The human body contains approximately 37 trillion cells. If you find this fact astounding you will find this one super astounding… bacteria in the human body outnumber cells 10 to 1. Most of these bacteria call the gut home.
Indeed it was Hippocrates who said, “All disease begins in the gut.” We would be wise heed this proclamation when if we desire good health and longevity.
Create this mental picture if you will. The gut is a playing field, on one side you have the good bacteria and on the other, you have the bad bacteria - evil vs good to the max. Second, by second, there is a battle going on in your gut. When the good guys come out on top you may experience great health and a strong defense from the onset of sickness and disease. When the bad guys are winning, conditions are ripe for sickness and disease to develop. It is imperative to have the right kind and amount of bacteria not only for protection from sickness and disease but also for the wide array of health benefits they bring.
Humans have been eating bacteria for thousands of years
Humans have been eating “living foods” teaming with healthy bacteria for a very long time. Fermented foods such as kombucha, miso, kimchi, tempeh,natto, and buttermilk provide a variety of bacteria that are beneficial for gut health and overall wellbeing. However, with the industrial food revolution, these and other raw foods were quickly replaced with imposters that would last longer and taste better (say some). Easy food, some call it. However, this so-called revolution has had, without question, the most detrimental impact on human health in the entire history of mankind. Food refining brings toxins, sugar, processed oils and a host of other “dead” ingredients, additives, flavorings and artificial colorings that make the food manufacturers rich and leave consumers sick.
Can probiotics make us well again?
One popular way to sustain and regain health, embraced today by millions, is to consume probiotics. Touted by alternative health practitioners to mainstream medical doctors, probiotics are said to improve digestion, boost the immune system and even elevate moods. But are they actually a good replacement for the living foods of the past?
What exactly are probiotics?
Probiotics are live microorganisms that come from food or supplements and when consumed in adequate amounts can benefit the host. (1)
Probiotics are not without question
Although there is much anecdotal and plenty of scientific research pointing to the benefits of probiotics for many health conditions. (2) there are also those, however, who challenge the effectiveness of probiotics, especially ones found in supermarkets or infused in foods. Many of these are products that have very little scientific backing behind them.
This has not stopped the probiotic industry from exploding. There are probiotics for almost every condition possible, sold in a variety of forms including pills, capsules, gummies, and powders. There are probiotics for men, for women, for kids and even for pets. On top of this, there are all sorts of food items that claim to contain probiotics. The global probiotics industry is expected to grow to $52 billion by 2020, according to Grand View Research. (3)
A 2012 study reveals that 3.9 million Americans take probiotics regularly and eat them in all sorts of foods including yogurt and smoothies. In addition, almost 61% of doctors prescribe probiotics on a regular basis to their patients. (4)
The study of gut health and probiotics is not new
The study of gut health and probiotics is not new. In 1908 scientist Elie Metchnikoff, known as “the father of natural immunity.” (5) received a Nobel Prize in Medicine for his work on immunity and interaction with microbes. During this research, he theorized that gut microbes found in fermented foods including yogurt might help extend life. He also correctly thought that it was possible to replace “bad” bacteria in the gut with “good” bacteria to improve overall health.
After Metchnikoff, the fire was lit and more researchers in the 20th-century found that particular strains gut microbes could impact overall health. Dr. Henry Tissier, (6) a pediatrician, found that Bifidobacterium strains were more prominent in healthy children than in children who presented with diarrhea. Other research discovered that the bacterium Lactobacillus grew well in the gut and was able to reduce constipation. Rosalie Stillwell and Daniel Lilly, from St. John’s University, researched the impact of various medical treatments that destroy gut microbes like antibiotics or radiation. They were the first to coin the term “ probiotics” and define it as a substance produced by one microorganism stimulating the growth and health of another microorganism ( like a human).
Research studies demonstrate that the probiotic concept is sound
While it is true that some products that contain probiotics have yet to prove their worth in large rigorous studies - much of this is because they are using strains that are easy to grow and manufacture but not necessarily well-adapted to the human body. However, the concept is solid. Bacteria can positively impact the immune system and protect us from diseases. The key is finding the right strains to do the job.
