What are the benefits of probiotics? They’ve certainly come a long way since I first began writing about them some 30 years ago. Back then, other than a few diehard fermented food proponents, there were just a handful of us in the alternative health community promoting the idea of probiotic supplements beyond eating yogurt, drinking kefir, and trying to figure out what to do with sauerkraut. Now, it’s a different story. Everybody’s talking about the benefits of probiotics. Probiotics are the “it” girl of the day. And like that supermodel who can be found on every magazine cover in the world–until she’s replaced by the next “it” girl–it’s hard to find any product that doesn’t now have a probiotic enhanced version. There are probiotic:

• Toothpastes¹ http://www.prweb.com/releases/2010/04/prweb3880894.htm
• Gum² http://www.jarrow.com/product/571/Jarro-Dophilus_Oral_Probiotic_Gum_+_Vitamin_C
• Flavored waters³ http://www.goliveprobiotics.com/
• Milk⁴ http://dairybalancemilk.com/
• Cookies, candies, and ice creams⁵ http://www.activedlites.com/
• Soap⁶ http://drohhiraprobiotics.com/dr_ohirra_probiotic_kampuku_soap.php
• Shampoo⁷ http://tricoligo.com/index.php?option=com_content&view=article&id=63&Itemid=114

You name it and companies are now “probiotisizing” it. How useful any of these products are is open to question; and the FDA, of course, has not approved probiotics for the treatment of any disease or condition. So in fact, most claims for the benefits of “probiotisized” products fall outside the law.⁸ “Dannon Agrees to Drop Exaggerated Health Claims for Activia Yogurt and DanActive Dairy Drink.” Federal Trade Commission. For Release: 12/15/2010. (Accessed 27 July 2013.) http://www.ftc.gov/opa/2010/12/dannon.shtm Then again, just because some claims fall outside the law, doesn’t mean they’re necessarily untrue. But really, for the most part, isn’t that the entire basis of alternative health: factual claims that are ahead of the law? So, despite the lack of support from the FDA and the FTC, it is pretty much known that probiotics offer a number of demonstrable benefits. For example:

Probiotics promote a healthy immune system and decrease the incidence of colds, allergies, and even eczema by boosting your immune system. For years I’ve been saying that beneficial bacteria in your intestinal tract are responsible for as much as 60-70% of your immune system function. Surprise! According to the latest estimates, I may have been understating the case. Some experts now claim that your beneficial bacteria may account for as much as 80-90% of your immune function. How is this possible? As it turns out, probiotics are multifaceted when it comes to your immune system. By lining every square inch of your intestinal tract, they not only provide a barrier to entry for many microorganisms that arrive with your food,⁹ Erika Isolauri, Yelda Sütas, Pasi Kankaanpää, Heikki Arvilommi, and Seppo Salminen. “Probiotics: effects on immunity1,2,3.” AJCN.Am J Clin Nutr February 2001   vol. 73  no. 2  444s-450s. http://ajcn.nutrition.org/content/73/2/444s.full.pdf+html they also directly kill many pathogens such as bad bacteria, viruses, fungi, parasites, and yeast. They also function as immunomodulators and produce a number of immune factors such as lactoferrin that directly boost your immune function as well as a number of B vitamins that offer nutritional support for your immune system. And finally, it is estimated that some 70% of your immune system cells reside within your colon in a layer of lymphoid tissue just below the surface epithelial cells. The net result is that studies have shown, for example, that probiotic supplements can significantly prevent recurrent streptococcal pharyngitis and/or tonsillitis in adults.¹⁰ Francesco Di Pierro, Teresa Adam, Giuliana Rapacioli, Nadia Giardini, Christian Streitberger. “Clinical evaluation of the oral probiotic Streptococcus salivarius K12 in the prevention of recurrent pharyngitis and/or tonsillitis caused by Streptococcus pyogenes in adults.” Expert Opinion on Biological Therapy. March 2013, Vol. 13, No. 3 , Pages 339-343. http://informahealthcare.com/doi/abs/10.1517/14712598.2013.758711 Other studies, conducted in China, found that children aged 3 to 5 who were treated with two kinds of probiotics had a 53 percent lower rate of fevers, a 41 percent decrease in coughs, and a 28 percent decrease in runny noses. And antibiotic use was lowered by 84 percent in the children who were on the probiotics.¹¹ Gregory J. Leyer,  Shuguang Li, Mohamed E. Mubasher, Cheryl Reifer, Arthur C. Ouwehand, “Probiotic Effects on Cold and Influenza-Like Symptom Incidence and Duration in Children.” Pediatrics  Vol. 124  No. 2  August 1, 2009 pp. e172 -e179. http://pediatrics.aappublications.org/content/124/2/e172.full.pdf+html

