This is one of the newer areas of probiotic research. Described as the “gut-brain axis,” researchers believe that the communication between the gut and the brain affects not just physical but also mental health and behavior. For example, a recent study found that probiotics can reduce anxiety, relieve stress and improve mental outlook. Another study found that the probiotics L. helveticus and Bifidobacterium longum reduced depression, anger, hostility and self-blame and improved problem-solving ability. Another study showed a difference in brain activity between women consuming yogurt and those consuming a placebo. More research needs to be done to confirm the effect of probiotics on mental and emotional health.
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.

There’s good and bad bacteria in there (fascinating fact: an estimated 100 trillion bacteria live inside your digestive tract): When the good outweighs the bad, your immune health soars; when the bad overpowers good, you get sick. You have diarrhea. Your immune system tanks. Your IBS, lactose intolerance, and other gut problems are exacerbated. It throws your entire system out of whack.


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.

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.


As one of the best probiotics for weight loss, there have been a slew of studies demonstrating just how powerful this strain of bacteria may be when it comes to your waistline. For instance, one study in the British Journal of Nutrition showed that taking Lactobacillus gasseri daily led to significant reductions in body weight and body fat compared to a control group, with participants losing up to 8.5 percent body fat over a 12-week period. (13)
Smits H.H., Engering A., van der Kleij D., de Jong E.C., Schipper K., van Capel T.M., et al. (2005) Selective probiotic bacteria induce IL-10-producing regulatory T cells in vitro by modulating dendritic cell function through dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin J Allergy Clin Immunol 115: 1260–1267 [PubMed] [Google Scholar]

When you nosh or swallow a probiotic, it doesn't take up permanent residence in your intestinal ecosystem with the bacteria that's there already, says Hutkins. It might help crowd out a microorganism that's making you sick (which is likely why probiotics have proven most useful against infectious diarrhea), but it eventually just passes through the gut. That's why it's impossible to take too many; you'll just poop them out. This in-and-out nature also means that if you're aiming for a health benefit, you need to ingest them almost daily.
^ Shane AL, Cabana MD, Vidry S, Merenstein D, Hummelen R, Ellis CL, Heimbach JT, Hempel S, Lynch SV, Sanders ME, et al. (2010). ": Guide to designing, conducting, publishing and communicating results of clinical studies involving probiotic applications in human participants". Gut Microbes. 1 (4): 243–253. doi:10.4161/gmic.1.4.12707. PMC 3023606. PMID 21327031.
But put down your kombucha, friends, because science has not quite proven that's the case yet, says Robert Hutkins, Ph.D., a scientist at the Nebraska Food for Health Center in Lincoln. Of the hundreds of identified probiotic strains, studies have only ID'd a handful that are helpful in treating specific conditions. And there's no evidence they have much effect on the microbiota of healthy individuals, per recent studies.
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.

The gut microflora of every individual consists of various microorganisms (bacteria, yeast and fungi) that live in the intestinal tract. When the intestinal microflora is out of balance, that imbalance may affect overall health. This balance can be disturbed during times of stress, with age, in menopause, when taking medications, with an unbalanced diet, and in the event of acute or chronic intestinal disease.1,2,3

We’ll start with the headliner: the BIO-tract peral, which packs the equivalent of 75 billion CFUs into one tiny, filler-free, 5-billion CFUs pearl. The trick is in protecting those 5 billion CFUs over an 8 to 10-hour period, so they bypass your acidic stomach and reach your intestinal tract, alive and well, allowing you to experience the full and multitudinous benefits of plentiful and beneficial gut bacteria.
No matter how many superfoods you eat, your body won’t be able to benefit from them if your gut environment isn’t teeming with healthy bacteria. You see, enzymes and digestive bacteria help to break down the food you eat into molecules that make their way into your bloodstream to nourish your body. Inadequate or unbalanced microbial populations in the gut can derail this process and can even lead to malabsorption of critical nutrients. 
Made from fermented cabbage and other vegetables, sauerkraut is not diverse in probiotics but is high in organic acids (what gives food its sour taste) that support the growth of good bacteria. Sauerkraut is extremely popular in Germany today. It is high in vitamin C and digestive enzymes. It’s also a good source of natural lactic acid bacteria, such as lactobacillus.
In 1907, Russian zoologist Élie Metchinkoff theorized that the gut microbiome could be modified by replacing the harmful bacteria in the digestive tract with beneficial strains instead. He also suggested that the aging process stemmed from the production of toxic substances by specific strains of bacteria in the gut. He believed that fermented foods like sour milk could help lower the pH of the intestinal tract and block the growth of bacteria.
The first major finding was that many people were essentially resistant to any effect from probiotics and their gut microbiome did not change after taking them.  Of 19 people in the study taking probiotics consisting of 11 of the most commonly found strains, only 8 had any notable colonization of their gut with the bacteria in the probiotics, with 3 people considered to have significant colonization and 5 people with "mild" colonization.
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.
Probiotics are safe in the amounts you normally find in food. In general, most healthy adults can safely add foods or dietary supplements that contain probiotics to their diets. Some individuals might experience gas (flatulence), but that generally passes after a few days. But which strains of bacteria are most helpful or which doses are best isn't always known. And if you are lactose intolerant, you can experience stomach discomfort if you try to get your probiotics from dairy products. In that case, consider using a dairy-free probiotic.
She totally did, but you may have noticed that you don't see those yogurt commercials anymore. That’s because in 2010, the Federal Trade Commission in conjunction with 39 states' attorney generals banned those ads, finding that the Dannon Company had no scientific evidence to back up their claims,. Dannon had to pay $21 million to resolve the associated investigations.
Fecal microbiota transplants (FMT), or "poop transplants," can treat a type of gut disorder with an infusion of diverse bacteria from a healthy digestive system, distilled from a donor's poop. This helps to correct imbalances of microbial diversity when the gut microbiome is dominated by the bacteria Clostridium difficile (C. diff), which can lead to serious gut disorders.  

