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Fermenting a cucumber into a pickle amps up a cuke's powers, infusing the crunchy veggie with probiotics. Like sauerkraut, not all pickles offer the good bacteria, though. Look for those made with brine (salt and water) rather than vinegar. These brands will list "live cultures" on the label (like Bubbies). You can also use water, salt, and spices to naturally culture pickles and other veggies—like beets, green beans, and carrots—at home with delicious results. One warning: remember that pickles are salty—one dill can easily offer up more than 10% of your sodium needs in a day.
The prebiotic comes before and helps the probiotic, and then the two can combine to have a synergistic effect, known as synbiotics. A prebiotic is actually a nondigestible carbohydrate that acts as food for the probiotics and bacteria in your gut. The definition of the effect of prebiotics is the selective stimulation of growth and/or activity(ies) of one or a limited number of microbial genus(era)/species in the gut microbiota that confer(s) health benefits to the host. The health benefits have been suggested to include acting as a remedy for gastrointestinal (GI) complications such as enteritis, constipation, and irritable bowel disease; prevention and treatment of various cancers; decreasing allergic inflammation; treatment of nonalcoholic fatty liver disease (NAFLD), and fighting immune deficiency diseases. There has also been research showing that the dietary intake of particular food products with a prebiotic effect has been shown, especially in adolescents, but also tentatively in postmenopausal women, to increase calcium absorption as well as bone calcium accretion and bone mineral density. The benefits for obesity and type 2 diabetes are growing as recent data, both from experimental models and from human studies, have shown particular food products with prebiotics have influences on energy homeostasis, satiety regulation, and body weight gain.
We also found strains linked to five other health benefits like weight loss and lowering cholesterol. We feature options for those cases below, but they aren’t top picks because those use cases aren’t as heavily researched as immune health or IBS relief. Still, chances are any probiotic supplement is going to make some improvement to your digestive health, so don’t be afraid to experiment.
Vitamin Bounty’s probiotic contains a variety of well-studied strains and a competitive 25 Billion CFU. It also contains a natural prebiotic resistant starch, rice flour, to fuel the strains this probiotic supplies. Over 95% of Pro 25’s strains were still active and viable, the second highest observed strain viability out of all probiotics reviewed-to-date!
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].
It’s important to note that there are different types of strains of probiotics. The probiotics benefits of one probiotic strain may be completely different from the health benefits seen from another probiotic. If you want to use probiotics to address a specific health concern, it’s vital to select the right probiotic for the right condition — or you can consume a wide range of probiotics in your food to be covered.
​​​​​​AZO Complete Feminine BalanceTM is a daily probiotic supplement designed for the unique needs of women. Many everyday things can throw off your balance (stress, sex, pregnancy, aging, even medications! This product supports your feminine health and maintain a healthy pH so that you can own your day! It contains INTELLIFLORATM: a probiotic blend of four lactobacilli that are associated with vaginal health* (Lactobacillus crispatus LBV 88, Lactobacillus rhamnosus LBV 96, Lactobacillus jensenii LBV 116, and Lactobacillus gasseri LBV 150.)  The INTELLIFLORATM blend has been shown in clinical studies to help restore and maintain the healthy balance of the vaginal microbiota.*
The Number of CFUs The quality of a probiotic supplement has more to do with strains and how many CFUs it provides. (CFU stands for colony forming units, and it refers to the amount of live microorganisms in your supplement.) Although recommendations may vary, Gans says to look for probiotics with at least 1 billion CFUs: “Doses will typically range from 1 billion to 10 billion CFUs for adults; although doses for children are often under 1 billion.”

Prebiotics and supplementary ingredients — For probiotic bacteria to grow, they also need prebiotics. High-quality probiotic supplements have both prebiotics and other ingredients designed to support digestion and immunity. Examples of these ingredients are (preferably fermented) flaxseed, chia seed, cañihua seed, astragalus, ashwagandha, hemp seed, pumpkin seed, milk thistle, peas, ginger, mung bean and turmeric.
Selecting a multi-strain probiotic is also consistent with the theory that filling your gut with enough good bacteria outcompetes any bad bacteria for the same space and resources. In your gut, the more diversified the good bacteria, the harder it is for the baddies to gain a foothold. With all this in mind, we only looked at supplements containing multiple strains of bacteria.
Better Health Review ranks Ultimate Flora as the most effective probiotic supplement. It contains 30 billion active bifidobacteria for colon health, and 20 billion lactobacilli and lactococcus cultures for the small intestine. According to Better Health Review, it contains all natural ingredients. It earns a perfect 5 score from Better Health Review, and the magazine “Vitamin Retailer” voted it best two years in a row.
One of the best-studied effects of probiotics has been on the reduction in diarrhea severity and duration. Probiotics can prevent as well as reduce duration of several types of diarrhea. Lactobacillus has been found to be a safe and effective treatment for children with acute infectious diarrhea. Certain probiotics may also offer a safe and effective method to prevent traveler’s diarrhea, but research in this area is emerging.

