Do probiotics work? | Science Life

Do probiotics work? | Science Life.

From the 25 November 2014 University of Chicago press release

Walk past the dairy case or health food section of any grocery store and you’ll see a variety of yogurts, milk, shakes and even granola bars that say they contain probiotics. These “good” bacteria are added to foods to promote a healthy environment of microorganisms in the digestive tract, supposedly to aid in digestion and promote good gastrointestinal health. Are these claims based in real science, or are they just another food fad to squeeze money out of consumers?

We spoke to Stefano Guandalini, MD, Section Chief of Pediatric Gastroenterology, Hepatology, and Nutrition and Medical Director of the Celiac Disease Center at the University of Chicago, about probiotics and prebiotics, the precursor that provides fuel for the supposedly beneficial bacteria. He and his colleagues published a review paper recently looking at various studies and clinical trials that used pre- and probiotics to treat symptoms of inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) in children. The following is an edited version of that conversation.

Many people are familiar with the term probiotics, but what are prebiotics?

Prebiotics are basically the metabolic fuel for probiotics. It’s a term that encompasses a number of mostly carbohydrates that are present in vegetables and grains, for instance in wheat, artichokes, legumes, etc. They are only partially digested by the human intestinal tract, so they reach the colon where they are fermented by bacteria. We have trillions of bacteria happily living in our colon, and they ferment these substrates. They’re happy with them, and so they thrive. The idea of taking prebiotics is that you can encourage the growth of good bacteria in the gut by providing them the food they like.

Can you do that by changing your diet? Or is there a pill you can take?

You can do in both ways. If your diet is rich in things like onions, garlic, wheat, legumes and artichokes, then you ingest a lot of prebiotics already. But there are also chemically identifiable supplements that also serve the same purpose.

Are prebiotics effective for treating digestive diseases?

In theory these are a good way of promoting a healthy microflora in your gut, and one would expect beneficial effects, but in reality it has been quite disappointing. There’s not a lot of practical use for prebiotics as we speak, in terms of clinical effectiveness. The only niche in which we found them to be successful is as an additive to formula for premature babies, because human milk actually contains plenty of prebiotics. Other than that, there hasn’t been much practical use. In fact, in our review, we saw that prebiotics have been tried for treating irritable bowel syndrome, but actually with mostly negative results.

With inflammatory bowel disease, it’s likely different. Several preparations have been tried with mixed results, but again, nothing sticks out as important or with clinical relevance. So in spite of good conceptual reasons to expect good results, they have not been proven very effective.

How are probiotics different from prebiotics?

Probiotics are microorganisms that, if ingested in adequate amounts, confer a health benefit to the host beyond the nutritional value. In practical terms, it’s a class of mostly live bacteria that have been studied for a long time and found useful for treating or preventing a number of clinical conditions.

Our review paper focuses on the efficacy of probiotics for IBS and IBD, including both ulcerative colitis and Crohn’s disease. For IBS, we have some good evidence in adults that some probiotics actually seem to be effective in relieving some of the symptoms, mostly the bloating and abdominal pain that accompanies IBS, especially when there is either diarrhea or constipation that goes along with it.

And in the case of ulcerative colitis, there is a growing body of evidence supporting the efficacy of some specific strains as an adjuvant in the course of the therapy. Crohn’s disease is different, however. People have tried multiple ways of addressing the problem with different strains of probiotics, different clinical settings, different endpoints, but none of the researchers were able to show any efficacy with probiotics in Crohn’s disease patients.

You can go into any grocery store and find yogurt and other foods that have probiotics added to them. Do those products do any good?

Not all probiotics are equal, that’s an important thing to stress. People think they can walk into a store and pick any probiotic from the shelf and they’re just the same. That is not the case. Different probiotics have different strains and concentrations of bacteria that have different properties. Only a minority of them has been tested properly in clinical trials to find if they were indeed effective.

In reality, yogurt by definition has to have two strains of bacteria—Lactobacillus bulgaricus andStreptococcus thermophilus—to create the yogurt. However these strains do not pass the gastrointestinal tract intact. They are destroyed by the acidity of the stomach and the enzymes of the pancreas, so nothing reaches the colon and it’s not beneficial. However, like you said, some yogurts are now enriched with other live bacteria of different strains. Some of them indeed include strains that survive the passage through the intestinal tract and then can be beneficial, and some make that claim but they don’t, and it’s hard for the general public to discriminate. Activia, for instance, is one of the good preparations. These yogurts actually do have strains of live Bifidobacteria that have been studied and may be beneficial. Yakult, containing well-studied strains of Lactobacilli, is another one that does the same.

Is a food product the best way to treat symptoms of IBS or IBD, or do you need a special preparation in a pill?

