded many more medical studies using HMP data and techniques, including the role of the gut microbiome in Crohn's disease, ulcerative colitis, and esophageal cancer; skin microbiome in psoriasis, atopic dermatitis, and immunodeficiency; urogenital microbiome in reproductive and sexual history and circumcision; and a number of childhood disorders, including pediatric abdominal pain, intestinal inflammation, and necrotizing enterocolitis, a severe condition in premature infants in which the intestine tissue dies due to lack of oxygen.

Suez and colleagues investigated the recovery of the gut microbiota after antibiotic treatment and found that probiotics might perturb rather than aid this process. The probiotics rapidly colonised the gut but prevented the normal microbiota from repopulating for up to 5 months. While likely to be considerably less appealing, the group who received autologous faecal microbiota transplantation recovered their microbiota the quickest, with the composition of the microbiota returning to normal within days. Furthermore, Zmora and colleagues showed that colonisation occurred in highly individualised patterns, with some people's gastrointestinal tracts rejecting probiotics and others allowing colonisation by the probiotic strain, meaning that many individuals taking probiotic supplements are simply wasting their money.
Because of the way bacteria spread from the rectum to the vagina and urinary tract in women, probiotics have been a proposed remedy for urinary tract infection (UTI) in women. A 2012 review confirmed that probiotics seem to be effective in preventing recurrent UTIs, but more research is required before a determination can be made. The healthy strains of bacteria that help achieve this are also somewhat less common, which means proper treatment could be logistically complicated.
Quality matters for any supplement, and that goes triple for probiotics. Many commercial brands lack the technology to identify specific strains and how much of that strain each dose contains. That could mean you get an ineffective or potentially harmful dose. It's a great sign if the company is using strains that have been used specifically in clinical trials at a dose similar to or the same as that used in the study. This is one of the only ways to guarantee a probiotic's clinical effectiveness.
While the logic behind probiotics might seem sound, it is clear that we have a long way to go before understanding the complexity of the microbiota and the effects—both good and bad—that probiotics might have. All individuals have a unique gut microbiome, and the effects of different bacteria on different people are likely to be highly variable; as such, probiotic use might even need to be personalised for optimal benefits. Commercially available products might not contain the correct strains or quantities of bacteria to provide benefits, and most probiotic supplements contain only single strains, vastly oversimplifying the complexity of the microbiota. While taking a supplement for improved health is certainly an attractive prospect, those looking to aid their gut microbiota might be better served by consuming a healthy, varied diet. In the meantime, rigorous clinical trials are needed to substantiate potential health benefits and to confirm whether probiotics are elixirs or just empty promises.
CFU: This is the number of "colony forming units" present in each dose, which are measured in the billions. And while more isn't always better, "you want at least 20 to 50 billion CFU," says Dr. Nazareth. Just for reference, a very high dose is 400 CFU, which most experts agree is not necessary unless your health care practitioner specifically recommends this for you. It's also important to check for the guaranteed CFU upon expiration, which should be listed clearly. "Some products only guarantee the CFU number at the time of manufacturing, therefore will be less potent by the time the product reaches your home," she says.
The vH Probiotics with Prebiotics and Cranberry are specifically designed to give you complete feminine tract care, and work to fight recurrent yeast infections and urinary symptoms. While this particular probiotic formula may provide some digestive relief, it is important to note that it is largely marketed towards women with these feminine health conditions. For that reason, women that are looking for more digestive care should consider a different probiotic that is more geared towards gut health.
The probiotic industry is booming, but the benefits of probiotic products and the quantity of viable bacteria they contain can vary. So, instead of adding bacteria from an outside source, you might be better off consuming prebiotics, like fermentable fiber, which support your own beneficial bacteria, Dr. Cresci says. Good dietary sources of prebiotics include dried beans and other legumes, garlic, asparagus, onions, leeks, certain artichokes, green bananas and wheat. Prebiotic supplements are available, as well.
Dr. Michelle Schoffro Cook says there’s no single best strain of bacteria, though some strains, like L. Acidophilus or B. Bacterium, have wide-reaching effects. They often act as a starting point from which to add other strains with more specific impacts. Already have probiotics on hand or want to arm yourself with raw knowledge before you shop? The table below shows the research- and expert-backed strains we looked for in each use case:
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!
Digestive tract conditions. Probiotic supplements may be useful in treating and preventing inflammatory conditions, such as pouchitis (which affects people who have their colons removed), inflammatory bowel diseases (such as ulcerative colitis and Crohn's disease), and chronic stomach inflammation and ulcers caused by Helicobacter pylori bacterium. They may also be helpful in treating constipation, irritable bowel syndrome, acid reflux, spastic colon; shortening the duration of infectious diarrhea; and reducing the recurrence of bladder and colorectal cancer. Some studies suggest that yogurt is helpful in preventing diarrhea - a common side effect of treatment with antibiotics. It has also been shown to prevent or treat urinary tract infections and vaginal yeast infections in women.

