Even with antibiotic-associated diarrhea, which has the best evidence, "you could have seven people take the same probiotic and only have one report a definite difference," says gastroenterologist Matthew Ciorba, M.D., a medical professor who studies human gut microbiota at Washington University School of Medicine in St. Louis. That's because each person's microbial makeup is as unique as a fingerprint, influenced by age, genetics, and gender. For example, animal research from the University of Texas at Austin found the microbes living in the guts of males and females react differently to the same diet. Scientists are now studying ways to harness a person's own microbes to treat illnesses, rather than going for a mass approach.
Secondly, probiotics must have undergone controlled evaluation to document health benefits in the target host. Only products that contain live organisms shown in reproducible human studies to confer a health benefit can actually claim to be probiotic.[3][115][116] The correct definition of health benefit, backed with solid scientific evidence, is a strong element for the proper identification and assessment of the effect of a probiotic. This aspect represents a major challenge for scientific and industrial investigations because several difficulties arise, such as variability in the site for probiotic use (oral, vaginal, intestinal) and mode of application.[61] 

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.
Infectious diarrhea in both adults and children may be shortened by the use of probiotics [Allen et al. 2004]. The duration of symptoms is decreased by about 30 hours as suggested by a systematic review of trials in active infectious diarrhea. In this Cochrane review, 23 studies including almost 2000 participants (352 of which were adults), it was concluded that probiotics reduced the risk of persistent diarrhea compared with placebo or no probiotics at 3 days with a RR of 0.66 (95% CI 0.55–0.77) [Allen et al. 2004]. The majority (18 out of 23 studies) of the probiotics tested were LABs with two studies using S. boulardii.
All probiotic strains are manufactured through fermentation, and are then freeze-dried before blending with fructooligosaccharides (FOS). The result is a shelf-stable (two years at room temperature), nitrogen-filled probiotic of human origin: a probiotic that easily adapts to your body, and is both acid- and bile-resistant to survive the acidic environment of the human stomach. In other words, a probiotic that fulfills its promises.
While past studies have investigated similar questions, they have all used patients' excrement as a proxy for microbe activity in the GI tract. Instead, Elinav, his colleague Eran Segal, (a computational biologist at the Weizmann Institute), and their teams spearheaded by Niv Zmora, Jotham Suez, Gili Zilberman Schapira, and Uria Mor of the Elinav lab collaborated with Zamir Halpern, Chief of Gastroenterology at the Tel Aviv Medical Center to measure gut colonization directly.
The discovery of the benefits of probiotics began with sour milk. Today we have many other options to get various bacteria from our foods, although it's not as simple as just adding them to the food. For there to be health benefits, the microorganism has to be able to survive the passage through the gastrointestinal tract, survive the food manufacturing process, and grow and survive during the ripening or storage period. Also, the bacteria must not negatively affect product quality and be included on the Generally Recognized as Safe (GRAS) list.
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.”
Naturally fermented pickles, the type in which vinegar is not used in the pickling process, are rich sources of good bacteria. Sea salt and water are used in a fermentation process that results in the growth of good bacteria. Make sure vinegar was not used in the pickling process as pickles made in this way will not be rich in bacteria that boosts healthy gut flora. Beneficial bugs in fermented foods like pickles boost gut health and encourage a diverse microbiome. Eating foods that are rich in probiotic bacteria such as pickles retards the growth of harmful bacteria and it boosts the body's defenses against infection.
It’s not just about vanity! Your skin is your largest organ, and it protects your body from countless external threats. But, what many people don’t realize is that your skin is an important reflection of your internal health. Skin problems can result from nutritional and hormonal imbalances, as well as immune system disruptions, all issues that begin in the gut.

^ Wu, G. D.; Chen, J.; Hoffmann, C.; Bittinger, K.; Chen, Y.-Y.; Keilbaugh, S. A.; Bewtra, M.; Knights, D.; Walters, W. A.; Knight, R.; Sinha, R.; Gilroy, E.; Gupta, K.; Baldassano, R.; Nessel, L.; Li, H.; Bushman, F. D.; Lewis, J. D. (2011). "Linking Long-Term Dietary Patterns with Gut Microbial Enterotypes". Science. 334 (6052): 105–8. Bibcode:2011Sci...334..105W. doi:10.1126/science.1208344. PMC 3368382. PMID 21885731.