The best way is to use specific strains that have been validated through clinical trials and published in peer-reviewed journals to show efficacy, and if possible reproduced by different groups using the same preparations. So the list of probiotics that have gone through this process is actually very short:

• There is a product called Align, based on a specific Bifidobacterium, which is mostly for adults with IBS.
• For infants and colicky babies there is some proof of effectiveness for a product called Biogaia, which has the bacterium Lactobacillus reuteri in it.
• Then we have Culturelle with Lactobacillus GG, another one with a long record of scientific, well conducted studies, which has been found effective in treating diarrheal diseases.
• Florastor, which contains a yeast [Saccharomyces boulardii] instead of bacteria, is also effective in treating and preventing antibiotic associated diarrhea. Children who get antibiotics often develop diarrhea, and in many cases that can be prevented by the use of Florastor.
• Finally there is a preparation called VSL #3, which is a highly concentrated preparation of 8 different strains of probiotics. This has received a great deal of attention by the scientific world to treat a number of conditions. It seems to be effective for ulcerative colitis, both in adults and children, and it has been found effective in irritable bowel syndrome as well.

Outside of this incredibly short list, however, there is nothing else. There is no other probiotic that has been found to be effective in rigorous, controlled clinical trials. This is not to say they aren’t working, it’s just to say we don’t have any scientific proof yet.

Are probiotics safe?

One thing that all these probiotics have in common is that they are relatively safe. They are very tolerable and basically create no side effects. One caveat is for premature babies and people with profoundly depressed immune systems. Some of these preparations might be contaminated by yeasts, which can be dangerous in those cases. But with these two exceptions, probiotics have been used in large amounts for generations now. So they are safe, but if there is no clear cut indication, I wouldn’t necessarily recommend them. That’s a question I often get from patients, “Could we use probiotics?” And if it’s not to treat a specific condition and they just think it will improve health, I tell them it’s not necessary.

Where is the research on prebiotics and probiotics headed?

It’s interesting. There was a boom for years and then it died down quite a bit. From a laboratory standpoint, we don’t understand a lot about how the probiotics work. So I think the attention of scientists now is more focused on understanding the mechanisms of the interactions between these bacteria and the host, which are different between different individuals. Each one of us has a unique composition of intestinal flora. The same probiotics may have a different effect for you and me, because they interact with trillions of other bacteria, which are different for each person. So all of these nuances are going back to basic science before moving further to the clinical arena.

That seems to be a theme of microbiome research. Everyone agrees on its profound effect on our health, but getting to where you could change something meaningfully to treat a disease is a different thing.

Right, we are not there yet. It’s very complicated. As we have said many times, the genome of the microbes is thousands of times more complex and more numerous than the human genome. When we are talking about personalized medicine, we are really talking about the microbiome: how to understand all the subtle interactions with the human host, and how to possibly exploit this for health reasons. It’s an incredibly interesting area, and my colleagues here at the University of Chicago,David Rubin, Eugene Chang, Cathryn Nagler, Bana Jabri and others are actively working on this. We aren’t there yet, but we will. I have great enthusiasm in this. I think this is the medicine of the future.

[Magazine article] Sorry, Your Gut Bacteria Are Not the Answer to All Your Health Problems | Mother Jones

 

Sorry, Your Gut Bacteria Are Not the Answer to All Your Health Problems | Mother Jones.

Excerpts

In 2001, Joshua Lederberg, a Nobel Prize-winning biologist, coined the term “microbiome,” naming the trillions of microorganisms that reside in and on our bodies. Today, if you type that word into Google, you’ll turn up thousands of hits linking gut bacteria to a laundry list of health problems, from food allergies to Ebola. Between 2007 and 2012, the number of journal articles published on the microbiome increased by nearly 250 percent. Our bodily inhabitants are quickly being cast as culprits or saviors for a diverse array of ailments.

…

Still, despite the optimism, some researchers caution that much of what we hear about microbiome science isn’t always, well, science. Dr. Lita Proctor heads the National Institutes of Health (NIH) Human Microbiome Project (HMP), an outgrowth of the Human Genome Project. “We are discovering a whole new ecosystem,” she says. But “I do have some fear—we all do in the field—that the hype and the potential overpromise, and the idea that somehow this is going to be different—there is a terrific fear that it will all backfire.”

…

he goal of the first phase of the HMP was to identify the microbial makeup of a “healthy” microbiome. And, in a study published earlier this year, researchers made an important discovery—that there is no such thing. Even among people who were examined and found to be perfectly healthy, each person’s microbiome was unique.

“We were going about it all wrong,” Proctor explains. “It is not the makeup—these communities come together and they actually become bigger than the sum of their parts…It almost doesn’t matter who is present, it just matters what they are doing.”