Made by fermenting the juice of young coconuts with kefir grains, this dairy-free option for kefir has some of the same probiotics as traditional dairy kefir but is typically not as high in probiotics. Still, it has several strains that are great for your health. Coconut kefir has a great flavor, and you can add a bit of stevia, water and lime juice to it to make a great-tasting drink.
​​​​​​AZO Complete Feminine BalanceTM is a daily probiotic supplement designed for the unique needs of women. Many everyday things can throw off your balance (stress, sex, pregnancy, aging, even medications! This product supports your feminine health and maintain a healthy pH so that you can own your day! It contains INTELLIFLORATM: a probiotic blend of four lactobacilli that are associated with vaginal health* (Lactobacillus crispatus LBV 88, Lactobacillus rhamnosus LBV 96, Lactobacillus jensenii LBV 116, and Lactobacillus gasseri LBV 150.)  The INTELLIFLORATM blend has been shown in clinical studies to help restore and maintain the healthy balance of the vaginal microbiota.*
Yogurt: It can contain Streptococcus thermophilus, Lactobacillus bulgaricus, L. acidophilus, and Bifidobacterium bifidum. Research has shown links with yogurt to have positive effects on the gut microbiota and is associated with a reduced risk for gastrointestinal disease and improvement of lactose intolerance (especially among children), type 2 diabetes, cardiovascular disease, allergies and respiratory diseases, as well as improved dental and bone health.
Selecting a multi-strain probiotic is also consistent with the theory that filling your gut with enough good bacteria outcompetes any bad bacteria for the same space and resources. In your gut, the more diversified the good bacteria, the harder it is for the baddies to gain a foothold. With all this in mind, we only looked at supplements containing multiple strains of bacteria.
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!
Probiotics are clearly incredibly supportive, but they can't do their work alone. To make sure that you're getting the most out of your microbes, it's important that you give them the support they need to work. You've got lots of options for supporting your gut health, from dietary changes to probiotic supplementation, but make sure you're at least covering the following bases.
"Contrary to the current dogma that probiotics are harmless and benefit everyone, these results reveal a new potential adverse side effect of probiotic use with antibiotics that might even bring long-term consequences," Elinav says. "In contrast, replenishing the gut with one's own microbes is a personalized mother-nature-designed treatment that led to a full reversal of the antibiotics' effects."
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.
As with other types of supplements, scientists are still discovering the full potential of probiotics. However, when taken regularly, it is believed that they help support digestive health by helping maintain the balance of beneficial and non-beneficial bacteria in your digestive tract. Having a natural balance of good bacteria in the digestive tract can help defend against occasional digestive issues. In addition, probiotics play an important role in supporting immune health, since 70% of the body's immune system is found in the digestive tract.∗
Probiotics have direct and indirect effects on your immune system. They can help tip an imbalance in an immune response, such as in seasonal allergies, to a more balanced state. Probiotics benefits have direct and indirect effects on your nervous and endocrine systems, too, and are part of your enteric nervous system. They can influence every system in your body. The amount of probiotic pills and supplements shown to be beneficial in research for various conditions differs based on the population and condition studied, so no blanket recommendations can be made.
Better Health Review named Dr. Ohhira’s Probiotics 12 Plus on its list of the top probiotic supplements on the market. It contains less than a billion active probiotic cells per dosage, but it adds vitamins, minerals and other micronutrients for optimal health. It claims to be 100 percent vegetarian. Better Health Review gives Dr. Ohhira’s Probiotics 12 Plus a rating of 3.5 on a scale of 5.

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.
The side effects of antibiotic use are often not trivial. Many people experience discomfort and a change in bowel habits, but some experience more severe infections, such as opportunistic colonization of the gut with bacteria such as Clostridium difficile (C.diff), which affected half a million Americans in 2015 and was directly responsible for at least 15,000 deaths.
Vitamin Bounty’s probiotic contains a variety of well-studied strains and a competitive 25 Billion CFU. It also contains a natural prebiotic resistant starch, rice flour, to fuel the strains this probiotic supplies. Over 95% of Pro 25’s strains were still active and viable, the second highest observed strain viability out of all probiotics reviewed-to-date!
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:

If you’re giving probiotics to a baby under two years old, you want to look for specific strains, though, that are better suited to such young microbiomes. For babies, these are the strains of Lactobacillus to look for: rhamnosus, casei, paralisei, gasseri, salvarius. And for Bifidobacterium: infantis, bifidum, longum, breve, lactis. If you’re breastfeeding, you can put probiotics on your breast, or you can heat up formula and put probiotics in it, or wet your finger and dip it in the probiotics powder and let your baby suck on your finger.


