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.”


Disclaimer: While we work to ensure that product information is correct, on occasion manufacturers may alter their ingredient lists. Actual product packaging and materials may contain more and/or different information than that shown on our Web site. We recommend that you do not solely rely on the information presented and that you always read labels, warnings, and directions before using or consuming a product. For additional information about a product, please contact the manufacturer. Content on this site is for reference purposes and is not intended to substitute for advice given by a physician, pharmacist, or other licensed health-care professional. You should not use this information as self-diagnosis or for treating a health problem or disease. Contact your health-care provider immediately if you suspect that you have a medical problem. Information and statements regarding dietary supplements have not been evaluated by the Food and Drug Administration and are not intended to diagnose, treat, cure, or prevent any disease or health condition. Amazon.com assumes no liability for inaccuracies or misstatements about products.


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.
As the best-selling author of Happy Gut and a medical doctor who specializes in gut health and once suffered from IBS (irritable bowel syndrome), I have experienced for myself, as well as see on a daily basis, how a disrupted gut flora opens the door for unfriendly microbes to step in and take over, creating all sorts of pandemonium that causes patients to gain weight, feel sick and tired, and become more disease-prone.

The Number of CFUs The quality of a probiotic supplement has more to do with strains and how many CFUs it provides. (CFU stands for colony forming units, and it refers to the amount of live microorganisms in your supplement.) Although recommendations may vary, Gans says to look for probiotics with at least 1 billion CFUs: “Doses will typically range from 1 billion to 10 billion CFUs for adults; although doses for children are often under 1 billion.”


Better Health Review named Dr. Ohhira’s Probiotics 12 Plus on its list of the top probiotic supplements on the market. It contains less than a billion active probiotic cells per dosage, but it adds vitamins, minerals and other micronutrients for optimal health. It claims to be 100 percent vegetarian. Better Health Review gives Dr. Ohhira’s Probiotics 12 Plus a rating of 3.5 on a scale of 5.
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.

Overall, Enzymatic Therapy Acidophilus Pearls are a great daily probiotic supplement. They give you a ton of flexibility and is convenient since it doesn’t need to be refrigerated and can be taken with or without food! This probiotic makes on-the-go belly support a breeze. All in all, Enzymatic Therapy Acidophilus Pearls finally make it easy to travel with probiotics, are simple to take, and can give you the piece of mind that the money you’re spending on probiotics isn’t being wasted at the first sign of stomach acid.  Read the full review here… or click here to go buy it now!


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.

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.”
Although people often think of bacteria and other microorganisms as harmful “germs,” many microorganisms help our bodies function properly. For example, bacteria that are normally present in our intestines help digest food, destroy disease-causing microorganisms, and produce vitamins. Large numbers of microorganisms live on and in our bodies. Many of the microorganisms in probiotic products are the same as or similar to microorganisms that naturally live in our bodies.

If you've tried a probiotic after following these steps and it doesn't seem to be working for you (or you just want some extra guidance in choosing one), head to your doctor (or a dietitian) to get a recommendation. "Have a thorough discussion with your doctor to make sure you are taking the appropriate bacterial strain for the appropriate reason," advises Dr. Ivanina. "Then, follow up after taking the probiotic to make sure it is having the intended effect."


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.

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.