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.


If you want to get to the root causes of what goes on inside your gut, look at what you’re putting at the end of your fork. If you consume a milkshake, hamburger, and French fries, you turn on genes that promote inflammation in your gut and your body. On the other hand, if you eat 2 cups of steamed broccoli, you will turn on anticancer and anti-inflammatory gene pathways. The foods you eat control your state of health, and the gut is the gateway to the rest of the body. Identifying and eliminating foods that rob your body of energy becomes a central focus in my program. Gluten, eggs, dairy, soy, most legumes, corn, and sugar (and, for some of you, nightshades) are inflammatory and make you and your gut sick. When my patients eliminate these problem foods for at least 28 days, they feel better, lose weight, and heal their gut.
Walk into any grocery store, and you will likely find more than a few “probiotic” products brimming with so-called beneficial bacteria that are supposed to treat everything from constipation to obesity to depression. In addition to foods traditionally prepared with live bacterial cultures (such as yogurt and other fermented dairy products), consumers can now purchase probiotic capsules and pills, fruit juices, cereals, sausages, cookies, candy, granola bars and pet food. Indeed, the popularity of probiotics has grown so much in recent years that manufacturers have even added the microorganisms to cosmetics and mattresses.

Rachel Allen is a writer at Hyperbiotics who's absolutely obsessed with learning about how our bodies work. She's fascinated by the latest research on bacteria and the role they play in health, and loves to help others learn about how probiotics can help the body get back in balance. For more ideas on how you can benefit from the power of probiotics and live healthier days, be sure to subscribe to our newsletter. To learn more about how a healthy microbiome can enrich your life, subscribe to our newsletter.


“I recommend this to my patients because Metagenics provides high-quality, professional-grade supplements that are scientifically formulated,” says Crystal Karges, MS, RDN, a maternal health dietitian in San Diego. “Supplementing with the specific probiotic strains in this product can help maintain healthy vaginal microflora and support urogenital health. Recent research has found that consuming probiotics during pregnancy may reduce the chances of premature birth and preeclampsia in late pregnancy.”

If you want to try supplements, he suggests taking them daily for at least three months and keeping a journal to see if you notice any improvements. If you won’t remember to take them daily, however, don’t even bother. Because the strains of bacteria in supplements are not the same ones already living in your gut, it takes a few days for them to populate and build up in your gut, and then you must continue to deliver them via supplements to maintain any activity.

Drinking milk that has been fermented with acidophilus, or acidophilus milk, is a great way to get more probiotics in your diet. Buttermilk is similarly cultured with lactic acid bacteria (LAB) and is a good source of probiotics. These probiotics may help guard against various infections, cancer, and high blood pressure. They may also help improve cognitive function, boost immunity, and fight allergies. Acidophilus milk and buttermilk are available in many grocery stores. Lactobacillus reuteri is one beneficial probiotic in milk that may help combat diarrhea.


Bacteria die out over time. Some supplements list the potency when they were manufactured (before they rode in a truck, sat on the shelf at the grocery store, or hung out in the kitchen cupboard for a few months). In this case, there could be dramatically fewer viable bacteria by the time you consume them than when they were first encapsulated, and good bacteria are no good to you dead.


This content is strictly the opinion of Dr. Josh Axe and is for informational and educational purposes only. It is not intended to provide medical advice or to take the place of medical advice or treatment from a personal physician. All readers/viewers of this content are advised to consult their doctors or qualified health professionals regarding specific health questions. Neither Dr. Axe nor the publisher of this content takes responsibility for possible health consequences of any person or persons reading or following the information in this educational content. All viewers of this content, especially those taking prescription or over-the-counter medications, should consult their physicians before beginning any nutrition, supplement or lifestyle program.