Jonathan Eisen, a professor and biologist who studies the ecology of microbes at the University of California-Davis, shares Proctor’s concerns. In a series on his blog called “The Overselling the Microbiome Awards,” Eisen highlights what he considers to be skewed science. He has taken on transplants purported to treat multiple sclerosis, celiac disease, and Crohn’s disease. He casts doubt on a study claiming there’s a connection between a mother’s oral hygiene during pregnancy to the health of her newborn. He critiques the notion that you can use bacteria to battle breast cancer, prevent stroke, and cure Alzheimer’s.

Eisen says that one of the most common errors in studies is confusion between correlation and causation. [My emphasis!]  “The microbiome has 400 million different variables that you can measure about it,” Eisen explains. “The different sites, the different species, the relative abundance of those species, the variation—if you have that many variables, I can guarantee statistically that some of them will be perfectly correlated with Crohn’s disease and have nothing to do with it.”

Oral Probiotics: An Introduction

From the article at the US National Center for Complementary and Alternative Medicine (NCCAM)

Introduction

Probiotics are live microorganisms (e.g., bacteria) that are either the same as or similar to microorganisms found naturally in the human body and may be beneficial to health. Also referred to as “good bacteria” or “helpful bacteria,” probiotics are available to consumers in oral products such as dietary supplements and yogurts, as well as other products such as suppositories and creams. The U.S. Food and Drug Administration (FDA) has not approved any health claims for probiotics. This fact sheet provides a general overview of probiotics, with an emphasis on oral products, and suggests sources for additional information.

 

Key Points

• Although some probiotic formulations have shown promise in research, strong scientific evidence to support specific uses of probiotics for most conditions is lacking.
• Studies suggest that probiotics usually have few side effects. However, the data on safety, particularly long-term safety, are limited, and the risk of serious side effects may be greater in people who have underlying health conditions.
• If you are considering a probiotic dietary supplement, consult your health care provider first. Do not replace scientifically proven treatments with unproven products or practices.
• Tell all your health care providers about any complementary health approaches you use. Give them a full picture of what you do to manage your health. This will help ensure coordinated and safe care.

 

Probiotics, Prebiotics, and Synbiotics

Probiotics are not the same as prebiotics—nondigestible substances that stimulate the growth and/or activity of potentially beneficial microorganisms. The term “synbiotics” refers to products that combine probiotics and prebiotics.

About Probiotics

The concept behind probiotics was introduced in the early 20th century, when Nobel laureate Elie Metchnikoff, known as the “father of probiotics,” proposed in The Prolongation of Life: Optimistic Studiesthat ingesting microorganisms could have substantial health benefits for humans. Microorganisms are invisible to the naked eye and exist virtually everywhere. Scientists continued to investigate the concept, and the term “probiotics”—meaning “for life”—eventually came into use.

Picturing the human body as a “host” for bacteria and other microorganisms is helpful in understanding probiotics. The body, especially the lower gastrointestinal tract (the gut), contains a complex and diverse community of bacteria. (In the body of a healthy adult, cells of microorganisms are estimated to outnumber human cells by a factor of ten to one.) Although we tend to think of bacteria as harmful “germs,” many bacteria actually help the body function properly. Most probiotics are bacteria similar to the beneficial bacteria found naturally in the human gut.

Various mechanisms may account for the effects of probiotics on human health. Possible mechanisms include altering the intestinal “microecology” (e.g., reducing harmful organisms in the intestine), producing antimicrobial compounds (substances that destroy or suppress the growth of microorganisms), and stimulating the body’s immune response.

Probiotics commonly used in the United States include Lactobacillus and Bifidobacterium. There are many specific types of bacteria within each of these two broad groups, and health benefits associated with one type may not hold true for others.

 

Government Regulation of Probiotics

Government regulation of probiotics is complex. Depending on a probiotic product’s intended use, the FDA might regulate it as a dietary supplement, a food ingredient, or a drug. Many probiotic products are sold as dietary supplements, which do not require FDA approval prior to marketing. Dietary supplement labels may make claims about how the product affects the structure or function of the body without prior FDA approval, but they cannot make health claims (claims that the product reduces the risk of a disease) without the FDA’s consent. (For more information about dietary supplements, seeUsing Dietary Supplements Wisely.) A product that is marketed as a drug must meet more stringent requirements. It must be proven safe and effective for its intended use through clinical studies (tests in people) and be approved by the FDA before it can be marketed.

Use of Probiotics in the United States

In the United States, probiotics are available as dietary supplements (including capsules, tablets, and powders) and in dairy foods (such as yogurts with live active cultures). According to the 2007 National Health Interview Survey, which included a comprehensive survey on the use of complementary health approaches by Americans, “prebiotics/probiotics” ranked fifth among natural products used for children, but were not among the top-ranking products for adults. Although probiotic products are more popular in Europe and Japan than in the United States, the U.S. consumer market for probiotics is growing rapidly.