From Lactobacillus acidophilus to Bacillus Coagulans, the BlueBiotics blend is a veritable list of the most researched and proven probiotic bacteria known to science. And recent advances on the blend have made it the only full-spectrum probiotic supplement on the market, as it contains strains which are typically not available to the general public (Bacillus Coagulans and S. boulardii). The CFU count alone is remarkable enough, leaving most comparable spectrums in the dust… HOWEVER even more surprisingly our tests showed that a whopping 98% of the probiotic colonies in BlueBiotics were still alive, making this BY FAR the most effective probiotic supplement that we have ever reviewed. Also, because of the diverse pool of strains in BlueBiotics, users have reported a wide variety of benefits from weight loss, to increased energy, improved digestive health and cognitive function. Many of our staff switched to these probiotics, as well as myself and my family.
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.
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.
Lacto-bacillus plantarum: If you’ve ever heard of the beneficial effects of fermented foods (pickles, sauerkraut, kimchi, etc.), then you’ve heard of this powerful probiotic, which may help improve the symptoms of IBS, gluten intolerance, soy allergies, and Crohn’s disease. This is also one of the most antibiotic-resistant probiotics, which is especially important if you have taken antibiotics recently.

In the new study, the researchers analyzed information from 15 healthy volunteers who took either a probiotic product containing 11 strains of bacteria, or a placebo, for four weeks. The participants also underwent colonoscopies and upper endoscopies before they took the probiotics or the placebo, and again after the four-week treatment period. (An upper endoscopy looks at the upper part of the digestive tract.) During these procedures, the researchers took samples from inside participants' guts.

The Golive Berry Probiotic and Prebiotic Supplement Blend is perfect for tossing in your bag or keeping in your desk. Each packet includes 15 billion CFUs and 15 different probiotic strains. It also has a soluble fiber prebiotic to promote the growth of good bacteria in your body. Each packet contains 30 calories and comes in five flavors including pomegranate, melon cucumber, citrus blueberry, and a flavorless option. It can be mixed in any hot or cold drink, but we recommend tossing the flavored packet into a bottle of water. You’ll get 10 packets in each order.
This smooth, slightly tangy, and sippable yogurt contains a dozen different types of live active cultures. It's also 99% lactose-free, making it easier to digest for those with intolerant tummies. "If you have lactose intolerance, start slowly on kefir as a test. If you have no symptoms, go ahead and slowly increase your intake," advises Tallmadge. Plus, with 8 to 11 grams of protein per cup (depending on the brand), it can help fill you up for around 100 calories.
Next time you pack your travel beauty bag, slip a shelf-stable probiotic in there to preempt bathroom emergencies, Fasig says. Look for one that contains Lactobacillus acidophilus, Lactobacillus sporogenes, Bifidophilus bifidum, and Sacchromyces boulardii strains ($20, amazon.com), which Fasig says can improve your intestinal health to fix issues with constipation or diarrhea.

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.
Make sure dosages are listed in CFU, colony forming units. (Most brands list CFU in billions now: so 30 billion CFU, 100 billion CFU, and so on.) For one, this means that the bacteria strains are living, which is essential. When you’re looking at the cost of products, be sure to look at the cost per unit. I spoke to a woman the other day who had bought probiotics that had 2 billion CFU per capsule. In comparison, to get the 30 billion CFU I recommend, she’d have to take essentially half of her bottle to get the same dosage as one of our capsules.
Most probiotics are like what is already in a person's digestive system. Some probiotics have been used for a very long time throughout history, such as in fermented foods and cultured milk products. These don't appear to cause illness. But more study is needed on the safety of probiotics in young children, the elderly, and people who have weak immune systems.

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.


As of now, the most comprehensive meta-study (a study of different studies) has not been able to decisively identify any particular strain of bacteria that is specifically useful to treat seasonal allergies. Some studies contradict each other on which bacteria can treat grass pollen, and other studies will find that those strains the first two studies examined weren’t nearly as effective in their own trials.

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.
Make sure dosages are listed in CFU, colony forming units. (Most brands list CFU in billions now: so 30 billion CFU, 100 billion CFU, and so on.) For one, this means that the bacteria strains are living, which is essential. When you’re looking at the cost of products, be sure to look at the cost per unit. I spoke to a woman the other day who had bought probiotics that had 2 billion CFU per capsule. In comparison, to get the 30 billion CFU I recommend, she’d have to take essentially half of her bottle to get the same dosage as one of our capsules.

