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.
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.
Previous studies have been contradictory, with some yielding more positive results about the benefits of probiotics, but most of them looked at probiotics in stool samples, not directly in the gut itself. In the new research, the scientists used more invasive methods to take samples of gut bacteria directly from different areas of the digestive system.

Then, study participants were divided into one group that consumed a standard probiotic strain available in commercial supplements and a control group that was given a placebo. After two months of treatment, the researchers found that some people were so-called “resisters” who expelled the gut microbiomes in probiotics; others were identified as “persisters” who successfully colonized the generic probiotic strains in their GI tracts.

Consuming probiotics regularly will reduce the risk of this. "The concept is that if we have an unhealthy, unbalanced gut environment, toxins can be released into the bloodstream and cause inflammation throughout the body," Engelman adds. "This shift in gut flora and the subsequent inflammation can cause a flare-up in the skin of those who are predisposed to acne, eczema, or rosacea."


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.
Taking relatively high doses of these probiotic strains before, during, and after antibiotic treatment can help your microbiome get back on its feet: B. Lactis, B. Infantis, L. Acidophilus, L. Casei, L. Bulgaricus, L. Paracasei, L. Rhamnosus GG, and S. Boulardii. Our antibiotic combatant MegaFood MegaFlora has six of these strains, as well as eight others. One serving contains 20 billion CFUs to replenish the good bacteria.

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.
In addition to the impact on our immune systems, our digestive systems are the second largest part of the neurological system. It’s called the enteric nervous system and is located in the gut. This is why it’s called the second brain — the gut is responsible for creating 95 percent of the serotonin and may have significant impact on brain function and mood.

If your child has a history of stomach problems that medicine doesn’t seem to help, adding a probiotic to his or her diet can help. We love the OLLY Kids Happy Tummy Gummy Supplements because they offer complete probiotic support in a kid-friendly gummy form. Each gummy has a blend of prebiotic, probiotic, and peppermint to help soothe upset stomachs. They contain 500 million CFU of Bacillus coagulans. This container comes with 30 gummies (to be taken once a day) and is recommended for children 2 years and older.
Probiotics: Health benefits, facts, and research Every human on the planet has microbes living in their body. While bacteria get a bad reputation, many can promote good health. Probiotics are a type of 'good bacteria' that provide health benefits for the host. The health benefits of probiotics include treatment of diarrhea and irritable bowel syndrome. Read now