Although the FDA has not approved any health claims for probiotics, they are used for a variety of gastrointestinal conditions such as infectious diarrhea, diarrhea associated with using antibiotics, irritable bowel syndrome, and inflammatory bowel disease (e.g., ulcerative colitis and Crohn’s disease). Probiotics are also being used for preventing tooth decay and for preventing or treating other oral health problems such as gingivitis and periodontitis. Some—but not all—probiotic formulations have been widely studied and show considerable promise. However, the rapid growth in marketing and consumer interest and use has outpaced scientific research on the safety and efficacy of probiotics for specific health applications.

 

What the Science Says

The potential of probiotics to benefit human health in many different ways has stimulated great interest and activity among researchers. For example, the National Center for Complementary and Alternative Medicine (NCCAM) is part of the National Institutes of Health (NIH) Probiotic and Prebiotic Working Group, a trans-NIH effort to identify gaps and challenges in prebiotic/probiotic research.

Probiotic research is moving forward on two fronts: basic science (laboratory studies) and clinical trials to evaluate the safety and efficacy of probiotics for various medical conditions. Many early clinical trials of probiotics have had methodological limitations, and definitive clinical evidence to support using specific probiotic strains for specific health purposes is generally lacking. Nevertheless, there is preliminary evidence for several uses of probiotics, and more studies are under way. In particular, a recent review of the scientific evidence on the effectiveness of probiotics in acute infectious diarrhea concluded that there was evidence that probiotics may shorten the duration of diarrhea and reduce stool frequency but that more research was needed to establish exactly which probiotics should be used for which groups of people.

In 2008, the journal Clinical Infectious Diseases published a special issue on probiotics, which included an overview of clinical applications. Based on a review of selected studies, the authors classified several applications according to the strength of evidence supporting the efficacy of probiotics in prevention and/or treatment. For example, the authors concluded that strong evidence exists for acute diarrhea and antibiotic-associated diarrhea, and substantial evidence exists for atopic eczema (a skin condition most commonly seen in infants). Promising applications include childhood respiratory infections, tooth decay, nasal pathogens (bacteria harbored in the nose), gastroenteritis relapses caused by Clostridium difficilebacteria after antibiotic therapy, and inflammatory bowel disease. The authors also discussed various potential future applications.

Studies also indicate that probiotics may reduce side effects associated with treatment for Helicobacter pylori infection, the cause of most stomach ulcers. A systematic review suggests that there is strong evidence that probiotics may reduce the risk of necrotizing enterocolitis, a severe intestinal condition of premature newborns. Other potential future applications include use in reducing cholesterol levels, treating obesity, and managing irritable bowel syndrome.

 

Safety and Side Effects

It appears that most people do not experience side effects from probiotics or have only mild gastrointestinal side effects such as gas. But there have been some case reports of serious adverse effects, and research on safety is ongoing. A 2008 review of probiotics safety noted that Lactobacillus rhamnosus GG has been widely studied in clinical trials for a variety of conditions and generally found to be safe. Nevertheless, a recent review of Lactobacillus and Bifidobacterium noted that the long-term, cumulative effects of probiotics use, especially in children, are unknown, and also pointed to evidence that probiotics should not be used in critically ill patients. Similarly, a 2011 Agency for Healthcare Research and Quality assessment of the safety of probiotics, partly funded by NCCAM, concluded that the current evidence does not suggest a widespread risk of negative side effects associated with probiotics. However, the data on safety, particularly long-term safety, are limited, and the risk of serious side effects may be greater in people who have underlying health conditions.

Concerns have also been raised about the quality of probiotic products. Some products have been found to contain smaller numbers of live microorganisms than expected. In addition, some products have been found to contain bacterial strains other than those listed as ingredients.

 

Saccharomyces boulardi (large cells) found along with bacteria in fermented fruit juice.
Photo Credit: SciMAT / Photo Researchers, Inc

If You Are Considering Probiotics

• Our understanding of probiotics is a work in progress. Although probiotic products are marketed for many different uses, scientific evidence supporting specific uses is still limited, and the FDA has not approved any health claims for probiotics. Before using probiotics, learn as much as you can by talking to your health care provider and researching reliable sources of information.
• Probiotic products may contain different types of probiotic bacteria and have different effects in the human body. The effects also may vary from person to person.
• Do not replace scientifically proven treatments with unproven products and practices. Do not use a complementary health product, such as probiotics, as a reason to postpone seeing your health care provider about any health problem.
• If you are pregnant or nursing a child, or if you considering giving a child a dietary supplement, such as probiotics, it is especially important to consult your (or your child’s) health care provider.
• Anyone with a serious underlying health problem should be monitored closely for potential negative side effects while taking probiotics.
• Tell all your health care providers about any complementary health approaches you use. Give them a full picture of what you do to manage your health. This will help ensure coordinated and safe care. For tips on talking with your health care providers about complementary health approaches, seeNCCAM’s Time to Talk campaign.