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.
Overall, I really like TruBiotics as a daily probiotic. First of all, the capsules are easy to take and you only need one a day. I also like the choice of strains they used in this probiotic. Overall, TruBiotics is a great daily probiotic that’s quick and convenient and may be very effective with regards to many different digestive issues.   Read the full review here… or click here to go buy it now!

Probiotic supplements and foods can play a major positive role in brain fog. Lactobacillus, in particular, can produce neurotransmitters used for brain neuron-to-neuron transmission to facilitate thinking. Probiotics can interact with the vagus nerve to the brain, with the enteric nervous system that can communicate with the brain, and with the brain via chemical messengers.
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.

Quick note about some formulations with multiple strains (including this one): Take a look at the label below and you’ll see that the supplement contains a mix of strains, but the label just says there is a total of 20 billion CFUs (how they measure the amount of bacteria). This does not tell us how much of each particular strain there is, and we want to know that there are at least 1 billion CFUs per strain to get a beneficial effect.
Known as the most clinically proven effective probiotic strain, Lactobacillus rhamnosus GG (otherwise known as “LGG”) has been clinically proven to maintain healthy numbers of bacteria and yeast for optimal digestive health. This powerful probiotic is also paired with some of the best probiotic strains for feminine health, making it an ideal choice for any woman that is looking for complete care from her probiotic. 

If you’re new to Bio-K+, know that each bottle contains 50 billion live and active probiotic bacteria. Probiotics are good for a wide variety of digestive issues, so it’s best to customize your dosage based on what your specific needs are. If you are looking to take a preventative dosage to support the health of your microbiome, start with a ¼ bottle per day. If you suffer from digestive health issues or regularly take antacids, start with a ½ bottle of Bio-K+ per day. If you have more serious gastrointestinal issues or have had to take antibiotics, Bio-K+ probiotics are great for getting your system back on track. Start with a full bottle per day and see how you feel (we’ve had amazing results from our fans!)

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:
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.
Unfortunately, many commercial brands don’t measure up. They are unstable in stomach acid. Quality control measures aren’t intact, including ensuring supplements have been handled correctly and maintain their freshness. Moisture slipping into probiotic supplements can reduce their efficacy. Companies that use bioshield capsules produce higher quality probiotic supplements that are able to endure the stomach acid, releasing their contents within the small intestine, where a more alkaline environment ensures the survival of the bacteria.
In 2019, dietary restrictions have become so mainstream that it is virtually impossible to step into a restaurant without spotting a specialized menu for dairy, gluten, vegan, and vegetarian eaters. The supplement industry is no exception and the majority of high-quality probiotics available on the market today include vegan or vegetarian capsules. Many brands are also gluten-free these days as well, and several are dedicated to keeping their formulas free of dairy, soy, and many other common allergens.
​​​​​​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.*
Probiotics One Daily Support is easily one of our favorite probiotics right now and currently sits at #2 in our ranking of the best probiotics supplements.  There’s a number of reasons why I like it so much, but the main one is I just felt SO much better while taking it!  My stomach (which sometimes gives me issues due to IBS) felt great and I had a bit more energy than usual.  I was also able to digest all my meals without any problems, a major plus!  Further, Daily Support is very allergy-friendly, doesn’t require refrigeration and comes with a 60-day guarantee.  So all-in-all, we gave Probiotics One 5 out of 5 stars and truly think it’s a REALLY great probiotic.  Read the full review here… or click here to go buy it now!

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.