ATH has done just that with their probiotic product, Gut Health. It is different than many other products. This 7 strain, spore forming probiotic packs a powerful punch that delivers 5.75 billion organisms to support a healthy gut microbiome, boost digestion and supercharge the immune system. It contains both Baciullus subtilis Soil Based Organisms as well as traditional widely studied Lactobacillus & Bifidobacteria Probiotics. These strains are well adapted to the human digestive system and have been proven effective in research studies.
Modern research backs benefits of probiotics
With the passing years and more sophisticated studies, we now know more than ever about the strong connection between gut flora good health and prevention of disease. It is also being uncovered that the right strains of probiotics applied in certain circumstances can drastically improve health. (7)
Here is just a quick summary of some of the researched benefits of probiotics.
When we take an antibiotic it upsets the balance of good and bad bacteria in the gut.(8) Research indicates the positive impact that probiotics have on antibiotic-induced diarrhea: (9, 10, 11)
There is also scientific evidence supporting the use of probiotics for other types of diarrhea. When a collection of 35 studies was reviewed, it was found that probiotics had a positive influence on the duration of infectious diarrhea - reducing it by an average of 25 hours. (12)
Traveling out of country presents a unique group of health challenges. Many people experience what is known as travellers diarrhea. Research indicates that probiotics can reduce the risk of this uncomfortable condition by 8%.
A reduction in the risk of diarrhea from other causes ( 57% in kids and 26% in adults) has also been seen with probiotic use. (13)
It should be noted that particular strains of probiotics are most effective in remedying and preventing diarrhea including Lactobacillus rhamnous, Lactobacillus casei and the yeast Saccharomyces boulardii.
Mental Health Conditions
An increasing number of studies show a connection between mental health, mood and gut health. (14)
Research done on animals and humans show that probiotics can even improve some mental health disorders. A review of 15 human studies indicated that supplementation with Bifidobacterium and Lactobacllusstrans for 1-2 months improves depression, autism, anxiety, obsessive-compulsive disorder, and memory. (15)
Forty patients suffering from depression were given probiotic supplements for 8 weeks. After the 8 weeks, these patients had a noted decrease in depression levels as well as reduced levels of C-reactive protein - a marker of inflammation and reduced levels on insulin. (16)
Both elevated blood pressure and high cholesterol contribute to poor heart health. Probiotics have been found to help regulate both blood pressure and cholesterol thus contributing overall heart health.
Lactic acid producing probiotics go to work on bile in the gut keeping it from being reabsorbed in the bloodstream as cholesterol. (17,18)
A five study review revealed that eating a probiotic-infused yogurt for 2-8 weeks reduced total cholesterol by 4% and bad cholesterol by 5%. (19)
There is also evidence pointing to the fact that taking a probiotic supplement may have a positive influence on elevated blood pressure.(20)
There are over one million people in America who suffer from inflammatory bowel disorders including ulcerative colitis and irritable bowel syndrome. (21) The good news is that probiotics, specifically Bifidobacterium and Lactobacillus strains, seem to have a positive impact on this mild forms of this condition. (22) In addition, probiotics could also help reduce symptoms of irritable bowel syndrome. (23) They have also been found to reduce the risk of the fetal condition enterocolitis by 50%. (24)
There is also scientific evidence in favor of using probiotics to enhance the immune system. It appears that they can supercharge the immune system by reducing the growth of harmful gut bacteria (25).
Some strains of probiotics have demonstrated the ability to encourage production of natural antibodies and boost immune cells such as IGA-producing cell, T Lymphocytes as well as cells that kill cancer.(26)
A study of 570 children revealed that the frequency and severity of respiratory infections was reduced by 17% in children who took Lactobacillus GG (27)
The risk of women developing a urinary tract infection was reduced by 50% in another study. (28)
There is some evidence to support the use of certain probiotics to help with weight loss. (29) Some strains keep dietary fat from being absorbed in the intestine. This results in the fat being escorted out of the body via feces as opposed to being stored in the body.
