What are the gut microbiota and human microbiome? Microbes are commonly associated with disease, but there are millions inside the human body, and some provide distinct benefits. The microbiota and microbiome of the human body have been researched intensively in recent years. Find out about what we now know about them and what they mean for health. Read now
Some yogurts contain the aforementioned bacteria; however, because they are sensitive to oxygen, light, and dramatic temperature changes, make sure to look for yogurts with “live and active cultures.” Many commercial yogurts are heat-treated or pasteurized, resulting in the loss of these valuable cultures. Learn more about the smart way to shop for probiotics.

Many wondered whether probiotics could be therapeutic in other gastrointestinal disorders. Unfortunately, that doesn’t appear to be the case. Probiotics didn’t show a significant benefit for chronic diarrhea. Three reviews looked at how probiotics might improve Crohn’s disease, and none could find sufficient evidence to recommend their use. Four more reviews looked at ulcerative colitis, and similarly declared that we don’t have the data to show that they work. The same was true for the treatment of liver disease.


If you have an immune system problem or another serious health condition, you may have a greater chance of issues. Some reports have linked probiotics to serious infections and other side effects. The people most likely to have trouble are those with immune system problems, people who've had surgery, and others who are critically ill. Don't take probiotics if you have any of those issues.
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.
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.
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.
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.
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.”
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.
Among their numerous health benefits, research shows these friendly microorganisms help prevent bowel diseases, improve your immune system, reduce traveler’s diarrhea, help you maintain a healthy weight, heal various skin conditions, improve bloating and other uncomfortable GI symptoms, and even boost your mood, helping to reduce the effects of anxiety and depression.
"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."
Probiotics for allergies are fast becoming a preferred treatment method because they are understood to be much safer than traditional allergic rhinitis medication. A nasal spray for allergies is often a ‘go to’ treatment, for example, but allergy nose spray medications often contain corticosteroids, like Beclometasone dipropionate, which could affect bone metabolism, blood cells, and the pituitary gland.
When shopping for a probiotic, the first things to look at are CFUs count and probiotic strains. CFUs is the acronym for colony forming units, and is the measure of how many probiotic bacteria are capable of dividing to form colonies. In other words, the higher the CFUs, the higher the number of active, live good bacteria. Generally speaking, the higher the CFUs, the better, although there are exceptions.
Unless you know that your body is lacking in a particular type of probiotic, you should just look for broad-spectrum probiotics that contain a mix of different strains of bacteria, Warren says: "We have billions of bacteria in our gut, so by taking a supplement with a range of different strains, you will ensure you are not overdoing or missing one type." Keatley also stresses the importance of finding a supplement with a diversity of bacteria strains to keep overgrowth of any one strain in check. "Providing too much of an advantage to one strain of probiotic may push out another strain we didn't know was important until it's too late," she points out.
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].
You know antibiotics can help fight off bacterial infections, but overusing them can actually deplete the good bacteria in your body, reports Harvard Medical School. (That's why doctors recommend you don't take antibiotics unless you really need them.) If you must go on meds, talk with your doctor about taking probiotics afterward, as the NCCIH says they can help recover beneficial microorganisms afterward and help keep the ratio of good to bad bacteria in balance.
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.
Yes! Beneficial yeast is a probiotic, defined as a microorganism that supports human wellness. (Probiotic means “for life.”) Saccharomyces boulardii is a remarkable yeast that can significantly support your whole internal ecosystem. It helps reduce problematic yeasts, such as Candida, and replenishes healthy gut flora.* While many probiotic supplements only deliver friendly bacteria without yeast, Probiotic All-Flora contains 5 billion CFU of beneficial yeast for complete support.
Yeast Infections and Bacterial Vaginosis (BV) – If you’ve ever experienced the discomfort of a yeast infection or BV, then you are probably aware that an overgrowth of bacteria causes these unfortunate episodes. While your reproductive system is supposed to foster a healthy environment for yeast, sometimes these levels can increase causing the pain and discomfort of a yeast infection or bacterial infection. By taking a probiotic that contains prebiotics and feminine health probiotics, you can treat and prevent recurrent symptoms!
The above line of probiotics is also a favorite of Engelman. "I like Nerium International's new Prolistic Pre & Probiotic Plus Vitamins ($45) because it combines prebiotics, probiotics, and vitamins," Engelman explains. "It supports overall health while targeting digestive function. It contains two types of prebiotics and two strains of probiotics to help enhance levels of beneficial microflora and balance levels of healthy bacteria in the digestive system. Additionally, it contains B vitamins, vitamin C, and vitamin D, which work to enhance the body's immune system and support natural energy production."
Taking a probiotic every day is a good way to help prevent getting sick and having to go on antibiotics in the first place. Preventative measures, of course, are preferred. Another that is believed to help is upping your vitamin D intake when your immune system needs a boost. Diet is also huge in terms of preventing sickness. Studies show that you can change your microbiome within hours of adjusting your diet. If you’re not into sauerkraut, even just cutting back on sugar and eating more whole foods can make a difference.
Dr. Vincent M. Pedre, medical director of Pedre Integrative Health and president of Dr. Pedre Wellness, is a board-certified internist in private practice in New York City since 2004. His philosophy and practices are a blend of both Western and Eastern medical traditions. He is a clinical instructor in medicine at the Mount Sinai School of Medicine and is certified in yoga and medical acupuncture. His unique methodology is best described as integrative or defined by a functional, systems-based approach to health. With his holistic understanding of both sides of the equation, he can help each patient choose the best course of action for their ailments to provide both immediate and long-term relief. His holistic approach incorporates positive, preventive health and wellness lifestyle choices. Dr. Pedre Wellness is a growing wellness platform offering health-enhancing programs along with informative social media and lifestyle products, such as dietary supplements, books, and weight-loss programs.
Kefir: This could be the most ideal probiotic dairy product because it contains both bacteria and yeast working together to provide the numerous health benefits. In a recent eight-week study, people with diabetes were given kefir milk containing Lactobacillus casei, Lactobacillus acidophilus, and bifidobacteria vs. conventional fermented milk. The hemoglobin A1C levels were significantly lower in the group consuming the kefir.
We are clearly getting to the strain level by going beyond “Saccharomyces boulardii” and to “Saccharomyces boulardii CNCM I-745”. They did a great job by actually putting it on the label so you don’t even have to contact the company to see exactly what strain you’re getting. (P.S. this is a well-researched strain that I highly recommend, especially for preventing antibiotic-associated diarrhea.)
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.
Every person's microbiome is different, which means what worked for others might not work for you. "What you eat, whether you were born by C-section or vaginally, what antibiotics you have been exposed to, and whether or not you have ever developed food-borne illness are just some of the many factors that impact your gut microbiome," explains Scarlata. And while research can help you determine which strains to take at which dosages, there may still be several different formulations to choose from.

