Women’s health expert Dr. Amy Myers is a goop-trusted authority on subjects from autoimmunity and Candida to thyroid dysfunction; and she’ll be speaking IRL at our first wellness summit on June 10. Here, Myers helps us evaluate the increasing buzz around probiotics, and outlines the ins and outs of selecting a particular supplement (whether hers or other brands). Plus, we’ve rounded up our probiotic essentials, from inner beauty powders to favorite fermentation recipes, in one guide:


Additionally, it's a good idea to take note of the number of colony-forming units (CFUs) that are in the supplement you're considering, Angelone says. CFU count tells you the number of viable, active bacteria present in a tablet, she explains, and one billion (yes, seriously) is a typical dose. However, if you're struggling with a specific health condition, you may need more than that, Warren says. Your doctor can help you decide whether that's the case and may be able to steer you toward a good supplement to get you started. Here are a few to consider if you decide that probiotics are right for you.
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.
The second piece of research investigated whether patients should take probiotics to help the recovery of the natural gut bacteria after treatment with antibiotics. The evidence supporting this is not entirely clear and the FDA does not officially recommend it, but there are some reputable sources which discuss their use, such as this blog from Harvard Medical School. Research has suggested that up to 60% of healthcare professionals in the U.S. recommend taking probiotics, but is this justified and could it even be harmful?
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.

Notably, after someone was tagged a “persister” or “resister” clear patterns emerged on how probiotics would impact his or her indigenous microbiome and gut bacteria profile. "Although all of our probiotic-consuming volunteers showed probiotics in their stool, only some of them showed them in their gut, which is where they need to be," Eran Segal said in a statement. "If some people resist and only some people permit them, the benefits of the standard probiotics we all take can't be as universal as we once thought. These results highlight the role of the gut microbiome in driving very specific clinical differences between people."


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.
The second Elinav study, “Post-Antibiotic Gut Mucosal Microbiome Reconstitution Is Impaired by Probiotics and Improved by Autologous FMT” involved a mouse model and human patients. One cohort of mice and a parallel human group was given the same probiotic strain used in the first study to see if they had more success repopulating their gut microbiota after a round of antibiotics. Another “watch-and-wait” cohort didn’t take probiotics to assist gut microbiome recovery after antibiotic-related depletion. A third cohort was given an “autologous fecal microbiome transplant” (aFMT) which consisted of a patient’s own gut microbiota that had been collected before he or she started a cycle of antibiotics.
Hi Julia. I am 71 (male) and have had digestive issues for most of my life and no specific diagnosis. I eat fairly well, am not overweight, get gassy from many different foods and beverages. I have been using Culturelle for 9 months and feel the benefit from taking it is small. Your review leads me to believe there may be better choices. They certainly are not cheap but I will gladly pay for them if they give me results. I am probably going to try BlueBiotics unless you have other suggestions. My main question is since I live in Minnesota I will receive shipments in the summer with temps of up to + 100F and winters down to – 15F. Will this cause a decrease in product viability for this or other brands you recommended? Thank you for your help.
The current probiotic push lends itself to the question, "If humans got along fine without taking a probiotic supplement for thousands of years, why are they so important now?" Although there is no definitive answer to this question, there have been some significant cultural changes that have had an impact on the gut flora (the population of organisms that populate our intestines). These include the use of antibiotics, diets lacking in gut-healthy plant food, refrigeration and improved sterilization of foods. What we don't yet know is true is if probiotics actually turn around these changes and support the health of your gut flora.

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.
Overall, Garden of Life Primal Defense Ultra is one of my favorite probiotics! It uses a wide variety of potent probiotic strains that may help with daily digestion and specific stomach ailments. So it’s very flexible as far as probiotics are concerned. After personally testing out the product, my overall health felt improved, I wasn’t bloated, and I was digesting my food much better than normal.  Read the full review here… or click here to go buy it now!
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.
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. 

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.
Although some probiotics have shown promise in research studies, strong scientific evidence to support specific uses of probiotics for most health conditions is lacking. The U.S. Food and Drug Administration (FDA) has not approved any probiotics for preventing or treating any health problem. Some experts have cautioned that the rapid growth in marketing and use of probiotics may have outpaced scientific research for many of their proposed uses and benefits.
Taking probiotics can also help keep your urinary system working properly. While you might think that yeast imbalances or urinary tract issues are primarily women's problems, both are common in men as well, especially in those whose bacterial balance is off-kilter. Taking probiotics can help address these issues by encouraging the growth of good bacteria to crowd out unwanted yeast.10
B. Bifidum has also been shown to prevent intestinal pathogens or digestive disrupters from flourishing in the gut, essential in restoring the bacterial balance and optimizing digestion. Clinical research found it supports a significant reduction in IBS symptoms, an improvement in quality of life and even helps relieve occurrences of ulcerative colitis – a chronic inflammatory bowel disease. [1].

