Caution needs to be taken by everyone who chooses to take these supplements, but this is especially true for children, pregnant women, elderly people, and people with compromised immune systems. For people with compromised immune systems due to disease or treatment for a disease (such as cancer chemotherapy), taking probiotics may actually increase one's chances of getting sick. It has been shown that the use of various probiotics for immunocompromised patients or patients with a leaky gut has resulted in infections and sepsis (infection of the bloodstream). One case of bacteremia (bacteria in the bloodstream) was recently found when someone with active severe inflammatory bowel diseases with mucosal disruption was given Lactobacillus GG. Always speak with a doctor before taking any supplement under these circumstances.

Bacillus is an interesting genus because these microbes have the ability to form endospores, tough outer coatings, when conditions are not suitable for them to flourish. There are five species of probiotic Bacillus: clausii, coagulans, indicus, licheniformis, and subtilis. Not every species of Bacillus is probiotic. Some Bacillus species are usually pathogens. Bacillus may normally be found in the GI tract, but they generally do not take up residence for long and will pass through and be eliminated if not replenished. Bacillus are common food spoilage organisms and are also found in probiotic supplements and in soil, air, and water.
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.

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.”


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.
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.
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.

Best Probiotic says that Suprema Dophilus, manufactured and distributed by Vitabase, enjoys the highest customer rating in the market. Specially coated to help the bacteria spread through your entire digestive tract, its website claims over four billion viable cells per capsule, including five lactobacillus strains and three bifidobacteria cultures. Best Probiotic says that Suprema Dophilus also contains fructo-oligosaccarides to increase the life span of the bacteria.
Although many manufacturers will make claims regarding the benefit of probiotics for all sorts of disorders, there is not always research to back up those claims. It can be difficult to conduct quality research on probiotics due to the wide variety of strains available. And many studies show mixed results. However, given that, there is some research support for the use of probiotics for the following health conditions:
Next time you pack your travel beauty bag, slip a shelf-stable probiotic in there to preempt bathroom emergencies, Fasig says. Look for one that contains Lactobacillus acidophilus, Lactobacillus sporogenes, Bifidophilus bifidum, and Sacchromyces boulardii strains ($20, amazon.com), which Fasig says can improve your intestinal health to fix issues with constipation or diarrhea.
Popular probiotic foods include yogurt, kimchi, sauerkraut, and kombucha. While delicious, these foods don’t claim specific amounts of whatever microorganisms they may contain. By contrast, Probiotic All-Flora is optimally formulated with the right amounts of the right strains to deliver researched benefits. The label lists out the DNA-tested flora that make up that ideal 10 billion CFU in just one capsule daily. So probiotic supplements actually have more reliable strain benefits than probiotic foods.

While more research is necessary to truly understand the widespread benefits of different probiotic strains, we do know that not all probiotics are created equal. The Lactobacilli, for instance, live in our digestive, urinary and genital systems and can be found in some fermented foods like yogurt. Bifidobacteria normally live in the intestines as lactic acid bacteria, and are also found in fermented foods. According to nutrition expert Alex Caspero, RD, “For certain conditions, you want to ensure you are taking the strand that is most likely to benefit you.” Here is a simple breakdown to help you determine the best probiotic for you.
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.
To boost the immune system, B. Lactis is a promising choice. One study had participants taking either a probiotic or a placebo for 6 weeks. At the end of the period, researchers measured antibody levels and found greater increases in antibodies of the B. Lactis group than in placebo participants, concluding that this probiotic may help improve immune function [1]. In addition, a 2009 study found that supplementation of the strain B. Lactis DN-173 led to self-reported improvements in digestive comfort [2].
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.
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.
Garden of Life RAW Probiotics are some of the most popular out there – and for good reason. Let’s start with the basics: You’ll get 85 billion CFUs and 31 to 33 probiotic strains out of your daily, whole-food, gluten-free, soy-free probiotic, which helps support the immune system, a healthy thyroid, nutrient absorption, digestive function, and a healthy microbial balance. 