Diarrhea is a change is the frequency and looseness of bowel movements. Symptoms associated with diarrhea are cramping, abdominal pain, and the sensation of rectal urgency. Causes of diarrhea include viral, bacterial, or parasite infection, gastroenteritis, food poisoning, and drugs. Absorbents and anti-motility medications are used to treat diarrhea.


Probiotics also seem to ameliorate irritable bowel syndrome, a chronic disease characterized by abdominal pain, bloating, and frequent diarrhea or constipation (or a mix of the two). A 2014 review of more than 30 studies, published in the American Journal of Gastroenterology by an international team of researchers, determined that in some cases, probiotics help to relieve the symptoms of irritable bowel syndrome for reasons that are not entirely clear, although it may be that they impede the growth of harmful microbes. The researchers concluded, however, that they did not have enough data to recommend any particular strains of bacteria. Microbiologists often caution that a promising study on a single strain of a particular species of bacteria should not be taken as proof that all probiotics work equally well. “Bacterial strains are so genetically different from one another, and everybody has a different gut microbiota,” Allen-Vercoe says. “There will probably never be a one-size-fits-all probiotic.”
Probiotics stick around for a while, though for how long isn’t precisely clear. You have to keep taking them to continue to reap the benefits. Further, getting a wide variety of strains into your system is beneficial. “Periodically mixing up your probiotic supplement is also a good way to ensure that you get different health-building strains in your health regime,” says Dr. Cook.

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.
Once you have identified the right strain or strains, it's important to find a product that provides a dose that's been shown to be effective, and that contains it's labeled dose (ConsumerLab.com tests have found some probiotic supplements to contain less than half the amount of organisms claimed on the label!) To get test results for popular products, plus additional tips for choosing a probiotic supplement, see the Probiotic Supplements Review >>  