A big problem with obesity is the fact that many people never feel satisfied and just keep eating. Probiotics help with the feeling of satiety and also help turn up the fat burn by elevating certain hormones such as GLP-1. (30)
Another encouraging finding is the ability of probiotics to directly impact weight loss. Women who supplemented with Lactobacillus rhamnosus for 3 months lost 50% more weight than women who did not use probiotics (31)
Yet another study of 210 people found that those that took a low dose of Lactobacillus gasseri for 12 weeks had an 8.5% reduction in belly fat. (32)
A recent study of 4,5557 newborns sheds more light on the benefits of probiotics
Since 2008 a team of researchers at the University of Nebraska Medical Center has been conducting a large-scale clinical trial in a rural area of India. (33)
They have been giving a probiotic to thousands of randomly selected newborn babies. The probiotic product contains a strain of Lactobacillus plantarum which was selected for its ability to adhere to cells in the gut. Sugar was added to the product to nourish the bacteria when it enters the baby’s stomach. This symbiotic relationship is brilliant and highly effective. A probiotic complete with a food source.
According to the research results, babies who took this probiotic had a much less risk of developing the fatal condition known as sepsis. Sepsis kills over 600,000 newborn babies each year and a number of cases of this devastating illness begin in the gut. Probiotics may be useful in preventing harmful microbes from keeping them from crossing into the bloodstream. Based on results it appears as though the administration of the specific probiotic could result in a 25%-50% reduced risk of sepsis. Although more research is definitely needed, this is a very good example of how a specific strain of probiotic can help with a specific problem.
Reputable Journal Published Papers Questioning the Viability of Probiotics
News outlets from around the world were chattering recently with the release of two back to back papers regarding the effectiveness of probiotics. (34,35)
These statements have set the “wires on fire” so to speak and there is much buzz in the news about probiotics and gut health including headlines like the following:
Listen to what senior author Eran Elinav had to say about the study,
“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,"
"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."
Was any new information uncovered?
For the most part, these studies, published in the notorious journal Cell, have not revealed much, if any, new information regarding probiotics. Let’s take a closer look.
Paper# 1: Personalized Gut Mucosal Colonization Resistance to Empiric Probiotics Is Associated with Unique Host and Microbiome Features
Finding A: For this study, the researchers took samples from the feces, gut lumen, and the gut mucosa of mice and humans. What they discovered was that each sample contained a specific type of microbe. In addition, they found that the samples found in feces were not at all a good indicator of the type of bacteria found in the gut.
Takeaway: This finding is not revolutionary as it has been known for some time that bacteria found in the mucus layer are not at all the same as those found in the lumen or stool (36). This finding just confirms the fact that stools samples do not always present an accurate picture of what is happening in the gut.
Finding B: Researchers supplemented mice for four weeks with a probiotic comprised of 11 different strains in an effort to see if it would result in colonization. At the conclusion of the study, it was found that there was no colonization, however, the probiotics did influence the health of the lower gut.
Takeaway: Again, this is not head-turning news. There have been plenty of theories supporting the fact that probiotics don’t colonize in the gut but do impact the gut community and influence the immune system as they pass through the gut. (37)
Findings C and D: Researchers tested whether or not probiotics given to germ-free mice who had no exposure to microbes would colonize. These mice were given the same 11-strain probiotic as noted above for 14 days.
At the end of the test period, it was noted that there was indeed colonization. Researchers claimed that the colonization happened because there were no existing microbes to inhibit this from happening.
The team also gave 15 healthy volunteers the same 11-strain probiotic or a placebo twice a day for four weeks.
Unlike the results found in the mice, nine of the eleven strains were found in the ascending and descending colon. As far as colonization, six participants had signs of colonization while nine did not.
However, even where it was clear that colonization had happened, researchers found no clear alterations in the microbiome of any of the 15 participants.
The study authors noted that these findings did not mean that there were no effects from the probiotics. When they considered all participants they found that consuming probiotics did have an influence on gene expression and the immune system.