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.
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Probiotics' side effects, if they occur, tend to be mild and digestive (such as gas or bloating). More serious effects have been seen in some people. Probiotics might theoretically cause infections that need to be treated with antibiotics, especially in people with underlying health conditions. They could also cause unhealthy metabolic activities, too much stimulation of the immune system, or gene transfer (insertion of genetic material into a cell).
DNA Shift is a once-daily, powerful probiotic delivering 50 billion CFUs and 11 probiotic strains. It’s perfect for both men and women who want to improve their gut and brain health. With long-term use, you may even see improved mood and energy levels. This probiotic can help relieve the following: symptoms of gas and bloating, constipation indigestion, irregularity, leaky gut, and diarrhea induced by antibiotics.
I didn’t know there was much of a difference between probiotics until I did some research. After realizing the ones I had been getting were probably not doing anything for me, I wanted to invest in a better option. This brand checked all the boxes and was still really affordable! I’ve been taking them for about a week now and I can tell a difference! The first few days I didn’t feel too great but realized it was because this probiotic was actually doing something for me and rebalancing my gut. Now I feel less bloated and all around healthier. I will definitely be getting more!

While taking a daily probiotic supplement may seem like an easy answer to cure common gut ailments, it’s always best to try for a food first approach, since you can get probiotics from the foods you eat. Probiotics can be found in foods such as yogurt, cheese, miso, sauerkraut, and kimchi. But, adding a supplement into the mix if you haven’t achieved the desired effect through diet alone can be effective.


The recent buzz has helped bring probiotics into the main stream.  Due to being covered on major news sites and television personalities, probiotic supplements are now more accessible than ever.  The main benefits of probiotics begin within the gut and digestive system.  The gut plays such an important role, that the level of healthy bacteria in our bodies can actually alter our mood.  It’s true!  What we eat actually affects how we feel.  This is why the gut has been called our “second brain”.
"Although all of our probiotic-consuming volunteers showed probiotics in their stool, only some of them showed them in their gut, which is where they need to be," co-senior author Eran Segal, a computational biologist at the Weizmann Institute, said in the statement. "If some people resist and only some people permit them, the benefits of the standard probiotics we all take can't be as universal as we once thought." 

That doesn't mean that all probiotics, or probiotic-containing foods are created equal. So what should you look for? "There is a lot of 'noise' in this space as more and more 'food products' are coming out with Probiotics," Dr. Shekhar K. Challa, a gastroenterologist and the author of Probiotics For Dummies tells The Huffington Post. "Unfortunately it is impossible to quantitate the CFU's of probiotics in most food products."
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.”
The concept of probiotics is credited to Élie Metchnikoff, a Russian scientist born in the mid-1800s, whose work provided profound insights into immunology and microbes. He developed a theory about aging that over the years had been forgotten in mainstream medicine but is now embraced by many scientists: namely, that health is influenced by toxic bacteria in the gastrointestinal (GI) tract. He is said to have noticed that people who lived to be over 100 years old in the Balkan States and Russia drank sour milk, which we now call yogurt or kefir, every day. In fact, Bulgarian yogurt cultures even today are regarded as highly therapeutic.
If you have a tendency to forget to take your probiotics (which, let’s be honest, we all have), try storing them in a place that you look at directly each and every day. We recommend somewhere like your bathroom sink near your toothbrush or even on your kitchen counter, so you never miss a dosage! This one can be taken with or without food, and it doesn’t have to be stored in the fridge – perfect!
The authors discuss the need for “pscyhobiotics” (probiotics that impact brain function) in handling the development of these conditions. This anti-inflammatory quality is what seems to interest researchers most. While no studies have been conducted in humans, early research suggests that, in animals, probiotic supplements may help alleviate symptoms of anxiety by reducing inflammation along this gut-brain connection.
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.
Known as the most clinically proven effective probiotic strain, Lactobacillus rhamnosus GG (otherwise known as “LGG”) has been clinically proven to maintain healthy numbers of bacteria and yeast for optimal digestive health. This powerful probiotic is also paired with some of the best probiotic strains for feminine health, making it an ideal choice for any woman that is looking for complete care from her probiotic.
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.
Renew Life Ultimate Flora offers 30 billion CFUs with 10 scientifically studied strains of Bifidobacterium and Lactobacillus, which according to current scientific research, are the two most prevalent good bacteria found in a healthy gut. In other words, you might choose these if you’re seeking a careful balance designed to re-establish proper immune health and digestive equilibrium.
What’s more, your bacterial makeup does more than just boost or bully your immune system; the existence of good and bad bacteria affect your mood and energy levels, relieve (or contribute to) a sensitive stomach (including lactose intolerance and irritable bowel syndrome/IBS), affect your mood, and even support (or hinder) a healthy body weight. (Fascinating fact: Scientists can predict weight with 90% accuracy based on your gut’s bacterial makeup, but only with 58% accuracy based on your genes. Bacteria counts!)
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.