One review of probiotics benefits for necrotizing enterocolitis was bold enough to say, “The results confirm the significant benefits of probiotic supplements in reducing death and disease in preterm neonates. The … evidence indicate that additional placebo-controlled trials are unnecessary if a suitable probiotic product is available.” Regarding sepsis in developing countries (where it is overwhelmingly more common), a 2017 randomized, controlled trial claims that a large number of these cases “could be effectively prevented” if mothers are given a synbiotic (probiotic and prebiotic together) that contains the probiotic strain L. plantarum.
They then tested different doses of the 10-bacterial probiotic blend in mice, as well as in a slurry of human feces meant to mimic the environment of a human digestive system. The scientists found that even single doses maintained the healthy microbial balance and increased SCFA production in both the mice and the feces medium, the researchers reported.
Survival past stomach acids - probiotic powder in capsule form is ill prepared when it comes to protecting the delicate bacteria from being pulverized by the harsh environment of the stomach acids. Worse, most of the organisms tend to die off before they reach their intended destination due to moisture that gets trapped between the capsule shell and the powder.
Gut Check: Exploring Your Microbiome. Archived Coursera course by Prof. Rob Knight. Imagine if there were an organ in your body that weighed as much as your brain, that affected your health, your weight, and even your behavior. Wouldn’t you want to know more about it? There is such an organ — the collection of microbes in and on your body, your human microbiome.
The intestinal tract is the organ in the body that digests and absorbs food. It is populated by trillions of bacteria that are required for keeping the body healthy. These bacteria can be affected by a number of aspects including antibiotic use, a diet low in fibre, fruit and vegetables and infective diarrhoea. When this occurs, probiotics can help to reset the balance.
"Many chronic health problems and inflammatory diseases are caused by a damaged microbiome where the good bacteria is overrun by the harmful bacteria and can't reinforce the gut walls, which results in increased intestinal permeability where bacteria and toxins leak through the intestines into the bloodstream triggering a system-wide immune response of inflammation that is a part of our body's natural healing cycle."
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.
No matter how many superfoods you eat, your body won’t be able to benefit from them if your gut environment isn’t teeming with healthy bacteria. You see, enzymes and digestive bacteria help to break down the food you eat into molecules that make their way into your bloodstream to nourish your body. Inadequate or unbalanced microbial populations in the gut can derail this process and can even lead to malabsorption of critical nutrients. 
^ Newlove-Delgado TV, Martin AE, Abbott RA, Bethel A, Thompson-Coon J, Whear R, et al. (2017). "Dietary interventions for recurrent abdominal pain in childhood". Cochrane Database Syst Rev. 3: CD010972. doi:10.1002/14651858.CD010972.pub2. PMID 28334433. Overall, there is some evidence to suggest that probiotics may be effective in the treatment of RAP, in terms of improving pain in the shorter term. Clinicians may therefore consider probiotic interventions as part of themanagement strategy for children with RAP (Recurrent Abdominal Pain). However, we were unable to recommend the optimum strain and dosage of probiotic based on this review. The evidence for the effectiveness of probiotics was based largely on shorter-term outcomes. Further trials are required to assess whether improvements in pain are maintained over the longer term; these trials should also consider the importance of using validated and consistent scales to measure pain and other outcomes.
Irritable bowel syndrome (IBS) is a multisymptom GI disorder with unclear etiology and pathogenesis. Changes in GI microflora in IBS patients have been reported by a number of investigators [Kassinen et al. 2007; Shanahan, 2007]. Recently, reports on variable prevalences of small intestinal bacterial overgrowth (SIBO) in IBS have been published [Posserud et al. 2007; Lin, 2004]. IBS symptoms such as bloating or flatulence have been attributed to possible alterations in the intestinal microflora and probiotics have been used empirically to treat these difficult symptoms [Kim et al. 2003, 2005]. Postinfectious IBS may begin after a bout of acute gastroenteritis suggesting that altered microflora or induction of an altered inflammatory or immune state in the bowel may lead to altered bowel function and IBS symptoms [Collins et al. 2009]. An increase in lymphocytes and an increase in pro-inflammatory cytokines have been described [Spiller et al. 2000].
Did someone say chocolate? Yes, you can have your probiotics and eat your chocolate too with these Digestive Advantage probiotic bites from Schiff. Easy to pop, they contain BC20, a probiotic that the manufacturer says survives stomach acid better than other probiotics and even yogurt. Made with dark chocolate, they contain just 30 calories per serving (one chew) and no artificial colors, flavors or preservatives.
Probiotics, or beneficial gut microbes, influence many functions in your body. In addition to your immune health, researchers have found they affect your body weight, energy and nutrition, and your brain, both psychologically and neurologically. Your microflora impacts the expression of your genes, too, which can have a powerful effect on your health.*
"Many chronic health problems and inflammatory diseases are caused by a damaged microbiome where the good bacteria is overrun by the harmful bacteria and can't reinforce the gut walls, which results in increased intestinal permeability where bacteria and toxins leak through the intestines into the bloodstream triggering a system-wide immune response of inflammation that is a part of our body's natural healing cycle."
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.
Some of their benefits are universal, no matter your age or gender: supporting gut health, healthy skin, weight management, and strong teeth. But gender-specific probiotic benefits also exist. For instance, women who take probiotic supplements may be more likely to maintain vaginal and breast health, and expecting mothers who take probiotics can get support with some of the less pleasant side effects of pregnancy.
Like many of my patients, 33-year-old Dawn didn’t initially make the connection between irritable bowel syndrome (IBS), depression, and overall gut health. While we discussed her digestive problems during our initial consultation, she casually mentioned her primary care physician wanted to wean her off selective serotonin reuptake inhibitors (SSRIs). These antidepressant medications change your brain chemistry but also wreak havoc on your gut and impair nutrient digestion.
In addition, research going back to 2009, has shown that a mix of three strains of bacteria (Bifidobacterium bifidum, Bifidobacterium lactis, and Lactococcus lactis) given to babies who have a family history of allergic disease, can help prevent the likelihood of eczema. In this study, the probiotic was given to mothers during their pregnancy and to their babies during the first 12 months of life.