Yes, they may help. Lebwohl says there are reputable studies that show a link between the use of probiotics and the reduction in IBS symptoms, citing this meta-analysis. It's estimated that 11 percent of the world population complains of symptoms like abdominal cramps, diarrhea, constipation, excessive gas and/or mucus in their stools. While for some the condition can be attributed to certain dietary triggers, others appear to be stress-related, which brings us to the heart of where many claims about the effectiveness of probiotics lie—in the gut-brain axis.
About 60 to 80 percent of our immune system lives in our gut. Imbalances in the gut’s microbiome (which is primarily made up of bacteria) lead to digestive issues, while many many other potential effects can be felt throughout the body—from feelings of fatigue to depression, thyroid dysfunction, autoimmunity, and a host of skin issues. Conditions like rosacea, psoriasis, eczema, and acne are really inflammatory conditions, and often a manifestation of something that is happening deeper within the body. When you fix the gut (which, depending on your health, might include getting rid of an infection like Candida, eating a clean diet, and taking a probiotic), skin issues often resolve as well.
You may have heard some questions over whether SBOs are safe: The NIH has a presumed case report, which hasn’t been 100 percent verified, of someone with Lymphoma getting septicemia from taking a SBO (the organism B. subtilis). Some say that if you have leaky gut, you should heal it before supplementing with SBOs. If you are immunocompromised or have cancer, you can consult with a physician first to be safe.
Many avenues of research have examined probiotics benefits for skin, especially in children. Meta-analyses have found that probiotic supplements are effective in the prevention of pediatric atopic dermatitis and infant eczema. The integrity of gut bacteria is also connected to the development of acne, although the way this happens is still unclear.
If you are seeking non-dairy yogurt options, there are several that contain live probiotic cultures. Yogurts made from rice, soy and coconut milk are available on the market and also contain added probiotics that can provide the same benefits. Other alternative sources of probiotics include eating fermented foods like Brewer’s yeast, miso, sauerkraut, or micro algae. Whatever the source, always look for “live and active cultures” on the label.

Food allergies and sensitivities both involve the immune system, albeit in different ways. Many types of probiotics can benefit and help modulate the immune system, and they can calm these conditions, not only via immune regulation, but also through prevention of intestinal permeability, improved intestinal motility, and communication with your genes.


After further analyzing the data, the researchers found that they could predict whether the probiotics would take hold in people's guts by examining their microbiome and gene expression in the gut taken at the start of the study. However, this prediction method needs to be confirmed in future studies. The researchers called for further research to better understand why some people resist colonization by probiotics, as that future research may enable researchers to counteract the resistance.
Others scientists are more hopeful. Finding out how exactly probiotics work in regards to allergies is an important step in that process. Some studies show that some strains of bacteria can affect how our T cells (an immune cell responsible for the big immune responses) function. Others suggest that they may reduce the production of a part of the immune system called immunoglobulin E, which is produced in excess during an allergic reaction.
Overall, Align Probiotic is one of the better “daily” probiotics out there.  It’s easy to take, comes in convenient packaging and doesn’t require refrigeration.  And it has some research showing it helps with gas, bloating and constipation, especially in women with IBS.  Lots of things to like about this probiotic!  Read the full review here… or click here to go buy it now!
A large analysis reviewed available research and determined that probiotics help lower blood pressure by improving lipid profiles, reducing insulin resistance, regulating renin levels (a protein and enzyme secreted by the kidneys to lower blood pressure) and activating antioxidants. Researchers consider them valuable prospects in the treatment of high blood pressure because their side effects are generally minimal or nonexistent. (82, 83)
 Do you ever feel like your thinking is clouded, where it is hard to think, hard to focus, and hard to recall events that happened recently? You may have a case of brain fog. Brain fog is a group of neurocognitive symptoms that make a person feel groggy and not quite “with it.” There are many causes, such as lack of sleep, a hangover, fever and illness, neurotoxins such as MSG, chronic inflammation, infections, autoimmune disease, heavy metals toxicity, consumption of reactive foods, vitamin deficiencies, blood sugar fluctuations, hormonal fluctuations, and bacterial by-products. The end result is neuroinflammation, which causes the clouded thinking.
Step No. 1 is consume more sour foods — it’s the top way probiotics benefits can be accessed. Embrace what I call “the power of sour” with sour foods like apple cider vinegar and fermented vegetables. They contain some probiotics, but also they contain certain types of acids like gluconic acid and acetic acid, healthy acids that support the function of probiotics (even functioning like prebiotics in some cases).