For related reasons, optimizing your intestinal flora is one of the most effective natural allergy remedies as it can make a major difference in treating a whole range of allergic and autoimmune conditions such as Crohn’s disease,¹² Elizabeth C. Verna, Susan Lucak. “Use of probiotics in gastrointestinal disorders: what to recommend?” Therap Adv Gastroenterol. 2010 September; 3(5): 307–319.  http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3002586/ but not necessarily—as we shall see—Irritable Bowel Disease. That said, optimizing gut flora with probiotics can help with a whole range of intestinal problems ranging from diarrhea to constipation (two sides of the same coin) and from bloating to flatulence (also two sides of the same coin).

The Benefits of Probiotics according to the Medical Studies

Needless to say, when something becomes this popular, researchers start to appear to grab their share of funding. Unfortunately, until a drug company sees a way to turn a patented profit on probiotics, you’re unlikely to see the large scale double blind studies everyone, including the FDA, is so enamored of. Nevertheless, these initial studies, although hardly definitive, are indeed indicative and therefore worth looking at.

Probiotics for Diarrhea in Irritable Bowel Syndrome

As we mentioned earlier, probiotics have been used to treat diarrhea caused by IBD and IBS, apparently with some anecdotal success. However, a recent study of probiotics to treat diarrhea associated with IBS found similar improvements among those who consumed probiotics compared with those who did not.¹³ Lesley M Roberts, Deborah McCahon, Roger Holder, Sue Wilson, and FD Richard Hobbs. “A randomised controlled trial of a probiotic ‘functional food’ in the management of irritable bowel syndrome.” BMC While previous small studies have suggested some probiotic efficacy, the authors concluded that “This trial does not provide evidence for effectiveness of a probiotic in IBS.” The study included more patients (179) and a longer study period (12 weeks) than did previous research.  But before you get too upset by the results of this recent study, it’s worth noting that there are some holes in it. First of all, the test product used in the study was a Danone yogurt that contained 10.25 billion colony forming units of Bifidobacterium lactis per cup and 1.2 billion of S. thermophilus and L. bulgaricus, consumed twice a day. Unfortunately, this didn’t match the formulas that produced successful results in the previous studies of patients with IBS. Those formulas contained Bifidobacterium lactis, L. bulgaricus, and Streptococcus thermophilus. Not even in the scientific world does matching just one out three strains negate earlier studies; it merely means that the mix you used doesn’t work. It also has no bearing on the results achieved by people using dedicated probiotics supplements that contained other powerful strains (such as Salivarius, Acidophilus, Plantarum, and Rhamnosus). It also should be noted that probiotics in the form of dietary supplements usually contain no dairy, which in itself can cause diarrhea not only in IBS patients, but in many healthy patients.

Probiotics May Help Prevent Antibiotic-Related Diarrhea

A review published May 31, 2013, in the Cochrane Database of Systematic Reviews found that probiotics are safe and effective when it comes to preventing Clostridium difficile associated diarrhea in children and adults taking antibiotics.¹⁴ oldenberg JZ, Ma SS, Saxton JD, Martzen MR, et al. “Probiotics for the prevention of Clostridium difficile-associated diarrhea in adults and children.” Cochrane Database Syst Rev. 2013 May 31;5:CD006095. http://www.ncbi.nlm.nih.gov/pubmed/23728658 An examination of 23 trials that enrolled a total of 4213 participants, probiotic use was associated with a significant 64% reduction in risk. The use of probiotics also helped relieve symptoms of abdominal cramping, nausea, fever, soft stools, flatulence, and taste disturbance. The interesting thing about this “examination” study is that it was a meta study; in other words, it merely reviewed the data from previous studies and had no control over the strains of probiotics used, nor their amounts. Nevertheless, as the study noted, “These results…were similar whether considering trials in adults versus children, lower versus higher doses, different probiotic species, or higher versus lower risk of bias.”

Incidentally, medical researchers have found an even quicker way than supplementation to rebalance intestinal bacteria. It’s called a fecal transplant. Once the feces from a healthy person is diluted with a liquid, like salt water, it is pumped into the intestinal tract of the suffering patient via a colonoscope, a tube run through the nose into the stomach or small intestine, or an enema. In cases of patients infected with C. diff, despite the “ick” factor, this can produce a very rapid improvement in symptoms.