Takeaway: These findings again support that probiotics merely passing through and not colonizing do have a positive impact on the immune system (38) and that in some people probiotics do colonize in the gut.
Paper# 2: Post-Antibiotic Gut Mucosal Microbiome Reconstitution Is Impaired by Probiotics and Improved by Autologous FMT
Researchers set out to discover just how effective probiotics are after broad-spectrum antibiotic use. It is a known fact that it takes a very long time for healthy bacteria to be restored after using antibiotics. Sometimes this recovery is not ever complete. (39) It is also known that antibiotic use during the early years of life is associated with an increased risk of conditions such as obesity, IBD, skin conditions, asthma, allergies, and autoimmunity. (40,41)
Studies show that providing good bacteria, in the form of probiotics, can help keep the imbalance in the gut, caused by antibiotics, from causing antibiotic-induced diarrhea in some cases. (42)
One thing new that researchers did dig into was the study of the long-term restoration of healthy bacteria in the gut after antibiotic use.
To do so, researchers gave mice and 21 healthy human participants a single course of broad-spectrum antibiotics. The participants were split into 3 groups.
Group1: Was allowed to naturally recover over time after antibiotic use.
Group 2: Was given the same 11-strain probiotic used above along with the antibiotic and for some time after the antibiotic ended.
Group 3: Was given a fecal transplant using their own fecal samples taken before antibiotic use.
Finding A: The end result of this study revealed that probiotics taken during and after a course of antibiotics compromised the return of a healthy gut microbiome and subjects did not return to baseline after the 28 day period. Once supplementation ended the imbalance in gut bacteria was seen for up to five months. This means that it took a very long time for participants gut ecosystem to return to where it was prior to the antibiotics and probiotics.
Some limitations noted by researchers included:
- A single combination of broad-spectrum antibiotics and a single oral probiotic supplement were tested.
- No clinical symptoms were measured during or after antibiotic use.
- The study was conducted on healthy subjects not those who were sick or had a compromised immune system.
Finding B: Unlike oral supplementation, a personal poop transplant resulted in a rapid and near complete recolonization of bacteria in both mice and humans. The fecal transplant allowed for the recolonization of necessary species for a healthy gut lining including Alistipes shahii, Roseburia intestinalis and Coprococcus spp.
Takeaway: Taking probiotics for diarrhea caused by antibiotic use may not be such a good idea. The better option appears to be a personal fecal transplant that results in almost complete recolonization of gut bacteria.
Making Sense of It All
What does this recent, highly publicized research tell us about probiotics? How does it commingle with the hundreds of randomized, placebo-controlled clinical trials that show the effectiveness of probiotics on a variety of conditions such as IBS, skin issues, depression, anxiety and more? (43, 44, 45)
Here are some truths to hold fast to as you navigate the big scary world of probiotics.
Truth 1: A healthy gut provides one of the greatest defenses ever against sickness and disease. The American lifestyle is not conducive to a healthy gut from consumption of denatured food to stress, lack of sleep and other lifestyle factors. When one puts a conscious effort into repairing the gut and maintaining a healthy microbiome, wellness becomes achievable.
Truth 2: Probiotics don’t have to colonize in the gut to be effective. As beneficial strains pass through the gut, they can impact gene expression as well as the immune system.
Truth 3: Not all probiotics are created equal. The unregulated nature of their use makes it difficult to assess quality. In fact, some studies have even reported human deaths related to probiotic use in clinical trials. (46, 47)
As a consumer, it is imperative to keep in mind that there is likely a great gap between probiotic strains validated in clinical trials and what you will find on your supermarket shelf. This is where personal research and education becomes critical in order to find the right product for you without wasting money or possibly impairing your wellbeing.
Truth 4: Although studies, as noted above, indicate a reduced risk of antibiotic-induced diarrhea, the reduction is small. The recent study by Israeli researchers suggests that a slight reduction in risk of diarrhea must be carefully weighed against the long-term delay of a balanced gut microbiome. Clearly, more research is needed to determine whether different strains of probiotics can offer protection from diarrhea without delaying the return of a healthy gut ecosystem.