 

Scanning electron micrograph (SEM) of Bifidobacterium bifidum.
Photo Credit: SciMAT/Photo Researchers, Inc

NCCAM-Funded Research on Probiotics

Recent NCCAM-supported research on probiotics has included clinical studies¹ focused on:

• Diarrhea in infants
• Irritable bowel syndrome and minimal hepatic encephalopathy (a complication of liver disease)
• An antibiotic-resistant type of bacteria

• Yogurt beverages as a way of giving high doses of probiotics to young children.

NCCAM also supports laboratory studies that explore possible mechanisms of action for probiotics, providing a foundation for clinical research. For example, recent studies have found evidence that a strain of Lactobacillus reuteri might slow the growth of certain tumors, and that Lactobacillus acidophilusmight enhance the effects of a vaccine against rotavirus infection—the most common cause of infectious diarrhea in infants and children worldwide.

NCCAM’s clinical research program has designated probiotics as a high-priority topic for upcoming projects. Studies will focus on probiotics for addressing gastrointestinal disorders in infants and children, including necrotizing enterocolitis, colic, and irritable bowel syndrome; treating and preventing antibiotic-induced diarrhea; and enhancing the effects of flu vaccine.

1. NCCAM-supported clinical research includes studies conducted under FDA-approved investigational new drug applications. Before these studies can proceed to medically vulnerable populations, researchers carry out rigorous trials to determine safety in healthy adults or people with mild medical conditions.

Color enhanced scanning electron micrograph (SEM) of the bacteria Lactobacillus acidophilus. A spirochete bacteria can also be seen at center.
Photo Credit: SciMAT/Photo Researchers, Inc

Key References

• AlFaleh KM, Bassler D. Probiotics for prevention of necrotizing enterocolitis in preterm infants.Cochrane Database of Systematic Reviews. 2008;(1):CD005496. Accessed atwww.thecochranelibrary.com on February 15, 2011.
• Allen SJ, Martinez EG, Gregorio GV, et al. Probiotics for treating acute infectious diarrhoea. Cochrane Database of Systematic Reviews. 2010;(11):CD003048. Accessed at www.thecochranelibrary.comon February 15, 2011.
• American Academy of Microbiology. Probiotic Microbes: The Scientific Basis. Report from a colloquium held in Baltimore, MD, November 5–7, 2005. Washington, DC: American Academy of Microbiology; 2006.
• Bonifait L, Chandad F, Grenier D. Probiotics for oral health: myth or reality? Journal (Canadian Dental Association). 2009;75(8):585–590.
• Drisko J, Bischoff B, Giles C, et al. Evaluation of five probiotic products for label claims by DNA extraction and polymerase chain reaction analysis. Digestive Diseases and Sciences. 2005;50(6):1113–1117.
• Duffy LC, Sporn S, Hibberd P, et al. Lactobacilli and Bifidobacteria. In: Coates PM, Betz JM, Blackman MR, et al., eds. Encyclopedia of Dietary Supplements. 2nd ed. New York, NY: Informa Healthcare; 2010:469–478.
• Food and Agriculture Organization (FAO) of the United Nations and World Health Organization (WHO).Guidelines for the Evaluation of Probiotics in Food. Report of a Joint FAO/WHO Working Group on Drafting Guidelines for the Evaluation of Probiotics in Food, London, Ontario, Canada, April 30-May 1, 2002. Accessed at ftp://ftp.fao.org/es/esn/food/wgreport2.pdf on January 26, 2010.
• Goldin BR, Gorbach SL. Clinical indications for probiotics: an overview. Clinical Infectious Diseases. 2008;46(suppl 2):S96–S100.
• Hempel S, Newberry S, Ruelaz A, et al. Safety of Probiotics to Reduce Risk and Prevent or Treat Disease. Evidence Report/Technology Assessment no. 200. Agency for Healthcare Research and Quality Web site. Accessed at www.ahrq.gov/clinic/tp/probiotictp.htm on May 10, 2011.
• Hibberd PL, Hoffman FA, Heimbach JT, eds. Developing probiotics as food and drugs: scientific and regulatory challenges. Clinical Infectious Diseases. 2008;46(suppl 2).
• Hoffman FA, Heimbach JT, Sanders ME, et al. Executive summary: scientific and regulatory challenges of development of probiotics as foods and drugs. Clinical Infectious Diseases. 2008;46(suppl 2):S53–S57.
• Iyer C, Kosters A, Sethi G, et al. Probiotic Lactobacillus reuteri promotes TNF-induced apoptosis in human myeloid leukemia-derived cells by modulation of NF-kB and MAPK signaling. Cellular Microbiology. 2008;10(7):1442–1452.
• Kligler B, Cohrssen A. Probiotics. American Family Physician. 2008;78(9):1073–1078.
• McDade-Ngutter C, Versalovic J, Alexander W, et al. National Institutes of Health Gastrointestinal Microbiota and Advances in Prebiotic and Probiotic Research conference summary.Gastroenterology. 2009;136(5):1473–1475.
• Neish AS. Microbes in gastrointestinal health and disease. Gastroenterology. 2009;136(1):65–80.
• Petrof EO. Probiotics and gastrointestinal disease: clinical evidence and basic science. Anti-Inflammatory and Anti-Allergy Agents in Medicinal Chemistry. 2009;8(3):260–269.
• Preidis GA, Versalovic J. Targeting the human microbiome with antibiotics, probiotics, and prebiotics: gastroenterology enters the metagenomics era. Gastroenterology. 2009;136(6):2015–2031.
• Sethi T. Probiotics in pediatric care. Explore. 2009;5(4):245–249).
• Sharp RR, Achkar JP, Brinich MA, et al. Helping patients make informed choices about probiotics: a need for research. American Journal of Gastroenterology. 2009;104(4):809–813.
• Snydman DR. The safety of probiotics. Clinical Infectious Diseases. 2008;46(suppl 2):S104–S111).
• Tong JL, Ran ZH, Shen J, et al. Meta-analysis: the effect of supplementation with probiotics on eradication rates and adverse events during Helicobacter pylori eradication therapy. Alimentary Pharmacology and Therapeutics. 2007;25(2):155–168.
• Vanderhoof JA, Young R. Probiotics in the United States. Clinical Infectious Diseases. 2008;46(suppl 2):S67–S72.
• Zhang W, Azevedo MSP, Wen K, et al. Probiotic Lactobacillus acidophilus enhances the immunogenicity of an oral rotavirus vaccine in gnotobiotic pigs. Vaccine. 2008;26(29–30):3655–3661.

