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For the generally healthy person, you can make a very good case to trust your own body to select and grow the best bacteria that are already in everyone. The foods you eat greatly influence your bacterial mix. Although probiotics offer many positive health benefits, there is no guarantee that they can make the trip from your mouth to your lower gut intact. Although adding more prebiotic fiber to your diet cannot guarantee safe passage of probiotics, it can influence the healthy bacteria that already live in your system. If probiotics help you, eating prebiotic foods or supplements will cause those healthy bacteria to flourish.
Even for healthy people, there are uncertainties about the safety of probiotics. Because many research studies on probiotics haven’t looked closely at safety, there isn’t enough information right now to answer some safety questions. Most of our knowledge about safety comes from studies of Lactobacillus and Bifidobacterium; less is known about other probiotics. Information on the long-term safety of probiotics is limited, and safety may differ from one type of probiotic to another. For example, even though a National Center for Complementary and Integrative Health (NCCIH)-funded study showed that a particular kind of Lactobacillus appears safe in healthy adults age 65 and older, this does not mean that all probiotics would necessarily be safe for people in this age group.
Cleaning up your diet to remove things that bother you and to add nutrients you and your microbiota need, physical activity to reduce stress and increase feel-good neurotransmitters, mindfulness to discover how your thoughts affect your feelings, and daily consumption of probiotic pills and foods are easy ways to improve your mental health outlook.
You may have heard that taking vitamin C or zinc is helpful, preventively or during sickness. This is because vitamin C and zinc improve the functioning of cells of your innate immunity, your first line of defense against pathogens like the flu. They also are involved in the generation of and protection against the inflammatory response caused by the battle with the flu.
Yes. Probiotics are incredibly important and effective. We know there are more bacteria in us and on us than our own human cells. The body is almost like a puppet—it is bacteria that really runs the show: They turn on enzymes, turn off genes, and dictate much of our health. We need them to break down nutrients, like copper and magnesium, so we can better absorb them. Interestingly, studies show that conditions like anxiety, depression, and weight gain can be transferred via fecal transplants (with mice), suggesting the broad impact bacteria has on health.

Here’s a quick timeline of the latest probiotic research that is setting off alarm bells for scientists around the globe: On June 19, a study was published linking probiotic use to brain fogginess and extreme belly bloating in some people. Another study, published on August 31, reported that consuming probiotics after taking antibiotics was linked to more severe intestinal infections in mice exposed to Cryptosporidium.  (For more see, "In a Brain Fog? Probiotics Could Be the Culprit" and "Unexpected Findings Cause Scientists to Rethink Probiotics.") 

Since the bulk of your natural flora exists in your gut, it makes sense that this is the part of your body that feels it most when bacteria become imbalanced. Women, in particular, can experience all kinds of digestive problems, particularly during hormone fluctuations. These are just some of the digestive symptoms a high-quality probiotic can help reduce and even treat:
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.
This high-potency (25 billion CFU) supplement blends 12 different strains in a base of inulin. The Ther-Biotic Complete capsules are vegetarian (made from hydroxypropyl methylcellulose, water) and the formula is free of common allergens, such as milk, eggs, fish, tree nuts, peanuts, wheat, gluten, and soy so it’s perfect for those with allergies. There are 60 capsules per bottle.
Unlike many of the probiotics on the market today for women, Vitamin Bounty’s formula is fermented naturally and encased in a delayed-release capsule for more efficient digestion. Specifically, this capsule helps to protect the micro-organism strains from stomach acid, which can dissolve them before your gut has a chance to absorb all of their healthy goodness. With this Women’s Pro-Daily Probiotic design, you can expect more cultures and, as a result, fewer stomach upsets and feminine health problems!
In the second study, the researchers questioned whether patients should be taking probiotics to counter the effects of antibiotics, as they are often told to do in order to repopulate the gut microbiota after it's cleared by antibiotic treatment. To look at this, 21 volunteers were given a course of antibiotics and then randomly assigned to one of three groups. The first was a "watch-and-wait" group that let their microbiome recover on its own. The second group was administered the same generic probiotics used in the first study. The third group was treated with an autologous fecal microbiome transplant (aFMT) made up of their own bacteria that had been collected before giving them the antibiotic.
"The proprietary formula in this lotion supports a healthy microbiome of your skin promoting a more hydrated, stronger barrier function and protection from pathogens without harming the good stuff. Throw away your antibacterial soap and hand sanitizer and use this all over after your shower and after washing your hands," says Astarita, who is also a fan of the Nerium Prolistic Powder Pre & Probiotic Plus Vitamins ($45) and Be Well Probiotic Powder ($46) by Dr. Frank Lipman.