Women’s health expert Dr. Amy Myers is a goop-trusted authority on subjects from autoimmunity and Candida to thyroid dysfunction; and she’ll be speaking IRL at our first wellness summit on June 10. Here, Myers helps us evaluate the increasing buzz around probiotics, and outlines the ins and outs of selecting a particular supplement (whether hers or other brands). Plus, we’ve rounded up our probiotic essentials, from inner beauty powders to favorite fermentation recipes, in one guide:
Two dangerous diseases in newborns, necrotizing enterocolitis (NEC) and neonatal sepsis, may meet their match with well-designed probiotic supplements. Both of these conditions are common in premature babies and are most dangerous in low birth weight and very low birth weight infants. Research has confirmed that when a pregnant mother takes high-quality probiotics during pregnancy, her baby is significantly less likely to develop either NEC or sepsis, particularly when the baby is breastfed after birth (and mom is still taking the supplements) and/or when probiotics are added to formula. A probiotic supplement with multiple strains seems to be the most effective in these cases.
"In fact," she continues, "80% of immune system cells are found in the gut. In addition to the well-known GI benefits of minimizing bloat, gas, constipation, and diarrhea, probiotics aid in digestion by extracting nutrients, helping your body absorb minerals, produce vitamins, and make brain chemicals, including over 30 neurotransmitters along with mood-enhancing serotonin. A healthy person has over 100 trillion microbes, generally a five to one ratio of helpful to harmful."
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.
"There is an increasing interest in probiotic interventions," wrote the authors of one of the most recent studies, a meta-analysis of previous research in a recent issue of the Journal of the American Medical Association. Those researchers found that probiotics were particularly useful against a common gastrointestinal problem: antibiotic-associated diarrhea (AAD).
"People have thrown a lot of support to probiotics, even though the literature underlying our understanding of them is very controversial; we wanted to determine whether probiotics such as the ones you buy in the supermarket do colonize the gastrointestinal tract like they're supposed to, and then whether these probiotics are having any impact on the human host," says senior author Eran Elinav, an immunologist at the Weizmann Institute of Science in Israel. "Surprisingly, we saw that many healthy volunteers were actually resistant in that the probiotics couldn't colonize their GI tracts. This suggests that probiotics should not be universally given as a 'one-size-fits-all' supplement. Instead, they could be tailored to the needs of each individual."
Most of the high-quality probiotics that are available on the market today share the same annoying pitfall: they need to be refrigerated. If losing your supplements in the abyss of your fridge isn’t exactly your idea of a good time, the Garden of Life Dr. Formulated Once Daily Women’s Probiotic is just for you! This probiotic comes with a Shelf Stable Potency Promise, meaning there is no need for refrigeration.
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.
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.
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.") 
Renew Life Ultimate Flora offers 30 billion CFUs with 10 scientifically studied strains of Bifidobacterium and Lactobacillus, which according to current scientific research, are the two most prevalent good bacteria found in a healthy gut. In other words, you might choose these if you’re seeking a careful balance designed to re-establish proper immune health and digestive equilibrium.
Pure Therapeutics Power Probiotic 100B offers 100 billion CFUs of 4 powerful probiotic strains, including science darling, the HN019 strain of Bifidobacterium lactis. Since environmental factors, including moisture, oxygen and heat, can degrade the stability of your probiotics, Pure Therapeutics 100B is delivered in nitrogen-purged aluminum blister pacts, which ensure viability until the probiotic hits your system. No refrigeration is required. 
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