According to Bonnie Taub-Dix, MA, RD, CDN, founder of Better Than Dieting and author of Read It Before You Eat It, “We have more bacterial cells in our body than actual tissue, so you want as much “good” bacteria to be on your side. But not all probiotics are alike, and how your body reacts to them will not be the same as someone else who takes them.”


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.

Yes, they may help. Lebwohl says there are reputable studies that show a link between the use of probiotics and the reduction in IBS symptoms, citing this meta-analysis. It's estimated that 11 percent of the world population complains of symptoms like abdominal cramps, diarrhea, constipation, excessive gas and/or mucus in their stools. While for some the condition can be attributed to certain dietary triggers, others appear to be stress-related, which brings us to the heart of where many claims about the effectiveness of probiotics lie—in the gut-brain axis.


In seven people, however, these bacterial levels persisted for more than five months after the treatment ended. “We never expected they would survive more than a few weeks,” Walter says. A follow-up analysis determined that these seven people had begun the experiment with lower levels of B. longum in the first place. In other words, their gut ecosystems had a vacancy that the probiotic filled. That is exactly the kind of insight that clinicians need to create and recommend more effective probiotics. If a doctor knows that an individual with severe diarrhea has an undersized population of a particular beneficial microbe, for example, then prescribing the missing strain should increase the chance of a successful treatment.
There have been multiple additional studies which link stress to changes in gut bacteria, so there does appear to be some sort of link. But Lebwohl says it’s not enough to recommend widespread use in clinical practice. He referred to these as “hypothesis-generating studies,” which should lead to concrete clinical trials in which the probiotics are tested against a placebo. “These are important studies,” he says. “But it’s premature to call them practice-changing studies.”

The benefit of taking a probiotic supplement is that a supplement contains very specific bacteria known to have a beneficial effect on human health, and a positive impact on our gut microbiome. Taking a probiotic supplement has the added benefit of providing a specific and concentrated dosage of healthy bacteria, so you know you are getting a therapeutic, research-proven dosage every time.


Remember, while bacteria gets a bad rap, not all bacteria is bad: As New York City-based certified dietitian-nutritionist Gina Keatley tells Allure, plenty of microorganisms, including probiotics, actually help your body function. "Probiotics may help stabilize the protective barrier in our gut so bad microorganisms don't take root, stimulate the immune response, and aid in production of vitamins, such as vitamin K," she says. Sonya Angelone, a registered dietitian and Academy of Nutrition and Dietetics spokeswoman, adds that while we have more to learn about the role of probiotics, beneficial bacteria is understood to help crowd out harmful bacteria in our bodies. This good bacteria may also help lower cholesterol, aid in reducing colds and acute respiratory infections, and reduce the occurrence of vaginal yeast infections, she says.


In the United States, most probiotics are sold as dietary supplements, which do not undergo the testing and approval process that drugs do. Manufacturers are responsible for making sure they're safe before they're marketed and that any claims made on the label are true. But there's no guarantee that the types of bacteria listed on a label are effective for the condition you're taking them for. Health benefits are strain-specific, and not all strains are necessarily useful, so you may want to consult a practitioner familiar with probiotics to discuss your options. As always, let your primary care provider know what you're doing.
"I usually recommend Garden of Life, BioK or Megafoods brand," says Shapiro. "I also recommend starting with about 30 billion CFU and making sure your supplement has at least 12 different strains. And if you don't eat a diet high in fruits, vegetables, nuts, seeds, and whole grains that provide fiber for the probiotics to live off of, make sure you're the one you are taking contains prebiotics as well.
This Korean staple relies on lactic acid fermentation (also called lacto-fermentation) to turn cabbage or other vegetables into a spicy, pungent side dish that's packed with vitamin C. Order it at Korean restaurants or buy it in the refrigerated section of your grocery store (King's Kimchi is widely available at Walmart). For some guidance on making your own, turn to The Art of Fermentation ($23; amazon.com). Then, use it to spike veggie-laden rice bowls, top on soup, or serve alongside meat.