Top

For More Information

NCCAM Clearinghouse

The NCCAM Clearinghouse provides information on NCCAM and complementary health approaches, including publications and searches of Federal databases of scientific and medical literature. The Clearinghouse does not provide medical advice, treatment recommendations, or referrals to practitioners.

Toll-free in the U.S.:

1-888-644-6226

TTY (for deaf and hard-of-hearing callers):

1-866-464-3615

Web site:

nccam.nih.gov

E-mail:

info@nccam.nih.gov

PubMed®

A service of the National Library of Medicine (NLM), PubMed® contains publication information and (in most cases) brief summaries of articles from scientific and medical journals.

Web site:

www.ncbi.nlm.nih.gov/pubmed

Acknowledgments

NCCAM thanks the following people for their technical expertise and review of the content update of this publication: Patricia Hibberd, M.D., Ph.D., Massachusetts General Hospital for Children; Marguerite Klein, M.S., NIH Office of Dietary Supplements; and Linda Duffy, Ph.D., and John (Jack) Killen, Jr., M.D., NCCAM.

This publication is not copyrighted and is in the public domain. Duplication is encouraged.

NCCAM has provided this material for your information. It is not intended to substitute for the medical expertise and advice of your primary health care provider. We encourage you to discuss any decisions about treatment or care with your health care provider. The mention of any product, service, or therapy is not an endorsement by NCCAM.

* Note: PDF files require a viewer such as the free Adobe Reader.

NCCAM Pub No.:

D345

Date Created:

January 2007

Last Updated:

December 2012

Related articles

• Experts: Probiotics may help keep your gut happy (redding.com)
• If you have to take an antibiotic, should you take a probiotic, too? (boingboing.net)
• I’ve been prescribed an antibiotic. Should I take a probiotic? (sciencebasedmedicine.org)
• Experts: Probiotics may help keep your gut happy (reporternews.com)
• MEDICAL CORNER …. Good bacteria wanted!! (hrexach.wordpress.com)

Beneficial Bacteria May Help Ward Off Infection

 

English: Template for Template:Food safety (Photo credit: Wikipedia)

 

From the 19 July 2012 article at Science News Daily

 

While many bacteria exist as aggressive pathogens, causing diseases ranging from tuberculosis and cholera, to plague, diphtheria and toxic shock syndrome, others play a less malevolent role and some are critical for human health.

In a new study, Cheryl Nickerson and her group at ASU’s Biodesign Institute, in collaboration with an international team including Tom Van de Wiele and lead author Rosemarie De Weirdt at Ghent University, Belgium, explore the role of Lactobaccilus reuteri — a natural resident of the human gut — to protect against foodborne infection.

Their results demonstrate that this beneficial or probiotic organism, which produces an antimicrobial substance known as reuterin, may protect intestinal epithelial cells from infection by the foodborne bacterial pathogen Salmonella….