A 2017 survey of cancer patients showed that more than 80 percent were taking some sort of dietary supplement, vitamin, mineral, or herb to treat digestive issues they were experiencing due to chemotherapy. Researchers noted that while supplements can be beneficial in some cases, they can also change the metabolism of anti-cancer drugs, or lead to life-threatening conditions like sepsis because of the patient’s compromised immune system.
Myriad factors – antibiotics, diet, stress, and age, among them – affect the balance of diverse microbes present in your gut. While you can replenish your gut bacteria by eating well and incorporating natural probiotics (ex. yogurt and kefir) into a healthy diet, these processes can take weeks or months; taking a regular probiotic is an easy and effective way to ensure your gut (and immune system) stays healthy, always.
Consuming probiotics regularly will reduce the risk of this. "The concept is that if we have an unhealthy, unbalanced gut environment, toxins can be released into the bloodstream and cause inflammation throughout the body," Engelman adds. "This shift in gut flora and the subsequent inflammation can cause a flare-up in the skin of those who are predisposed to acne, eczema, or rosacea."
If this ratio gets out of balance, the condition is known as dysbiosis, which means there’s an imbalance of too much of a certain type of fungus, yeast or bacteria that affects the body in a negative way. By consuming certain types of probiotics foods and dietary supplements (often in capsule form), you can help bring these ratios back into balance.
There are both probiotics and prebiotics in fermented foods. I differ from a lot of doctors in that I recommend that patients with infections like Candida and SIBO don’t eat prebiotics until they’ve cleared up the infection—because the prebiotics can feed those infections, too. I find that it’s better to get rid of those infections first, and then add in prebiotics to your diet after. [See here for more from Dr. Myers on treating yeast infections.]
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.
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.
If you don’t have a specific health goal in mind and want to bolster the number of good bacteria floating around your system, Perlmutter recommends starting with a minimum of eight to 10 different bacterial species. He included a core five (L. Plantarum, L. Acidophilus, L. Brevis, B. Lactis, and B. Longum) and we added five more highly researched and universally beneficial strains for a general health pick. Vita Miracle, formerly Islands Miracle, has nine of those 10, plus 30 billion CFUs per serving.
Flu is short for influenza, an upper respiratory viral infection. The main problem for you, and the main advantage for the survival of influenza viruses, is that there are many variations that can cause illness. Flu shots are based on virus strains that are anticipated to be widespread. Sometimes those assumptions are correct and other times they are not. This section will show you one overlooked way to fortify your body to best avoid becoming sick with the flu at all, or how to recover if you do succumb.
There is one Voluntary Certification Program by which a supplement manufacturer can choose to be evaluated. ConsumerLab.com (CL) is the leading provider of independent test results and information to help consumers and health-care professionals identify the best quality health and nutrition products. Products that have passed their testing for identity, strength, purity, and disintegration can print the CL Seal of Approval on their product. This is one step toward being confident that one is getting the amount and type of probiotic promised by the manufacturer.
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.
Probiotics are found in everything from chocolate and pickles to hand lotion and baby formula, and millions of people buy probiotic supplements to boost digestive health. But new research suggests they might not be as effective as we think. Through a series of experiments looking inside the human gut, researchers show that many people's digestive tracts prevent standard probiotics from successfully colonizing them. Furthermore, taking probiotics to counterbalance antibiotics could delay the return of normal gut bacteria and gut gene expression to their naïve state. The research publishes as two back-to-back papers on September 6 in the journal Cell.

Eating more foods that are naturally rich in probiotics, like yogurt, kimchi and kefir, can help restore balance in your gut and create more “good” bacteria to fight off inflammation from “bad” bacteria. But what about food products that have probiotics infused into them? Indeed, manufacturers are banking on a new crop of gut-friendly products. From chocolates and granola bars to juices and tonics, nut butters, bottled water and even air sprays, you can’t escape the probiotic movement.
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.

Undaunted, researchers looked into whether probiotics might be beneficial in a host of disorders, even when the connection to gut health and the microbiome was tenuous. Reviews show that there is insufficient evidence to recommend their use to treat or prevent eczema, preterm labor, gestational diabetes, bacterial vaginosis, allergic diseases or urinary tract infections.

What about prebiotics vs probiotics? Prebiotics are the food fibers that go through the gut unchanged and are then used by good colon bacteria as a food source for their own growth. Everyone already has most of these good bacteria present, but often in small quantities. Prebiotics are used to stimulate their growth. Simply stated, you already grow your own probiotics within your colon. You do not rely on them to make the passage through the stomach acid — acid that can destroy many probiotic bacteria. That’s why taking a probiotic supplement or adding probiotic foods to your diet does not always help your digestive system. You can eat as many probiotic bacteria as you want, but if they don’t survive the trip to the colon, your effort will be fruitless.
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If you’re most interested in taking a probiotic supplement for overall gut health, I suggest starting with 30 to 50 billion CFUs. Take probiotics on an empty stomach once or twice a day for at least three months. After that time, reassess and decide if the benefits warrant continuing a maintenance dose of the probiotic supplement. However, if you have SIBO, beware of starting a probiotic too soon after your treatment. In this case, it’s best to work with a health practitioner on which probiotic is right for each stage of the treatment.
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.
Made from aged, fermented soybeans, this paste is brimming with probiotics. You can buy miso paste in a bunch of varieties (white, yellow, red, brown) and the darker the color, the deeper the taste. Miso is a great way to add a burst of earthy, savory flavor for few calories (only 25 to 30 per tablespoon), plus protein, fiber, and bone-strengthening vitamin K, says Sharon Palmer, RDN, author of Plant-Powered for Life. "While we need more research about how these types of fermented foods contribute to health, it's a good idea to introduce more of them into your diet," she says. Use miso to glaze fish or chicken before cooking, mix into a stir-fry recipe, or add to liquid to make a miso broth. One caveat: Miso is very high in sodium. One teaspoon, enough to make a cup of miso soup, has 473 mg of sodium, 21% of the daily recommended limit and 32% of the daily limit for those with high blood pressure.