Probiotics During Pregnancy May Ward Off Eczema, Food Allergy

In research reported in the December 2012, issue of the Journal of Allergy and Clinical Immunology, infants whose mothers took probiotics during pregnancy and while breast-feeding were less likely to develop eczema.¹⁵ Samuli Rautava, Essi Kainonen, Seppo Salminen, Erika Isolauri. “Maternal probiotic supplementation during pregnancy and breast-feeding reduces the risk of eczema in the infant.” The Journal of Allergy and Clinical Immunology. Volume 130, Issue 6 , Pages 1355-1360, December 2012. http://www.jacionline.org/article/S0091-6749(12)01464-9/abstract The mothers all had a history of allergy, so their children were at high risk. About 30% of infants whose mothers took probiotics developed eczema compared with 79% of infants whose mothers did not. However, the study found no difference in the incidence of other allergies at age 2 years, including milk, wheat, soy, and dog and cat dander. (These results, of course, could be strain dependent. Different strains could produce different results.) And in a separate review published online April 17, 2013, the authors write, “Twenty-three randomized, placebo-controlled intervention studies regarding the clinical effect of probiotic supplementation on development of [food] allergy and eczema in particular have been published. Around 60% of the studies show a favorable effect decreasing the risk of eczema during the first years of life.” These results are especially interesting in that they show the ability of mothers to pass on the benefits of probiotics to their infants.

Allergic Rhinitis Eased by Antihistamine and Probiotics

According to a study published in the July 2012 issue of the International Journal of Pediatric Otorhinolaryngology, supplementing the antihistamine levocetirizine with the probiotic Lactobacillus johnsonii EM1 effectively alleviated the symptoms of perennial allergic rhinitis in a group of Taiwanese children.¹⁶ Ko-Haung Lue, Hai-Lun Sun, Ko-Hsiu Lu, et al. “A trial of adding Lactobacillus johnsonii EM1 to levocetirizine for treatment of perennial allergic rhinitis in children aged 7-12 years.” International Journal of Pediatric Otorhinolaryngology. Volume 76, Issue 7, July 2012, Pages 994-1001. http://www.sciencedirect.com/science/article/pii/S0165587612001978 The study was somewhat small, with just 62 children. In addition, as the researchers reported, the “open-label design makes it difficult to compare the clinical response between the 2 treatment groups, but any bias may have been decreased by using the crossover method.” Another issue to be resolved is whether the benefit will extend beyond 12 weeks—and what other strains produce a similar result.

Probiotics Cut Risk for Hepatic Encephalopathy in Half

According to a study published in the Journal of Gastroenterology and Hepatology, probiotics were effective in helping to prevent a first episode of overt hepatic encephalopathy (confusion and possible coma as the result of liver failure) in patients with cirrhosis compared with patients not receiving probiotics.¹⁷ P. Sharma, BC Sharma, A. Agrawal, SK Sarin. “Primary prophylaxis of overt hepatic encephalopathy in patients with cirrhosis: An open labeled randomized controlled trial of lactulose versus no lactulose.” Journal of Gastroenterology and Hepatology. Volume 27, Issue 8, 1329–1335, August 2012. http://onlinelibrary.wiley.com/doi/10.1111/j.1440-1746.2012.07186.x/abstract This study involved patients with no more than a low level of hepatic encephalopathy at the outset of the study and was therefore for prevention, not treatment. Although the use of probiotics is not standard for such patients, previous research has also shown their benefit under these circumstances. In fact, that earlier research found that prebiotics were even more beneficial than probiotics—but then again, probiotics such as FOS merely optimize the environment for the growth of probiotics.¹⁸ S. Shukla1, A. Shukla1, S. Mehboob1, S. Guha. “Meta-analysis: the effects of gut flora modulation using prebiotics, probiotics and synbiotics on minimal hepatic encephalopathy.” Alimentary Pharmacology & Therapeutics. Volume 33, Issue 6,  pages 662-671, March 2011. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2036.2010.04574.x/abstract

Possible Cholesterol-Lowering Effects

A review of the research on the cholesterol-lowering benefits of probiotics, published in Clinical Lipidology, showed conflicting results, with probiotics resulting in improved lipid profiles in some studies but not others.¹⁹ Guo Zhuang, Xiao-Ming Liu, Qiu-Xiang Zhang, Feng-Wei Tian, et al. “Research Advances With Regards to ClinicalOutcome and Potential Mechanisms of the Cholesterol-Lowering Effects of Probiotics.” Clin Lipidology. 2012;7(5):501-507. http://www.scribd.com/doc/145033978/Pro-Biotics The authors suspect that the differences may be a result of different mechanisms of action, but they felt more research needs to be done. In fact, the differences may be explained a lot more simply: the different studies they reviewed were all over the map in terms of both the strains of probiotics used and the amounts consumed by each subject. Sometimes, very bright researchers get so lost in details that they can’t see what’s right in front of their eyes. Or perhaps it’s as simple as more research means more grant money.