…

Bacterial Blizzard

A swarm of some hundred trillion bacteria occupies the human body, outnumbering human cells by about 10 to 1. Among these are members of the genus Lactobacilli, some of which have been associated with therapeutic, probiotic properties, including anti-inflammatory and anti-cancer activity.

The current study zeros in on Lactobacillus reuteri — one of the more than 180 species of Lactobacilli. The group investigated the potential of this bacterium to inhibit the early stages ofSalmonella infection, seeking to identify plausible mechanisms for such inhibitory effects.

Intestinal infections by non-typhoidal Salmonella strains induce diarrhea and gastroenteritis, and remain a leading source of foodborne illness worldwide. Such infections are acutely unpleasant but self-limiting in healthy individuals. For those with compromised immunity however, they can be deadly and the alarming incidence of multi-drug resistant Salmonellastrains has underlined the necessity of more effective therapeutics.

The use of benign microorganisms offers a promising new approach to treating infection from pathogens like Salmonellaand indeed, L. reuteri has been shown to help protect against gastrointestinal infection and reduce diarrhea in children.

Safeguarding cells

The origin of L. reuteri’s protective role still remains unclear, and the present study investigated whether reuterin, a metabolite produced by L. reuteri during the process of reducing glycerol in the gut, could be one of the keys to protection. While it has been speculated that reuterin acts by regulating immune responses or competing with Salmonella for key binding sites, the current study represents the first in vitro examination of host-pathogen interactions using human intestinal epithelium in the presence of reuterin-producing L. reuteri.

 

Related articles

• Probiotics (slideshare.net)
• Genome Project for Food Pathogens Launched by FDA (bespacific.com)
• Tummy Troubles, Colic, and Mama’s Diet (scienceofmom.com)
• FDA plans database for identifying foodborne germs (sfgate.com)
• Genome Project for Food Pathogens Launched (fda.gov)
• Toward an alternative for antibiotics to fight bacterial infections? (eurekalert.org)
• Seeking An Alternative For Antibiotics To Fight Bacterial Infections (medicalnewstoday.com)
• The Surprising Viruses in Our Gut [The Weizmann Wave] (scienceblogs.com)

 

Probiotics reduce infections for patients in intensive care, study finds

 Probiotics reduce infections for patients in intensive care, study finds

From the Science Daily article of Thu Dec 1, 2011

Traumatic brain injury is associated with a profound suppression of the patient’s ability to fight infection. At the same time the patient also often suffers hyper-inflammation, due to the brain releasing glucocorticoids. New research shows that including probiotics with nutrients, supplied via the patient’s feeding tube, increased interferon levels, reduced the number of infections, and even reduced the amount of time patients spent in intensive care.

A gut-full of probiotics for your neurological well-being

From the 5 July 2011 Science Daily article

Probiotics, often referred to as ‘good bacteria’, are known to promote a healthy gut, but can they promote a healthy mind? Exploring the new world of neurological probiotics, researchers in BioEssays present new ideas on how neurochemicals delivered directly to the gut, via probiotic intestinal microbiota, exert their beneficial effects in maintaining gastrointestinal health and even psychological well-being.
The research, led by Professor Mark Lyte from Texas Tech University Health Sciences Center, proposes that through a unifying process of microbial endocrinology, neurochemical-producing probiotics could act as a delivery mechanism for neuroactive compounds that could improve a host’s gastrointestinal and psychological health.
“This paper proposes a new field of microbial endocrinology, where microbiology meets neuroscience,” said Lyte. “There is already evidence to suggest that the connection between gut microbes and the nervous system represents a viable route for influencing neurological function. A recent study in mice, for example, showed that the presence of neurochemicals such a serotonin in the bloodstream was due to direct uptake from the gut.”
In his hypothesis Professor Lyte considers the selection of probiotics, such as lactobacilli and bifidobacteria, and how the active uptake of neurochemicals, generated by bacteria in the gut and circulated through a patient’s bloodstream, represents a pathway for probiotics to exert extra-intestinal effects including behavioral changes.

 

A link to the abstract of the research article may be found here.
Access to the full text of the article requires a subscription.
Click here for suggestions on how to get this article for free or at low cost. 

Related articles

• Probiotics for Kids (everydayhealth.com)
• Should I Take Probiotics? (everydayhealth.com)
• Safety of Probiotics Used to Reduce Risk and Prevent or Treat Disease (jflahiff.wordpress.com)

Safety of Probiotics Used to Reduce Risk and Prevent or Treat Disease

The US Agency for Healthcare Research and Quality has recently released a report on the safety of probiotics to prevent and treat diseases.

From their press release

Objectives: To catalog what is known about the safety of interventions containing Lactobacillus, Bifidobacterium, Saccharomyces, Streptococcus, Enterococcus, and/or Bacillus strains used as probiotic agents in research to reduce the risk of, prevent, or treat disease.