Truth 5: A personal fecal transplant is one of the best ways to rapidly recolonize the gut after taking antibiotics. In light of this truth, we might all consider banking some of our poop from when we are younger to use for health in later life. There have actually been studies done on animals that have demonstrated that using fecal samples from young animals can help with inflammation and increase lifespan. The great news is that frozen stool can be stored for a long time without compromising the healthy bacteria. (48,49,50)
Note: If you can’t do a personal fecal transplant it is most likely best to allow your gut to recover on its own and support the restoration of a healthy gut ecosystem by eating plenty of nutrient-dense food.
Truth 6: Probiotics are not a replacement for a healthy, nutrient-rich diet loaded with plenty of live foods. If long-term health is important to you, it is imperative that you consume a healthy diet and stay clear from processed and denatured foods. Choose whole, unprocessed food, fermented, grass-fed, wild, local, seasonal and organic whenever possible. Exercise regularly, get plenty of sleep and learn as many distressing techniques as possible such as deep breathing and yoga. Doing these things help keep the balance of gut microbes in check. This, in turn, promotes good mental and physical health and provides measurable protection from inflammatory-induced illness and disease.
The Future of Probiotics
Research always begs for more research. As more truths regarding the benefits of certain probiotics for the treatment and prevention of sickness and disease are uncovered it will be important to stay on top of these discoveries. Don’t draw conclusions until you have read the facts and become knowledgeable. An educated consumer is the best consumer and you are in the driver's seat.
There is little question that the probiotics industry will continue to flourish in America and do so in a relatively unregulated fashion. This, as mentioned earlier, demands that we do our own research and come to our own conclusions as to if and how probiotics can be useful to us. It also requires us to choose only the highest quality supplements such as Gut Health.
Future studies and product creation should focus on strains that respond well in the human body and have proven to be effective in certain instances. This would help separate the valuable products from those that make wellness claims without solid scientific backing.
The truth is, the human body is an incredible machine with the ability to self-regulate and even self-heal. Our job is to give it the fodder it needs to maximize these efforts…. You should always start with a healthy lifestyle and build from there!
- Hill, C, et al. “Expert Consensus Document. The International Scientific Association for Probiotics and Prebiotics Consensus Statement on the Scope and Appropriate Use of the Term Probiotic.” Nature Reviews. Gastroenterology & Hepatology., U.S. National Library of Medicine, 11 Aug. 2014, www.ncbi.nlm.nih.gov/pubmed/24912386..
- Clemente, Jose C., et al. “The Impact of the Gut Microbiota on Human Health: An Integrative View.” Cell, Cell Press, 15 Mar. 2012, www.sciencedirect.com/science/article/pii/S0092867412001043.
- Research, Grand View. “Probiotics Market Worth To Reach $52.34 Billion, Growth At CAGR Of 7.6% Till 2020: New Report By Grand View Research, Inc.” GlobeNewswire News Room, "GlobeNewswire", 19 Nov. 2014, globenewswire.com/news-release/2014/11/19/684527/10108988/en/Probiotics-Market-Worth-To-Reach-52-34-Billion-Growth-At-CAGR-Of-7-6-Till-2020-New-Report-By-Grand-View-Research-Inc.html.
- Draper, K, et al. “Probiotic Guidelines and Physician Practice: a Cross-Sectional Survey and Overview of the Literature.” Beneficial Microbes., U.S. National Library of Medicine, 24 Aug. 2017, www.ncbi.nlm.nih.gov/pubmed/28618862.
- Gordon, S. “Elie Metchnikoff: Father of Natural Immunity.” European Journal of Immunology., U.S. National Library of Medicine, Dec. 2008, www.ncbi.nlm.nih.gov/pubmed/19039772.
- Siezen, Roland J., and Greer Wilson. “Probiotics Genomics.” Microbial Biotechnology, Blackwell Publishing Ltd, 3 Jan. 2010, www.ncbi.nlm.nih.gov/pmc/articles/PMC3815941.