Sherman P.M., Johnson-Henry K.C., Yeung H.P., Ngo P.S., Goulet J., Tompkins T.A. (2005) Probiotics reduce enterohemorrhagic Escherichia coli O157:H7- and enteropathogenic E. coli O127:H6-induced changes in polarized T84 epithelial cell monolayers by reducing bacterial adhesion and cytoskeletal rearrangements Infect Immun 73: 5183–5188 [PMC free article] [PubMed] [Google Scholar]
Antibiotics are a common treatment for children, with 11% to 40% of antibiotic-treated children developing diarrhea.[13] Antibiotic-associated diarrhea (AAD) results from an imbalance in the colonic microbiota caused by antibiotic therapy.[13] These microbial community alterations result in changes in carbohydrate metabolism, with decreased short-chain fatty acid absorption and osmotic diarrhea as a result. A 2015 Cochrane review concluded that a protective effect of some probiotics existed for AAD in children.[13] In adults, some probiotics showed a beneficial role in reducing the occurrence of AAD and treating Clostridium difficile disease.[14]

“We know that there’s a symbiotic type of relationship between gut bacteria and their hosts—that’s us. Certain chemicals that the gut bacteria produce can alter blood pressure. We also know that when mice or rats or people have high blood pressure, the bacteria in their guts are different. Those things each reveal a piece of the puzzle. But we don’t have enough pieces to put the entire puzzle together yet,” says Pluznick.
Questions and concerns have been raised, however, about the safety of probiotic administration in the setting of a severe illness. Probiotic sepsis is the most feared complication related to probiotic administration [Boyle et al. 2006]. Lactobacillus is a rare but documented cause of endocarditis in adults [Cannon et al. 2005]. There are several reports in the literature of bacteremia in adults and children in the setting of probiotic administration [De Groote et al. 2005; Land et al. 2005; Kunz et al. 2004, 2005; Mackay et al. 1999; Rautio et al. 1999]. In addition, several cases of Saccharomyces boulardii fungemia have been reported in the literature [Cherifi et al. 2004; Henry et al. 2004; Cassone et al. 2003; Lestin et al. 2003; Riquelme et al. 2003; Lherm et al. 2002; Cesaro et al. 2000; Hennequin et al. 2000; Perapoch et al. 2000; Rijnders et al. 2000; Niault et al. 1999; Bassetti et al. 1998; Fredenucci et al. 1998; Pletincx et al. 1995], including two series in which the fungi spread to neighboring patients who were not taking the probiotic [Cassone et al. 2003; Perapoch et al. 2000]. This spread was thought to be due to contamination of central catheters in patients who had intestinal surgery (jejunostomy) or chronic illnesses (valvular heart disease), and who were immunocompromised. Only one case of probiotic sepsis was thought to have been directly fatal [Lestin et al. 2003]. A randomized, double-blind, placebo-controlled trial was performed using probiotic prophylaxis (six different strains of viable bacteria: L. acidophilus, L. casei, L. salivarius, L. lactis, B. bifidum, and B. lactis) in a total daily dose of 1010 bacteria orally twice daily for 28 days in patients hospitalized with severe acute pancreatitis. This showed no decrease in infectious complications but increased mortality (16%) in the probiotics group in comparison with the placebo group (6%, relative risk [RR] 2.53, 95% confidence interval [CI] 1.22–5.25). Nine of the 152 patients in the probiotics group developed bowel ischemia, eight of whom died, compared with none in the placebo group [Besselink et al. 2008].
Probiotics stick around for a while, though for how long isn’t precisely clear. You have to keep taking them to continue to reap the benefits. Further, getting a wide variety of strains into your system is beneficial. “Periodically mixing up your probiotic supplement is also a good way to ensure that you get different health-building strains in your health regime,” says Dr. Cook.
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.
The U.S. Clinical Guide to Probiotic Products1, Canadian Guide to Probiotic Supplements2 and the WGO Global Guidelines for Probiotics and Prebiotics3 provide suggested effective amounts of specific strains for treating certain health conditions, such as constipation or IBS. All 37 products listed the species of bacteria they contained, but only 14 listed amounts of individual strains. We found that 9 of those 14 products provided beneficial bacteria at effective levels. The Center for Responsible Nutrition recommends4 the industry move toward specifying strains as a best-practice because whether a product works and for what purpose depends on its strains.
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.
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