But the even bigger question is: why is it that researchers do not afford natural treatments the same respect they grant pharmaceutical drugs? Would any research that lumped all antibiotics together in a study of the effectiveness of antibiotics in treating MRSA get published in a peer reviewed journal? Obviously, never! Different antibiotics differ in their effectiveness from illness to illness. How can you, then, lump all strains of probiotics together in a meta analysis and arrive at a blanket statement concerning their effectiveness in terms of anything? You can’t. Different strains of probiotics are as different as different strains of antibiotics–far more different–and far more complex–in fact.

Probiotics and Infection Risk After Colorectal Cancer Surgery

Chinese patients who received probiotics both before and after colorectal cancer surgery experienced fewer infections after the operation, according to results of a study published online in December of 2012, in the American Journal of Clinical Nutrition.²⁰ Zhi-Hua Liu, Mei-Jin Huang,  Xing-Wei Zhang, et al. “The effects of perioperative probiotic treatment on serum zonulin concentration and subsequent postoperative infectious complications after colorectal cancer surgery: a double-center and double-blind randomized clinical trial.” Am J Clin Nutr December 2012   ajcn.112.040949. http://ajcn.nutrition.org/content/early/2012/12/10/ajcn.112.040949 Patients receiving probiotics also experienced significant decreases in bacterial translocation and intestinal wall permeability.

Probiotics Affect Brain Activity

Perhaps the most interesting study, however, was just published in the June issue of Gastroenterology. It provides the first evidence in humans that probiotics in the diet can modulate brain activity.²¹ sten Tillisch, Jennifer Labus, , Lisa Kilpatrick, et al. “Consumption of Fermented Milk Product With Probiotic Modulates Brain Activity.” Gastroenterology Volume 144, Issue 7 , Pages 1394-1401.e4, June 2013.  http://www.gastrojournal.org/article/S0016-5085(13)00292-8/abstract Studies in animals have shown that changes in gut flora lead to changes in affective behaviors, so researchers wanted to determine whether similar results could be found in humans. The study, which was funded by Danone Research, used functional MRI to show that women who regularly consumed yogurt fortified with probiotics showed altered activity of brain regions that control central processing of emotion and sensation. Now, while it’s true that no one actually yet knows what the changes mean, the fact that they happen firmly establishes a gut-brain-axis in humans.

But this is hardly the first time that researchers have identified a possible relationship between our intestinal bacteria and our brains. There is an emerging concept of a gut bacteria–brain axis that suggests that it may be possible to treat complex central nervous system disorders by regulating intestinal bacteria…not, of course, naturally from the researchers POV, but medically.²² John F. Cryan,Timothy G. Dinan. “Mind-altering microorganisms: the impact of the gut microbiota on brain and behaviour.” Nature Reviews Neuroscience 13, 701-712 (October 2012). http://www.nature.com/nrn/journal/v13/n10/abs/nrn3346.html
And in fact, medical researchers are now proposing that medically supervised supplementation with probiotics might provide a viable therapy for relieving anxiety and even depression. fn] Logan AC, Katzman M. “Major depressive disorder: probiotics may be an adjuvant therapy.” Med Hypotheses. 2005;64(3):533-8.  http://www.ncbi.nlm.nih.gov/pubmed/15617861 [/fn]