- Guarner, F, and J R Malagelada. “Gut Flora in Health and Disease.” Lancet (London, England)., U.S. National Library of Medicine, 8 Feb. 2003, www.ncbi.nlm.nih.gov/pubmed/12583961.
- Dethlefsen, L, et al. “The Pervasive Effects of an Antibiotic on the Human Gut Microbiota, as Revealed by Deep 16S RRNA Sequencing.” PLoS Biology., U.S. National Library of Medicine, 18 Nov. 2008, www.ncbi.nlm.nih.gov/pubmed/19018661.
- Goldenberg, J Z, et al. “Probiotics for the Prevention of Pediatric Antibiotic-Associated Diarrhea.” The Cochrane Database of Systematic Reviews., U.S. National Library of Medicine, 22 Dec. 2015, www.ncbi.nlm.nih.gov/pubmed/26695080.
- Hempel, S, et al. “Probiotics for the Prevention and Treatment of Antibiotic-Associated Diarrhea: a Systematic Review and Meta-Analysis.” JAMA., U.S. National Library of Medicine, 9 May 2012, www.ncbi.nlm.nih.gov/pubmed/22570464.
- Johnston, B C, et al. “Probiotics for the Prevention of Pediatric Antibiotic-Associated Diarrhea.” The Cochrane Database of Systematic Reviews., U.S. National Library of Medicine, 9 Nov. 2011, www.ncbi.nlm.nih.gov/pubmed/22071814.
- Allen, S J, et al. “Probiotics for Treating Acute Infectious Diarrhoea.” The Cochrane Database of Systematic Reviews., U.S. National Library of Medicine, 10 Nov. 2010, www.ncbi.nlm.nih.gov/pubmed/21069673.
- Sazawal, S, et al. “Efficacy of Probiotics in Prevention of Acute Diarrhoea: a Meta-Analysis of Masked, Randomised, Placebo-Controlled Trials.” The Lancet. Infectious Diseases., U.S. National Library of Medicine, June 2006, www.ncbi.nlm.nih.gov/pubmed/16728323.
- Steenbergen, L, et al. “A Randomized Controlled Trial to Test the Effect of Multispecies Probiotics on Cognitive Reactivity to Sad Mood.” Brain, Behavior, and Immunity., U.S. National Library of Medicine, Aug. 2015, www.ncbi.nlm.nih.gov/pubmed/25862297.
- Wang, H, et al. “Effect of Probiotics on Central Nervous System Functions in Animals and Humans: A Systematic Review.” Journal of Neurogastroenterology and Motility., U.S. National Library of Medicine, 30 Oct. 2016, www.ncbi.nlm.nih.gov/pubmed/27413138.
- Akkasheh, G, et al. “Clinical and Metabolic Response to Probiotic Administration in Patients with Major Depressive Disorder: A Randomized, Double-Blind, Placebo-Controlled Trial.” Nutrition (Burbank, Los Angeles County, Calif.)., U.S. National Library of Medicine, Mar. 2016, www.ncbi.nlm.nih.gov/pubmed/26706022.
- Begley, M, et al. “Bile Salt Hydrolase Activity in Probiotics.” Applied and Environmental Microbiology., U.S. National Library of Medicine, Mar. 2006, www.ncbi.nlm.nih.gov/pubmed/16517616.
- Kumar, M, et al. “Cholesterol-Lowering Probiotics as Potential Biotherapeutics for Metabolic Diseases.” Experimental Diabetes Research., U.S. National Library of Medicine, 3 May 2012, www.ncbi.nlm.nih.gov/pubmed/22611376.
- Fahey, J L. “Present Status of Immunoglobulin Research.” Archives of Internal Medicine., U.S. National Library of Medicine, Jan. 1975, www.ncbi.nlm.nih.gov/pubmed/1111468.
- Khalesi, S, et al. “Effect of Probiotics on Blood Pressure: a Systematic Review and Meta-Analysis of Randomized, Controlled Trials.” Hypertension (Dallas, Tex. : 1979)., U.S. National Library of Medicine, 6 Oct. 2014, www.ncbi.nlm.nih.gov/pubmed/25047574.