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Yes, they may help. Lebwohl says there are reputable studies that show a link between the use of probiotics and the reduction in IBS symptoms, citing this meta-analysis. It's estimated that 11 percent of the world population complains of symptoms like abdominal cramps, diarrhea, constipation, excessive gas and/or mucus in their stools. While for some the condition can be attributed to certain dietary triggers, others appear to be stress-related, which brings us to the heart of where many claims about the effectiveness of probiotics lie—in the gut-brain axis.
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].
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].
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.
Gut flora makes up 70 to 80 percent of the human immune system. Too much bad bacteria can inflame and destroy intestinal walls, enter the bloodstream, and trigger a multitude of health issues — constipation, depression, skin problems, autoimmune disease, and even bad breath. Adding good bacteria protects the digestive tract from the harmful bacteria in sugars, pesticides, and saturated fats.
In these cases, IBS is essentially just TMI. “For the colon to be functioning properly, it needs to be contracting and relaxing in a way that is conducive to regular bowel movements that occur at predictable times and don’t occur too frequently or too rarely," Lebwohl says. "And the bowel needs to be giving infrequent feedback to the brain. People should not be getting updates from their bowel in terms of cramps or the feeling of having to have a bowel movement too often. Yet, people with IBS get very frequent unsolicited ‘progress reports’ from the bowel.”
This dairy-free, gluten-free, vegetarian probiotic delivers live microorganisms, protected in stomach acid-resistant capsules to ensure effective delivery throughout your digestive system, from the stomach through your small intestines. The result is the repair and sustained maintenance of your intestinal micro-ecology, which in turn helps support healthy immune response and bowel regularity.
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.
Digestive Advantage is one of the better probiotics available today. With 2 billion live cells in each capsule, it makes for a good daily probiotic for digestive and immune health. This probiotic claims that it can survive in your digestive system up to 10x better than yogurt. If this fact holds true, taking a supplement like this is much quicker and possibly more efficient than eating spoonfuls of yogurt everyday!  Overall, Digestive Advantage succeeds in being a great probiotic that’s a great value and can be taken every day!  Read the full review here… or click here to go buy it now!
The second Elinav study, “Post-Antibiotic Gut Mucosal Microbiome Reconstitution Is Impaired by Probiotics and Improved by Autologous FMT” involved a mouse model and human patients. One cohort of mice and a parallel human group was given the same probiotic strain used in the first study to see if they had more success repopulating their gut microbiota after a round of antibiotics. Another “watch-and-wait” cohort didn’t take probiotics to assist gut microbiome recovery after antibiotic-related depletion. A third cohort was given an “autologous fecal microbiome transplant” (aFMT) which consisted of a patient’s own gut microbiota that had been collected before he or she started a cycle of antibiotics.
The Strand Similar to multivitamins, not all probiotics are created equal. Different probioitcs have different bacteria strains with varying benefits; and some probiotics may contain more than one strain, so it’s important to do your research. Some strains may help with gastrointestinal issues like diarrhea, while others may not have any effect on the GI tract at all, according to Keri Gans, RDN, author of The Small Change Diet. If you’ve made the decision to take a probiotic supplement but you’re unsure about which strain to take, ask your doctor or a registered dietitian for a recommendation. “You most likely will not have any negative side effects from using the wrong strain, but you may also not see any benefits,” says Gans.

When looking at the list of possible causes, it is no surprise that gut function plays a role in brain fog. The gastrointestinal (GI) tract is in direct and indirect communication with the brain, and microbes in the gut can affect, for better or for worse, the types of communication that occur between the GI tract and the brain. Additionally, harmful products from pathogens in the gut can travel to the liver, overloading the liver and causing toxins to be circulated to the brain and contributing to brain fog.
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.
Uh, no. “There have been studies that suggest a theoretical link between the microbiome and even changing the microbiome, and changes in the brain,” Lebwohl tells me. He specifically points to this study, in which healthy women with no gastrointestinal issues had their brains imaged before and after a month of consuming yogurt products containing probiotics twice daily.
As a world-renowned neurologist and nutritionist, Dr. David Perlmutter has become somewhat of a household name when it comes to the linkage between what we eat and how we feel. He is known as “The Empowering Neurologist” and has been featured on the Doctor Oz Show, CNN, and NPR as well as in prominent publications like The New York Times, Forbes, Time Magazine, and the Wall Street Journal. If that wasn’t enough to spark your interest, Dr. Perlmutter is also the award-winning author of the Grain Brain Whole Life Plan, Brain Maker, and Grain Brain, all of which have become international bestsellers.
How is it that probiotics are such a ubiquitous trend in the wellness scene but subject to tons of misinformation all the same? Consider the myth, for example, that the only appeal of replenishing your good bacteria is smoother digestion. On the contrary, the benefits of probiotics abound: from a boosted mood and better skin to a healthier immune system.
Diversity of strains - research has demonstrated that bacteria prefer to colonize in different parts of your digestive tract, where there are various ecological niches. The more probiotic strains you ingest, the more coverage you’ll provide for each of these niches. Each strain of bacteria also has its own different purpose, so choosing a formula with many different strains gives you that many more benefits.
That's because issues that can be treated with probiotics stem from specific imbalances in the amount of certain bacterial strains, according to Elena Ivanina, M.D., a gastroenterologist at Lenox Hill Hospital. "Therefore, if someone decides to supplement a particular strain of Lactobacillus, but they already have enough of that strain in their gut and their disease does not stem from a lack of Lactobacillus, then they will not have a response." Makes sense, right?
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.
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.

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.

"The name itself is derived from the Latin 'pro-' meaning 'for' and the Greek '-biotic' meaning 'life,'" explains Jeannel Astarita, skincare expert and founder of Just Ageless NYC Wellness and Medspa. "Probiotics are the helpful bacteria that live primarily in your gut and play a crucial role in your overall health by fighting pathogens and yeast that lead to a weakened immune system."

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.∗
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.
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