Some probiotics are suggested as a possible treatment for various forms of gastroenteritis,[91] and a Cochrane Collaboration meta-analysis on the use of probiotics to treat acute infectious diarrhea based on a comprehensive review of medical literature through 2010 (35 relevant studies, >4500 participants) reported that use of any of the various tested probiotic formulations appeared to reduce the duration of diarrhea by a mean of 25 hours (vs. control groups, 95% confidence interval, 16–34 hours), also noting, however, that "the differences between the studies may be related to other unmeasured and unexplored environmental and host factors" and that further research was needed to confirm reported benefits.[92][93]

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.
However, it’s not just digestive woes that probiotics can help address. A clinical case series followed 300 patients who took a probiotic mixture of L. acidophilus and L. bulgaricus. They documented that 80% of acne patients had some degree of clinical improvement, particularly effective in inflammatory acne. Later, an Italian study involving 40 patients found L. acidophilus and B. bifidum supplementation produced better clinical outcomes in acne as well as better tolerance and compliance with antibiotics [2]. 

Because of the way that beneficial probiotic bacteria affects the digestive system, some researchers speculate that taking probiotic supplements could help to address symptoms of certain medical conditions. A clinical review published in "Canadian Family Physician" concluded that there was promising evidence that probiotics could be beneficial for people with a digestive disease called inflammatory colitis. They may also help to improve symptoms of vaginal infections. However, the review stated that more research was needed to prove the benefits of good bacteria for these conditions. Research is also investigating the possible benefits for those with irritable bowel syndrome. Some scientists also speculate that probiotics could be beneficial for travel-related diarrhea and other types of stomach upset. These proposed uses are currently under investigation.
Important Disclaimer: The information contained on Health Ambition is intended for informational and educational purposes only. Any statements made on this website have not been evaluated by the FDA and any information or products discussed are not intended to diagnose, cure, treat or prevent any disease or illness. Please consult a healthcare practitioner before making changes to your diet or taking supplements that may interfere with medications.

In 1920, Rettger and Cheplin reported that Metchnikoff's "Bulgarian Bacillus", later called Lactobacillus delbrueckii subsp. bulgaricus, could not live in the human intestine.[59] They conducted experiments involving rats and humans volunteers, feeding them with Lactobacillus acidophilus. They observed changes in composition of fecal microbiota, which they described as "transformation of the intestinal flora".[59] Rettger further explored the possibilities of L. acidophilus, and reasoned that bacteria originating from the gut were more likely to produce the desired effect in this environment. In 1935 certain strains of L. acidophilus were found very active when implanted in the human digestive tract.[60] Trials were carried out using this organism, and encouraging results were obtained, especially in the relief of chronic constipation.[citation needed]
A popular dish in Japan consisting of fermented soybeans, natto contains the extremely powerful probiotic bacillus subtilis, which has been proven to bolster your immune system, support cardiovascular health and enhance digestion of vitamin K2. Natto can also contain vitamin B12, which is usually lacking in vegan diets. It’s also one of the highest plant-based proteins.
Probiotics have been shown to improve symptoms in IBS, traveller’s diarrhoea and the duration of antibiotic associated diarrhoea. There is emerging evidence that probiotics may improve cholesterol levels in people with type II diabetes, and could play a role in benefitting cold or flu outcomes during stressful periods. However, these are very small studies and more research is needed before robust recommendations can be made. 

“Bifidobacterium is a type of probiotic well known for its antibacterial abilities and vaginal health help,” says Kristin Gustashaw, MS, RDN, an advanced clinical dietitian at Rush University Medical Center in Chicago. “Like Lactobacillus, it helps boost your immune system. It also improves the absorption of iron, calcium, magnesium, and zinc. Align is a good supplement that contains Bifidobacterium.” As an added bonus, it may even enhance your mood; Bifidobacterium makes the list of the best supplements for depression.