- Kappelman, Michael D., et al. “Recent Trends in the Prevalence of Crohn’s Disease and Ulcerative Colitis in a Commercially Insured US Population.” Digestive Diseases and Sciences, Springer US, 20 Aug. 2012, www.ncbi.nlm.nih.gov/pmc/articles/PMC3576554/.
- Saez-Lara, M J, et al. “The Role of Probiotic Lactic Acid Bacteria and Bifidobacteria in the Prevention and Treatment of Inflammatory Bowel Disease and Other Related Diseases: a Systematic Review of Randomized Human Clinical Trials.” BioMed Research International., U.S. National Library of Medicine, 22 Feb. 2015, www.ncbi.nlm.nih.gov/pubmed/25793197.
- Moayyedi, P, et al. “The Efficacy of Probiotics in the Treatment of Irritable Bowel Syndrome: a Systematic Review.” Gut., U.S. National Library of Medicine, 17 Dec. 2008, www.ncbi.nlm.nih.gov/pubmed/19091823.
- AlFaleh, K, and J Anabrees. “Probiotics for Prevention of Necrotizing Enterocolitis in Preterm Infants.” The Cochrane Database of Systematic Reviews., U.S. National Library of Medicine, 10 Apr. 2014, www.ncbi.nlm.nih.gov/pubmed/24723255.
- Resta-Lenert, S, and K E Barrett. “Live Probiotics Protect Intestinal Epithelial Cells from the Effects of Infection with Enteroinvasive Escherichia Coli (EIEC).” Gut., U.S. National Library of Medicine, July 2003, www.ncbi.nlm.nih.gov/pubmed/12801956.
- Reid, G, et al. “Potential Uses of Probiotics in Clinical Practice.” Clinical Microbiology Reviews., U.S. National Library of Medicine, 16 Oct. 2003, www.ncbi.nlm.nih.gov/pubmed/14557292.
- Hatakka, K, et al. “Effect of Long Term Consumption of Probiotic Milk on Infections in Children Attending Day Care Centres: Double Blind, Randomised Trial.” BMJ (Clinical Research Ed.)., U.S. National Library of Medicine, 2 June 2001, www.ncbi.nlm.nih.gov/pubmed/11387176.
- Stapleton, A E, et al. “Randomized, Placebo-Controlled Phase 2 Trial of a Lactobacillus Crispatus Probiotic given Intravaginally for Prevention of Recurrent Urinary Tract Infection.” Clinical Infectious Diseases : an Official Publication of the Infectious Diseases Society of America., U.S. National Library of Medicine, 14 Apr. 2011, www.ncbi.nlm.nih.gov/pubmed/21498386.
- Angelakis, E, et al. “Related Actions of Probiotics and Antibiotics on Gut Microbiota and Weight Modification.” The Lancet. Infectious Diseases., U.S. National Library of Medicine, 13 Oct. 2013, www.ncbi.nlm.nih.gov/pubmed/24070562.
- Yadav, H, et al. “Beneficial Metabolic Effects of a Probiotic via Butyrate-Induced GLP-1 Hormone Secretion.” The Journal of Biological Chemistry., U.S. National Library of Medicine, 30 Aug. 2013, www.ncbi.nlm.nih.gov/pubmed/23836895.
- Sanchez, M, et al. “Effect of Lactobacillus Rhamnosus CGMCC1.3724 Supplementation on Weight Loss and Maintenance in Obese Men and Women.” The British Journal of Nutrition., U.S. National Library of Medicine, 3 Dec. 2013, www.ncbi.nlm.nih.gov/pubmed/24299712.
- Kadooka, Y, et al. “Effect of Lactobacillus Gasseri SBT2055 in Fermented Milk on Abdominal Adiposity in Adults in a Randomised Controlled Trial.” The British Journal of Nutrition., U.S. National Library of Medicine, 14 Nov. 2013, www.ncbi.nlm.nih.gov/pubmed/23614897.