Other uses. Many other claims are made for probiotics—that they lower cholesterol, alleviate allergic skin conditions (like eczema), treat ulcers and urinary tract infections, improve vaginal health, reduce the risk of colon cancer, ease anxiety and depression, and ward off traveler’s diarrhea. Good evidence to support these claims is lacking. Research on probiotics for weight loss has yielded inconsistent results, and even studies with positive results have mostly found very small benefits, as was seen in an analysis of 15 clinical trials in Obesity Reviews in 2018.


Minerals And Extracts – Many probiotics, especially those marketed for women, also contain blends of vitamins, minerals, and plant extracts for optimal results. In some cases, these blends can be so inclusive that they actually replace your traditional multi-vitamin, and can be an excellent source of nutrition for women that don’t receive enough vitamins or nutrients in their basic diets.
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.
Back to the question of what are probiotics: There are five main types, each in its own classification called a genus. Within each genus there are multiple species, and within those species there are multiple strains. For example, Lactobacillus is a very common genus of probiotics. Within that genus are numerous species, such as rhamnosus. The genus and species of a microbe are always italicized, making it easy to know that a microbe is involved. In a species such as Lactobacillus rhamnosus (often abbreviated L. rhamnosus), there are many strains. An example of the name of a strain is L. rhamnosus GR-1.
Let’s start at the very beginning: probiotics are bacteria. We know what you’re thinking, bacteria cause infections and are just generally kind of gross. Well, in some aspects, you’re absolutely right. But when it comes to your digestive and feminine health, some bacteria are teeny tiny miracle workers that can make all the difference in the way you feel!
Selecting a multi-strain probiotic is also consistent with the theory that filling your gut with enough good bacteria outcompetes any bad bacteria for the same space and resources. In your gut, the more diversified the good bacteria, the harder it is for the baddies to gain a foothold. With all this in mind, we only looked at supplements containing multiple strains of bacteria.
Proponents claim that probiotics (meaning “for life,” as opposed to antibiotics) confer health benefits primarily by rebalancing the normal microflora in the large intestine (colon). There are many general types of bacteria used as probiotics (two common ones are Lactobacillus and Bifidobacterium), and many different species as well as strains within species. They have different physiological effects—and thus possibly different health benefits (as well as possible risks). Some yeasts, such as Saccharmyces, can also act as probiotics.
While more research is necessary to truly understand the widespread benefits of different probiotic strains, we do know that not all probiotics are created equal. The Lactobacilli, for instance, live in our digestive, urinary and genital systems and can be found in some fermented foods like yogurt. Bifidobacteria normally live in the intestines as lactic acid bacteria, and are also found in fermented foods. According to nutrition expert Alex Caspero, RD, “For certain conditions, you want to ensure you are taking the strand that is most likely to benefit you.” Here is a simple breakdown to help you determine the best probiotic for you.
Even for those without an urgent problem, probiotics can help with overall digestive management. Challa argues in his book, Probiotics For Dummies, that good bacteria help "crowd out" bad bacteria. That's because the intestine is lined with adherence sites where bacteria latches on. If the sites are populated with good-for-you microbes, there's no place for a harmful bacterium to latch on.
Some people prefer probiotic supplements over foods, but Dr. Cresci notes that probiotic foods are a better choice. In particular, fermented foods — like yogurt, kefir (a yogurt-like beverage), kombucha (fermented black tea), sauerkraut (refrigerated, not shelf-stable), kimchi (made from fermented cabbage) and tempeh and miso (made from fermented soybeans) — provide a nourishing environment in which healthful bacteria thrive and release an important byproduct: short-chain fatty acids.
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.
Oral health. An increasing number of probiotic lozenges and gums are promoted for oral health—to reduce periodontal disease, throat infections, and bad breath, for example. There’s preliminary evidence that certain strains may have some benefits, but commercial products may not have the same strains and formulations as those tested in published studies.
Microbes are tiny organisms (bacteria, viruses, parasites, or fungi) -- so tiny that millions can fit into the eye of a needle -- that are so powerful that an imbalance in the body is related to numerous diseases. These microorganisms can be found in almost every part of the human body, living on the skin, in the nose, and in the gut. There are trillions of these microorganisms in our bodies. They outnumber human cells by 10 to one, but due to their small size, they only make up 1%-3% of a body's total mass.
Bacteria in your digestive tract can be good or bad, according to the website Best Probiotic. It quotes the Royal Academy of Medicine England as blaming an imbalance between good and bad bacteria for causing 80 percent of all degenerative diseases. Probiotic supplements with "good" bacteria have become increasingly popular. They can aid the immune system, digestion and vitamin absorption, as well as prevent diarrhea and irritable bowel syndrome. The website Women to Women recommends probiotics that combine saccharomyces, lactobacillus acidophilus and bifidobacteria in the billions. MayoClinic.com also recommends lactobacillus and advises looking for products that contain live, active cultures. You should always check with your doctor before adding any supplements to your diet.

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.”
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.
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