Helicobacter pylori (H. pylori) is a bacteria that causes chronic inflammation (gastritis) of the inner lining of the stomach, and also is the most common cause of ulcers worldwide. About 50% of people in the world carries or is infected with H. pylori. Common symptoms of H. pylori infection are occasional abdominal discomfort, bloating, belching or burping, and nausea and vomiting. H. pylori infection is difficult to erdicate, and treatment is with two or more antibiotics.

Align uses the patented probiotic strain Bifidobacterium, which helps to maintain a healthy digestive system and digestive balance. It contains 1 billion CFUs when manufactured, and 10 million CFUs when used by the best by date. (Very often, the number of CFUs in a product decreases over time.) If you have trouble digesting certain foods such as caffeine or dairy, this will be a good option for you.
Our gut is home to over 500 bacterial species. These “visitors” form a bioreactor, which facilitates digestion, provides nutrients, and helps form the immune system. Some important nutrients made by this bioreactor include several B vitamins, vitamin K, folate, and some short-chain fatty acids. Up to 10% of an individual’s daily energy needs can be derived from the byproducts of the good bacteria in your gut.
We have to give a nod to the most famous probiotic food: yogurt. Whether you love Greek or regular, low-fat or full-fat, look for the phrase "live active cultures" on the label. And although choosing a plain yogurt has less added sugar than the flavored kinds, Tallmadge gives you the okay to choose a fruit-infused flavor if that's the only way you'll eat it. Just be sure to aim for fewer than 15 grams of the sweet stuff per serving; sugar can feed the bad bugs in your gut.
Dr. Michelle Schoffro Cook says there’s no single best strain of bacteria, though some strains, like L. Acidophilus or B. Bacterium, have wide-reaching effects. They often act as a starting point from which to add other strains with more specific impacts. Already have probiotics on hand or want to arm yourself with raw knowledge before you shop? The table below shows the research- and expert-backed strains we looked for in each use case:
It seems like one minute you have diarrhea (D) and the next minute you are constipated (C). Abdominal pain, cramping, and bloating come and go. You are tired of running to the bathroom frequently, or spending a long time in the bathroom waiting for something to happen. Irritable bowel syndrome (IBS) is a diagnosis of exclusion. Infections and other causes of your IBS-C dominant or IBS-D dominant symptoms have to be ruled out, but in many cases the diagnosis of IBS doesn’t really provide answers. You may be on a low FODMAP (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols) diet, which helps, but is restrictive.
While probiotics have been around as long as bacteria have, they were first officially identified for their health benefits in the early 20th century by Russian-born biologist Élie Metchnikoff. Metchnikoff believed that “good bacteria” like the microbes that produce lactic acid could prolong life and stave off senility, and actually recommended drinking sour milk daily for overall health. While Metchnikoff’s theories were pooh-poohed by many of his contemporaries, the first commercial probiotic, Yakult, hit the market in 1935 and is still on the shelves today.
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.)
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