Using probiotics benefits and balances immune function, influences hormone levels, aids in digestion and nutrient absorption, produces some vitamins, and balances blood sugar insulin responses. By preventing and reducing leaky gut and controlling levels of pathogens, probiotics reduce harmful bacterial by-products that can enter the brain and contribute to brain fog.
Depression often goes hand in hand with anxiety. Both conditions can have origins in the gastrointestinal (GI) tract, which typical antidepressants and benzodiazepine medications do not address. Since there is a connection between the health of the GI tract and the health of the nervous system/brain, directly through the vagus nerve and also via indirect chemical effects, improving the former can positively affect the latter.
Quick note about some formulations with multiple strains (including this one): Take a look at the label below and you’ll see that the supplement contains a mix of strains, but the label just says there is a total of 20 billion CFUs (how they measure the amount of bacteria). This does not tell us how much of each particular strain there is, and we want to know that there are at least 1 billion CFUs per strain to get a beneficial effect.

While one 2009 study did show some evidence for reducing cold and flu symptoms in children ages three to five and a 2015 analysis showed probiotics to be better than placebo in preventing acute upper respiratory infections, neither were enough to convince the National Institutes of Health of the efficacy of probiotics for colds and flu. The NIH confirms, “the evidence is weak and the results have limitations.”


The idea that bacteria are beneficial can be tough to understand. We take antibiotics to kill harmful bacterial infections and use antibacterial soaps and lotions more than ever. The wrong bacteria in the wrong place can cause problems, but the right bacteria in the right place can have benefits. This is where probiotics come in. Probiotics are live microorganisms that may be able to help prevent and treat some illnesses. Promoting a healthy digestive tract and a healthy immune system are their most widely studied benefits at this time. These are also commonly known as friendly, good, or healthy bacteria. Probiotics can be supplied through foods, beverages, and dietary supplements.
The takeaway: Certain strains were found useful in preventing diarrhea among children being prescribed antibiotics. A 2013 review showed that after antibiotic use, probiotics help prevent Clostridium difficile-associated diarrhea. A review focused on acute infectious diarrhea found a benefit, again for certain strains of bacteria at controlled doses. There’s also evidence that they may help prevent necrotizing enterocolitis (a serious gastrointestinal condition) and death in preterm infants.
Probiotics help tip the balance back in favor of the good bacteria. In doing so, they may provide some relief if you have irritable bowel syndrome (IBS), ulcerative colitis, acute infectious diarrhea, and diarrhea associated with antibiotic use or Clostridium difficile (C.diff) infection. They also can boost your immunity, fight inflammation and potentially have beneficial effects on cholesterol.
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.
Even if some of the bacteria in a probiotic managed to survive and propagate in the intestine, there would likely be far too few of them to dramatically alter the overall composition of one's internal ecosystem. Whereas the human gut contains tens of trillions of bacteria, there are only between 100 million and a few hundred billion bacteria in a typical serving of yogurt or a microbe-filled pill. Last year a team of scientists at the University of Copenhagen published a review of seven randomized, placebo-controlled trials (the most scientifically rigorous types of studies researchers know how to conduct) investigating whether probiotic supplements—including biscuits, milk-based drinks and capsules—change the diversity of bacteria in fecal samples. Only one study—of 34 healthy volunteers—found a statistically significant change, and there was no indication that it provided a clinical benefit. “A probiotic is still just a drop in a bucket,” says Shira Doron, an infectious disease expert at Tufts Medical Center. “The gut always has orders of magnitude more microbes.”
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.∗
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