Studies have shown some benefits linked to Lactobacillus and treating and/or preventing yeast infections, bacterial vaginosis, urinary tract infection, irritable bowel syndrome, antibiotic-related diarrhea, traveler's diarrhea, diarrhea resulting from Clostridium difficile, treating lactose intolerance, skin disorders (fever blisters, eczema, acne, and canker sores), and prevention of respiratory infections.
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.
Diversity of strains - research has demonstrated that bacteria prefer to colonize in different parts of your digestive tract, where there are various ecological niches. The more probiotic strains you ingest, the more coverage you’ll provide for each of these niches. Each strain of bacteria also has its own different purpose, so choosing a formula with many different strains gives you that many more benefits.
Non-dairy sources of probiotics include miso, tempeh, kimchi, and sauerkraut. Miso is a savory, nutty paste made from fermented soybeans. It's extremely versatile and a lovely addition to soups, marinades, vegetables, and dressings, like this Miso Citrus Vinaigrette. If you're not familiar with tempeh (aka tofu's counterpart), it is comprised of fermented soybeans that are packed into cakes. Tempeh makes a great alternative to meat in sandwiches, stir-fries, and curries.
Here they perform a dual role: firstly, a probiotic supplement can ensure that the gut flora remains healthy and well-balanced. This could speed up the return to normal defecation. Secondly, serious diarrhoea can cause the gut flora to become depleted, which can slow recovery. In some cases, symptoms may even worsen. Once again, probiotic supplements can help you to regain a healthy balance of intestinal bacteria.
Having a healthy gut flora means an abundance for your health, digestion, well-being, and even beauty! As we saw last week, there’s ongoing communication between your GI and your brain, known as the gut brain axis. This means a healthy gut can benefit the regularity of your digestion as well as cognitive function like mood and depression, and even the health and appearance of your skin.

Rachel Allen is a writer at Hyperbiotics who's absolutely obsessed with learning about how our bodies work. She's fascinated by the latest research on bacteria and the role they play in health, and loves to help others learn about how probiotics can help the body get back in balance. For more ideas on how you can benefit from the power of probiotics and live healthier days, be sure to subscribe to our newsletter. To learn more about how a healthy microbiome can enrich your life, subscribe to our newsletter.
Some strains of lactic acid bacteria (LAB) may affect pathogens by means of competitive inhibition (i.e., by competing for growth) and some evidence suggests they may improve immune function by increasing the number of IgA-producing plasma cells and increasing or improving phagocytosis, as well as increasing the proportion of T lymphocytes and natural killer cells.[96][97] LAB products might aid in the treatment of acute diarrhea, and possibly affect rotavirus infections in children and travelers' diarrhea in adults,[96][97] but no products are approved for such indications. A large study demonstrated that probiotics may decrease dental caries in children.[98] Two reviews reported reduction of the incidence of respiratory-tract infections in adults.[99][100]
"Want to feel happier, get off SSRIs? You have to mind your gut," I told Dawn before explaining the often-overlooked gut-brain connection. It isn’t just depression that gut health affects but headaches, migraines, allergies, autoimmunity, weight gain, acne, skin rashes, yeast infections, hormonal imbalances, fatigue, immune challenges, and even the way you sense pain can be linked to your gut health. So as a medical doctor who specializes in gut health, when I say things start in your gut—I really mean it!

Amy Shapiro, MS, RD, CDN, founder and director of Real Nutrition based in NYC, discusses the effect probiotics have on immune system issues. "Probiotics compete with pathogenic microorganisms and produce chemicals that inactivate or kill pathogens," says Shapiro. "They help prevent immune-mediated diseases by improving the gut mucosal immune system. Overall, probiotics protect the body from infections and allow the body to maintain homeostasis."


BlueBiotics is a good product to start with and then evaluate from there. The cold is actually good for probiotics as freezing them extends the life of the cultures. Companies who freeze dry their probiotics (which if I’m not mistaken, each of these companies do), but having them shipped in very high temperatures can and does kill probiotic microorganisms so it’s definitely a concern. Ideally, it’s better to stock up during the winter so that you don’t have your product stuck in the back of a hot truck before it gets to you.
Eating foods rich in good bacteria and using probiotic supplements may help provide protection from inflammatory bowel diseases, including ulcerative colitis and Crohn’s disease. The evidence is stronger, however, for an improvement in ulcerative colitis, while Crohn’s disease may not benefit as greatly. In addition, there is ongoing research studying the role of probiotics in gluten issues, including celiac disease.

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.
However, it’s not just digestive woes that probiotics can help address. A clinical case series followed 300 patients who took a probiotic mixture of L. acidophilus and L. bulgaricus. They documented that 80% of acne patients had some degree of clinical improvement, particularly effective in inflammatory acne. Later, an Italian study involving 40 patients found L. acidophilus and B. bifidum supplementation produced better clinical outcomes in acne as well as better tolerance and compliance with antibiotics [2].
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.
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