The scientists discovered that the probiotics successfully colonized the GI tracts of some people, called the "persisters," while the gut microbiomes of "resisters" expelled them. Moreover, the persister and resister patterns would determine whether probiotics, in a given person, would impact their indigenous microbiome and human gene expression. The researchers could predict whether a person would be a persister or resister just by examining their baseline microbiome and gut gene expression profile.
Most people with diverticulosis have few if any symptoms at all. When people do experience signs and symptoms of diverticulosis (diverticular disease) they may include abdominal pain, abdominal cramps, diarrhea, constipation, and bloating. Diverticulitis is a condition in which diverticuli in the colon rupture. The rupture results in infection in the tissues that surround the colon. Treatment methods for diverticulitis includes prescription medications, and in some cases, diverticulitis surgery.
Animals, including humans, have microbes inside them that benefit them in multiple ways. These microbes are in a loose sense like probiotics, but the definition of probiotics was established to designate those microbes that have been isolated, studied, tested in a laboratory dish and/or clinically in animals and/ or humans, and proven to have beneficial properties. In many cases their genetic fingerprints were sequenced for identification purposes and also to check for potentially harmful genetic components. The official term “probiotics” established specific criteria for scientific studies and probiotic supplements, foods, and drinks.
Jotham Suez, Niv Zmora, Gili Zilberman-Schapira, Uria Mor, Mally Dori-Bachash, Stavros Bashiardes, Maya Zur, Dana Regev-Lehavi, Rotem Ben-Zeev Brik, Sara Federici, Max Horn, Yotam Cohen, Andreas E. Moor, David Zeevi, Tal Korem, Eran Kotler, Alon Harmelin, Shalev Itzkovitz, Nitsan Maharshak, Oren Shibolet, Meirav Pevsner-Fischer, Hagit Shapiro, Itai Sharon, Zamir Halpern, Eran Segal, Eran Elinav. "Post-Antibiotic Gut Mucosal Microbiome Reconstitution Is Impaired by Probiotics and Improved by Autologous FMT." Cell (First published: September 6, 2018)  DOI: 10.1016/j.cell.2018.08.047
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.
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.
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.
Large bodies of evidence suggest that probiotics are effective against several forms of diarrhea, including antibiotic-associated diarrhea, acute diarrhea, traveler’s diarrhea, infectious diarrhea and other associated diarrhea symptoms. They also help with constipation relief. Probiotics have also been found in meta-analyses to reduce the pain and severity of irritable bowel syndrome (IBS) symptoms, aid in the eradication of H. pylori and treat pouchitis, a condition that occurs after the surgical removal of the large intestine and rectum.
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.

Many studies have shown that probiotics reduce diarrhea associated with taking antibiotics in both adults and children. In fact, it is common for physicians and pharmacists to recommend eating a probiotic-fortified yogurt every day during a course of antibiotics to prevent diarrhea. More research is needed to determine which probiotics are associated with the greatest effect for specific antibiotics.


Until recently, testing of probiotics by ConsumerLab.com found that some products had far lower amounts of live organisms than claimed on the labels. But in 2018, it found that 17 out of 18 products tested contained the amounts listed; none exceeded limits for heavy metal contaminants. In contrast, in 2016, a study in Pediatric Research found that only one out of 16 Bifidobacterium longum supplements tested contained the species named on the label.
Probiotics are officially defined by the Joint Food and Agricultural Organization of the United Nations/World Health Organization Working Group as “Live microorganisms that, when administered in adequate amounts, confer a health benefit on the host.” Basically, probiotics at this point in time are live bacteria and yeasts that provide health benefits to you if you take them in adequate quantities.

That said, supplements with higher numbers of CFUs are sometimes used to treat conditions such as irritable bowel syndrome (IBS), allergies, and respiratory illness. While probiotics have generally been found to be safe for most people with normal immune systems, too much can cause gas and upset stomach. We narrowed our search to supplements with dosages between 1 billion and 100 billion CFUs.


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.


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.
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.
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.
"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."
​​​​​​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.*
Culturelle Probiotics, although very basic, is still a great probiotic supplement.  The results I got from trying it were positive– I felt pretty good throughout the entire trial period. Although this product only contains one strain of probiotic, the one they chose is a solid one.  The cell count is 10 billion, which is a good number for a daily probiotic.  Lastly, Culturelle doesn’t contain any frequently-irritating ingredients like milk, dairy or gluten.  Read the full review here… or click here to go buy it now!
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!
While Lebwohl isn't comfortable endorsing a specific brand publicly, he did say "a widely used brand in which the compound is bifidobacteria or lactobaccilus seems like a reasonable way to go in a patient who is eager to give this a try, but would be best done under the supervision of a healthcare professional.” He does advise looking for a supplement with between 1 billion and 10 billion colony-forming units, or CFUs.

Of course, your gut microbiome can only do this when it’s healthy and in balance, which is where probiotics come in. Since so many factors can deplete your beneficial bacteria—including everything from exposure to antibiotics in food or medication to spending too much time inside—supplementing with a premium probiotic is almost always necessary to maintain balance.

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.

Stability and organism types — Some probiotic strains need to be kept cold in order to preserve their potency. This applies to their production, transport, storage and sales. Others are shelf-stable and don’t require refrigeration. Unfortunately, most refrigerated probiotics never make it past the stomach because they aren’t stable. Instead, look for a shelf-stable product that contains soil-based organisms.
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