Data Sources: We searched 12 electronic databases, references of included studies, and pertinent reviews for studies addressing the safety of probiotics from database inception to August 2010 without language restriction.

Review Methods: We identified intervention studies on probiotics that reported the presence or absence of adverse health outcomes in human participants, without restriction by study design, participant type, or clinical field. We investigated the quantity, quality, and nature of adverse events.

Results: The search identified 11,977 publications, of which 622 studies were included in the review. In 235 studies, only nonspecific safety statements were made (“well tolerated”); the remaining 387 studies reported the presence or absence of specific adverse events. Interventions and adverse events were poorly documented.

A number of case studies described fungemia and some bacteremia potentially associated with administered probiotic organisms. Controlled trials did not monitor routinely for such infections and primarily reported on gastrointestinal adverse events. Based on reported adverse events, randomized controlled trials (RCTs) showed no statistically significantly increased relative risk (RR) of the overall number of experienced adverse events (RR 1.00; 95% confidence interval [CI]: 0.93, 1.07, p=0.999); gastrointestinal; infections; or other adverse events, including serious adverse events (RR 1.06; 95% CI: 0.97, 1.16;p=0.201), associated with short-term probiotic use compared to control group participants; long-term effects are largely unknown. Existing studies primarily examined Lactobacillus alone or in combination with other genera, often Bifidobacterium.

Few studies directly compared the safety among different intervention or participant characteristics. Indirect comparisons indicated that effects of delivery vehicles (e.g., yogurt, dairy) should be investigated further. Case studies suggested that participants with compromised health are most likely to experience adverse events associated with probiotics. However, RCTs in medium-risk and critically ill participants did not report a statistically significantly increased risk of adverse events compared to control group participants.

Conclusions: There is a lack of assessment and systematic reporting of adverse events in probiotic intervention studies, and interventions are poorly documented. The available evidence in RCTs does not indicate an increased risk; however, rare adverse events are difficult to assess, and despite the substantial number of publications, the current literature is not well equipped to answer questions on the safety of probiotic interventions with confidence.

---

Download Report

Safety of Probiotics Used to Reduce Risk and Prevent or Treat Disease

• Executive Summary (Publication No. 11-E007-1)
• Evidence Report (Publication No. 11-E007-EF): (PDF File, 8.4 MB) PDF Help

Evidence-based Practice Center: RAND-Southern California
Topic Nominators: National Institutes of Health (NIH) Office of Dietary Supplements; NIH National Center for Complementary and Alternative Medicine; Food and Drug Administration, Center for Food Safety and Applied Nutrition

Current as of April 2011

---

Related articles

• Probiotics: New Hope for People with Celiac Disease (glutenfreemommyandme.com)
• Gut bacteria can control organ functions (jflahiff.wordpress.com)
• Health Tip: Should You Take Probiotics? (jflahiff.wordpress.com)

• Probiotic identified to treat ulcers (eurekalert.org)
• New Treatment for Urinary Tract Infections Called Promising (nlm.nih.gov)
• Probiotic bacteria could help treat Crohn’s disease (physorg.com)

Health Tip: Should You Take Probiotics?

From an October 20th Health Day news item

By Diana Kohnle

(HealthDay News) — Probiotics are micro-organisms designed to help manage digestive health. Manufacturers are now including them in everything from yogurt to granola bars, the American Gastroenterological Association says.

[Probiotics: What They Are and What They Can Do for You]

While studies have shown that probiotics may help people with a host of digestive conditions, their benefit hasn’t been proven in people with severely compromised immune systems, the association says.

On the other hand, probiotics may help treat people with:

• Irritable bowel syndrome (IBS).
• Inflammatory bowel disease (IBD).
• Diarrhea caused by infection with a virus, bacteria or parasite.
• Diarrhea caused by taking antibiotics.

 

HealthDay
 

 

Complementary and Alternative Medicine: Focus on Research and Care

[From http://nccam.nih.gov/news/newsletter/2010_may/naturalproduct.htm ]

 

In a recent US government newsletter, recent studies on the benefits of fish oil, cranberry juice, and probiotics were highlighted.

Research funded by the US National Center for Complementary and Alternative Medicine enables scientists to study the effects of many natural and complementary medicine products and substances. Omega‑3 supplementation in studies lasting at least a year seem to be beneficial in reducing risk for only specific heart ailments  (as recent heart attack)and thus cardiovascular deaths and overall mortality. 

Recent intermediary level trials involving humans seem to suggest cranberry reduces infections through removing available iron in a person’s body that bacteria needs to live. Also, probiotics (which are living microorganisms living in the human body that may confer health benefits) may prove useful in reducing or preventing gastrointestinal illnesses as diarrhea.