Even if you’re not sensitive to dairy, though, probiotics that require refrigeration can be inconvenient; but there are now some that don’t need to be kept cold. For example, our probiotics are sealed in nitrogen blister packs to protect them from heat, as well as moisture and oxygen because the air can’t get in. Look for probiotics that are individually packed to protect the live cultures. If they just come in a bottle they could be losing potency from air getting in.
Probiotics can be found in some foods, such as yogurt and cheese, as well as dietary supplements. There are numerous probiotic supplements on the market that contain a variety of bacteria. The two most common types of bacteria found in probiotics belong to the groups known as Lactobacillus and Bifidobacterium. Phillips'® Colon Health® Probiotic Capsules contain 3 types of good bacteria, from both groups, to help defend against occasional constipation, diarrhea, gas and bloating.∗
A Seal of Approval When looking for a good probiotic, Gans advises consumers to buy from a trusted retailer and look for a seal from a third-party certifier. “Reputable probiotic supplements should list the genus, species, and strain, in addition to the number of organisms that will be alive by the use-by date and the dose on the label,” says Gans. This transparency will help consumers understand what’s in their supplement and how to best use it.
★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.
That said, you don’t have to live in pain any longer and there are products that can help ease your symptoms without an added hassle! Whether you are struggling with yeast infections, recurrent urinary tract infections, digestive symptoms, or menopause, probiotics can dramatically increase your quality of life and ease your symptoms. After all, when you’re pain-free, nothing can stand in your way! You can also view probiotics for men here.
Historically, people had plenty of probiotics in their diets from eating fresh foods from good soil and by fermenting foods to keep them from spoiling. Over a century ago, the Russian Nobel Prize winner Elie Metchnikoff theorized that “health could be enhanced and senility delayed by manipulating the intestinal microbiome with host-friendly bacteria found in yogurt.” Metchnikoff was ahead of his time with his view of probiotics benefits, but he also was aware that most citizens had regular access to probiotic foods.
Supplements play an important role when the diet is not adequate to supply our needs. In the case of probiotics, one's diet is the ideal source for probiotics. These are live bacteria and need to be carefully monitored, stored, and combined for the health benefits that one would be taking them for. At this time, supplements are not monitored in the U.S. the way that food or medication is. They fall under the Dietary Supplement Health and Education Act of 1994 (DSHEA). This requires that the dietary supplement or dietary ingredient manufacturer be responsible for ensuring that a dietary supplement or ingredient is safe before it is marketed. The only time that the U.S. Food and Drug Administration (FDA) may get involved is if action is needed to be taken against a manufacturer after the supplement is marketed and then found to be unsafe. This means that as much as we may know about probiotics, we can't be certain of the safety or content of the supplements available to us.
Unfortunately, the U.S. has no federal standards for probiotic supplements. Therefore, you run the risk of purchasing a product without any guarantee that it contains its advertised probiotic strains, that the strains are alive, or that the product is free from unhealthy ingredients. Therefore, it may be best to choose a brand-name probiotic that has research backing their effectiveness. Here are some examples:
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.
Probiotics are live microorganisms (bacteria or yeast) that have been shown to have a health benefit for humans. They are available in supplement form or in probiotic foods and drinks. Probiotics are thought to be akin to (and to increase the level of) the "good" bacteria found in your intestines. These "good" bacteria are thought to enhance our health through their support of our immune systems.
Scientists are investigating probiotics, and their combined effects, by trying to classify the probiotic benefits of ingesting specific probiotic strains and understanding their role in the digestive tract. At present, the methodological and ethical limitations of human studies still make it difficult to fully understand the mechanisms of action of probiotics, but some explanations are available. Nevertheless, benefits linked to the consumption of probiotic strains have already been suggested (e.g. helping to support the immune system, help support digestive health), and others are still being investigated.
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.
Because poor gut health is related to autoimmune responses like those found in rheumatoid arthritis (RA), probiotics have been a proposed treatment option for the condition. Only a few studies have been conducted in humans, and only one testing L. casei 01, a particular probiotic strain, was able to find a decrease in RA inflammation and progression of the disease.
Following a healthy and active lifestyle and eating a balanced diet are the best ways to foster a bountiful gut flora. Taking care of your gut flora can help with things like irritable bowel syndrome and chronic constipation, among other things. Even if you’re not sold on pursuing probiotics for your allergies, they’re good to consider if you’re experiencing any gastrointestinal issues.
×