And this may be just a hint of things to come.  Some studies suggest that probiotic supplementation may even improve memory.  For example, several recently published studies out of Iran support the idea that probiotics can help with better memory and the overall learning process. In one study, they gave probiotics to rats that are prone to diabetes and then tested their spatial memory as well as their ability to learn a maze. Those fed probiotics were better at both tasks.²³ Davari S, Talaei SA, Alaei H, Salami M. “The effect of co-administration of lactobacillus probiotics and bifidobacterium on spatial memory and learning in diabetic rats.” Tehran University Medical Journal 2012;70(9) : 531-539. http://journals.tums.ac.ir/abs.aspx?org_id=59&culture_var=en&journal_id=9&issue_id=2911&manuscript_id=22572&segment=fa In a second study published this year, they explored the mechanism of the gut-brain-axis that allows probiotics to influence memory and learning.²⁴ Davari S, Talaei SA, Alaei H, Salami M. “Probiotics treatment improves diabetes-induced impairment of synaptic activity and cognitive function: behavioral and electrophysiological proofs for microbiome-gut-brain axis.” Neuroscience. 2013 Jun 14;240:287-96. doi: 10.1016/j.neuroscience.2013.02.055. http://www.ncbi.nlm.nih.gov/pubmed/23500100 And a third study, published earlier this year, found that  whereas a Western diet negatively impacted mice in that it caused them to gain weight, impaired their spatial memory, and induced anxiety like behavior, the addition of probiotics to the diet prevented all these negative changes in the brain.²⁵ Ohland CL, Kish L, Bell H, Thiesen A, et al. “Effects of Lactobacillus helveticus on murine behavior are dependent on diet and genotype and correlate with alterations in the gut microbiome.” Psychoneuroendocrinology. 2013 Apr 5. pii: S0306-4530(13)00046-2. [Epub ahead of print]  http://www.ncbi.nlm.nih.gov/pubmed/23566632

Although the exact mechanism as to how intestinal bacteria impact cognition may not be known, the fact that they do so is becoming apparently obvious. Thus, we have every reason to try and maintain our intestinal microbiota in an optimized state of health…while waiting for the medical community to figure out a way to patent the process and charge more.

Conclusion: How to Optimize the Benefits of Probiotics

So, what we can take from all of this?

Well, first of all, we can pretty much say with some certainty, that despite the FDA’s reluctance to acknowledge it, the case for our intestinal microbiome being essential to our health is rapidly becoming overwhelming. And even more important, the case for supplementing with probiotics to improve that microbiome—and thus our health– is also becoming unarguable.

Second, it’s also now obvious, that nothing fancy is needed to accomplish this. You don’t need special enteric coated capsules or secret sauces or even patented strains to benefit from probiotics. Most of the studies cited above were based on administering fairly common strains of probiotics through food sources—the way mankind has done for thousands of years. The fact that these beneficial bacteria survive the stomach acid generated by the intake of food is now unarguable. How much easier, then, is it for them to survive if you take your probiotics as a supplement early in the morning or at night before bed when no food is in the stomach, and thus stomach acid is virtually non-existent?

Third, you want to supplement with a good mix of probiotics, as the studies show that different probiotics produce different benefits. No one strain, such as acidophilus, can do it all. Having a cup of commercial yogurt for lunch is not enough. Supplementing with a formula that contains superstrains of acidophilus, bifidus, thermophilus, salivarius, plantarum, and rhamnosus is probably a good place to start.  You’ll also want your formula to contain fructo-oligosaccharides (FOS) which help promote the growth of beneficial bacteria. For some of these bacteria, such as Bifidus, FOS can increase their effectiveness by a factor of 1,000 times or more!!

And be especially careful of those things that compromise your intestinal bacteria…that open the door to a state of dysbiosis.

• As I’ve said many times before, eating moderate amounts of organic, grassfed, meat is primarily an ethical decision, not a health decision. But eating more than 3-4 ounces a day of any kind of meat does become a health decision as it promotes the growth of E. coli in the intestinal tract at the expense of beneficial bacteria.
• And of course, drinking chlorinated water, or eating meats or dairy from animals fed a steady diet of antibiotics, totally defeats any program you’re on.
• And finally, if circumstances necessitate that you do undergo a round of antibiotics, always make sure to replenish your beneficial bacteria immediately upon completion of the antibiotics. Recolonize the good guys before the bad guys have a chance to take their place. Remember, nature abhors a vacuum. If you don’t supplement with good bacteria, bad bacteria will move in and populate throughout your intestinal tract, and you will suffer from dysbiosis.

The bottom line is that everyone wants to chase the newest and most exciting natural health ingredient when it appears. Remember how everything contained açaí or pomegranate for several years? And now if you attend a health show, those are so yesterday. The reality is, though, just because something like probiotics supplementation has been around for awhile or been overhyped in the media doesn’t negate its importance. When it comes to health and nutrition, newer isn’t always better. Do not think of probiotics as yesterday’s news or overhyped (even though they are). The simple fact is that taking care of your intestinal microbiome is one of the single most important things you can do for your health. Make a basic probiotic supplement, purchased from a company you trust, part of your everyday routine. Make no mistake; the benefits of probiotics are fundamental to your health. Don’t chase after probiotic gimmicks. If you decide to eat things like probiotic enhanced cereals, cookies, or candy, do it because you like the taste, not because you actually believe it will provide any benefit.