Although these capsules are more expensive than other options on the market, if you suffer from ulcerative colitis, irritable bowel syndrome, or pouchitis, this probiotic will help manage your symptoms. VSL contains eight different probiotic strains (and more good bacteria than other brands) to alleviate symptoms such as bloating, cramping, and diarrhea. There are 60 capsules per bottle.
​​​​​​AZO Complete Feminine BalanceTM is a daily probiotic supplement designed for the unique needs of women. Researchers that formulated the blend started by selecting species that are dominant in the healthy vaginal microbiota. Then they further refined the formula by selecting strains of probiotics that flourish in the vagina. The blend is clinically proven to help protect vaginal/feminine health.*
"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."

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 factor strain-specific benefits into our efficacy score, we referenced the information in these guides. Products were rewarded for containing strains on these lists. Additionally, measured levels of each strain were compared to what is thought to be effective based on these guides, and scores were scaled accordingly. In cases where products did not list strain-specific amounts, or their listed strains were not included in these guides, total measured CFUs were compared to a general effectiveness threshold of 1 billion CFUs cited by research published in the American Journal of Clinical Nutrition11.

Because poor gut health is related to autoimmune responses like those found in rheumatoid arthritis (RA), probiotics have been a proposed treatment option for the condition. Only a few studies have been conducted in humans, and only one testing L. casei 01, a particular probiotic strain, was able to find a decrease in RA inflammation and progression of the disease.
"Probiotics are live microorganisms which when administered in adequate amounts, confer a health benefit." 1 In general, probiotics are similar to the beneficial bacteria that live naturally in your digestive tract. When taken daily, probiotics can help support digestive and immune health. You may think of bacteria as something harmful to your body. But it's important to have a balance of good bacteria in your digestive tract, which can be negatively impacted from factors such as diet and travel. Probiotics are beneficial bacteria your body may need to support good digestive health.∗

The best case for probiotic therapy has been in the treatment of diarrhea. Controlled trials have shown that Lactobacillus GG can shorten the course of infectious diarrhea in infants and children (but not adults). Although studies are limited and data are inconsistent, two large reviews, taken together, suggest that probiotics reduce antibiotic-associated diarrhea by 60%, when compared with a placebo.

"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 said in a statement. "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." Segal added, "This opens the door to diagnostics that would take us from an empiric universal consumption of probiotics, which appears useless in many cases, to one that is tailored to the individual and can be prescribed to different individuals based on their baseline features."

Disclaimer: While we work to ensure that product information is correct, on occasion manufacturers may alter their ingredient lists. Actual product packaging and materials may contain more and/or different information than that shown on our Web site. We recommend that you do not solely rely on the information presented and that you always read labels, warnings, and directions before using or consuming a product. For additional information about a product, please contact the manufacturer. Content on this site is for reference purposes and is not intended to substitute for advice given by a physician, pharmacist, or other licensed health-care professional. You should not use this information as self-diagnosis or for treating a health problem or disease. Contact your health-care provider immediately if you suspect that you have a medical problem. Information and statements regarding dietary supplements have not been evaluated by the Food and Drug Administration and are not intended to diagnose, treat, cure, or prevent any disease or health condition. Amazon.com assumes no liability for inaccuracies or misstatements about products.
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.
With Prebiotin, you can easily add prebiotic fiber to your diet without worrying about eating huge amounts of troublesome foods or hunting down hard-to-find ingredients. You also won’t have to worry about loading up on high-calorie foods that can negatively affect any effort to lose weight. Combining Prebiotin prebiotic fiber with a diet enriched with probiotic foods can only help your effort to positively influence the bacterial balance in your lower gut.
Coming in at a close second, our runner-up as the best probiotic for women is the Culturelle Women’s Healthy Balance Probiotic. As the #1 recommended brand by pharmacists, it is easy to see why so many women are turning to Culturelle for their digestive health. Featuring the LGG culture and a laundry list of other healthy bacteria, this probiotic offers a wonderful balance between digestive and feminine health. The Culturelle Women’s Healthy Balance Probiotic is also taken in an easy, chewable tablet and can even be taken during pregnancy, making it one of the most versatile formulas we reviewed!
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