The research also showed that while probiotics colonised the gastrointestinal tract of some people, the gut microbiome of others just expelled them. There was no way of telling from their stool sample which category people fell into. “Some people accept probiotics in their gut, while others just pass them from one end to the other,” says Elinav. They found that the probiotic colonisation patterns were highly dependent on the individual. That tells us that the concept that everyone can benefit from a universal probiotic bought from the supermarket is empirically wrong, he says.
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.
"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."
However, a 2003 pilot study and 2011 randomized, controlled trial both reported that RA activities remained unchanged, but the subjects treated with probiotics reported statistically significantly higher levels of “subjective well-being.” One suggested reason for this was that the trials were too short to establish changes in the observable changes in the internal earmarks of RA.
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.
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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.

The term "prebiotics" is often thrown around when probiotics are mentioned, and they're related to probiotics in a sense. According to Angelone, prebiotics are complex sugars that we don't digest but that are used as fuel by bacteria — including probiotics — that's already in your gut. Registered dietitian-nutritionist Beth Warren, founder of Beth Warren Nutrition and author of Living a Real Life with Real Food, explains that you can think of prebiotics as food for probiotics. You can get prebiotics from foods including asparagus, bananas, garlic, and onions, she says.

Very few women know that one of the leading causes of infertility, difficulties getting pregnant, and even painful periods stem from thyroid dysfunction. That’s why infertility specialists, obstetricians, and gynecologists alike often order thyroid testing at the first sign of trouble. Poor thyroid function is also linked to joint pain, unplanned weight-loss or obesity and heart problems and thinning skin among many other signs and symptoms.


Today, most of the Japanese population begins the day with a warm bowl of miso soup, believed to stimulate the digestive system and energize the body. Made from fermented soybeans, rice or barley, adding a tablespoon of miso to some hot water makes an excellent, quick, probiotic-rich soup. The fermentation process can take anywhere from a few days to a couple of years to complete, and the end result is a red, white or dark brown paste with a buttery texture. 

Certain brands, like Attune (attunefoods.com; available at Whole Foods), have pumped up the dessert by adding probiotics. (Attune boasts 6.1 billion CFUs, or "colony forming units," a measure of live, active microorganisms per serving. As a comparison, some probiotic supplements may contain 1 to 50+ billion CFUs.) Sounds crazy, but it's backed by science. One study in the International Journal of Food Microbiology found that probiotics added to chocolate were able to reach the GI tract where they could get to work colonizing the gut with healthy bacteria.
Possibly the most popular probiotic food is live cultured yogurt or greek yogurt made from the milk of cows, goats or sheep. Yogurt, in most cases, can rank at the top of probiotic foods if it comes from raw, grass-fed animals. The problem is there is a large variation on the quality of yogurts on the market today. When buying yogurt, look for three things: First, that it comes from goat’s, sheep milk or A2 cows milk; second, that it’s grass-fed; and third, that it’s organic.
Probiotics are bacteria that help keep the natural balance of organisms (microflora) in the intestines. The normal human digestive tract contains about 400 types of probiotic bacteria that reduce the growth of harmful bacteria and promote a healthy digestive system. The largest group of probiotic bacteria in the intestine is lactic acid bacteria, of which Lactobacillus acidophilus, found in yogurt with live cultures, is the best known. Yeast is also a probiotic substance. Probiotics are also available as natural health products.

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.
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.

This mildly sour, chewy bread is made with a lactic acid starter that contains strains of lactobacillus, a friendly type of bacteria that adds good microbes into the bakery staple. Sourdough may be the healthiest bread choice if diabetes is a concern for you: one 2008 study found that people with pre-diabetes who ate sourdough bread had less of a blood sugar spike compared to when they ate bread made with baker's yeast. (Experts also say fiber-rich whole grain bread can also reduce a post-meal blood sugar spike.) The researchers credit the lactic acid for the favorable effect.
If these issues and many others are connected to gut health, then what elements are essential for digestive health? Consider this: According to the National Institute of Diabetes and Digestive and Kidney Diseases, upward of 60 million to 70 million Americans are affected by digestive diseases. In addition, digestive disease and disorders cost the United States over $100 billion per year.
Probiotic therapy may also help people with Crohn's disease and irritable bowel syndrome. Clinical trial results are mixed, but several small studies suggest that certain probiotics may help maintain remission of ulcerative colitis and prevent relapse of Crohn's disease and the recurrence of pouchitis (a complication of surgery to treat ulcerative colitis). Because these disorders are so frustrating to treat, many people are giving probiotics a try before all the evidence is in for the particular strains they're using. More research is needed to find out which strains work best for what conditions. 
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