- Panigrahi, P, et al. “A Randomized Synbiotic Trial to Prevent Sepsis among Infants in Rural India.” Nature., U.S. National Library of Medicine, 24 Aug. 2017, www.ncbi.nlm.nih.gov/pubmed/28813414.
- Zmora, N, et al. “Personalized Gut Mucosal Colonization Resistance to Empiric Probiotics Is Associated with Unique Host and Microbiome Features.” Cell., U.S. National Library of Medicine, 6 Sept. 2018, www.ncbi.nlm.nih.gov/pubmed/30193112.
- Suez, J, et al. “Post-Antibiotic Gut Mucosal Microbiome Reconstitution Is Impaired by Probiotics and Improved by Autologous FMT.” Cell., U.S. National Library of Medicine, 6 Sept. 2018, www.ncbi.nlm.nih.gov/pubmed/30193113.
- Donaldson, Gregory P., et al. “Gut Biogeography of the Bacterial Microbiota.” Nature Reviews. Microbiology, U.S. National Library of Medicine, 14 Jan. 2016, www.ncbi.nlm.nih.gov/pmc/articles/PMC4837114/.
- Corthésy, B, et al. “Cross-Talk between Probiotic Bacteria and the Host Immune System.” The Journal of Nutrition., U.S. National Library of Medicine, Mar. 2007, www.ncbi.nlm.nih.gov/pubmed/17311975.
- Ohland, C L, and W K Macnaughton. “Probiotic Bacteria and Intestinal Epithelial Barrier Function.” American Journal of Physiology. Gastrointestinal and Liver Physiology., U.S. National Library of Medicine, 18 Mar. 2010, www.ncbi.nlm.nih.gov/pubmed/20299599.
- Dethlefsen, L, and D A Relman. “Incomplete Recovery and Individualized Responses of the Human Distal Gut Microbiota to Repeated Antibiotic Perturbation.” Proceedings of the National Academy of Sciences of the United States of America., U.S. National Library of Medicine, 15 Mar. 2011, www.ncbi.nlm.nih.gov/pubmed/20847294.
- Zanvit, P, et al. “Antibiotics in Neonatal Life Increase Murine Susceptibility to Experimental Psoriasis.” Nature Communications., U.S. National Library of Medicine, 29 Sept. 2015, www.ncbi.nlm.nih.gov/pubmed/26416167.
- Marra, F, et al. “Does Antibiotic Exposure during Infancy Lead to Development of Asthma?: a Systematic Review and Metaanalysis.” Chest., U.S. National Library of Medicine, Mar. 2006, www.ncbi.nlm.nih.gov/pubmed/16537858.
- Hempel, S, et al. “Probiotics for the Prevention and Treatment of Antibiotic-Associated Diarrhea: a Systematic Review and Meta-Analysis.” JAMA., U.S. National Library of Medicine, 9 May 2012, www.ncbi.nlm.nih.gov/pubmed/22570464.
- Moayyedi, P, et al. “The Efficacy of Probiotics in the Treatment of Irritable Bowel Syndrome: a Systematic Review.” Gut., U.S. National Library of Medicine, 17 Mar. 2008, www.ncbi.nlm.nih.gov/pubmed/19091823.
- Messaoudi, M, et al. “Beneficial Psychological Effects of a Probiotic Formulation (Lactobacillus Helveticus R0052 and Bifidobacterium Longum R0175) in Healthy Human Volunteers.” Gut Microbes., U.S. National Library of Medicine, 1 July 2011, www.ncbi.nlm.nih.gov/pubmed/21983070.
- Weston, S, et al. “Effects of Probiotics on Atopic Dermatitis: a Randomised Controlled Trial.” Archives of Disease in Childhood., U.S. National Library of Medicine, 29 Apr. 2005, www.ncbi.nlm.nih.gov/pubmed/15863468.
- Besselink, M G, et al. “Probiotic Prophylaxis in Predicted Severe Acute Pancreatitis: a Randomised, Double-Blind, Placebo-Controlled Trial.” Lancet (London, England)., U.S. National Library of Medicine, 23 Feb. 2008, www.ncbi.nlm.nih.gov/pubmed/18279948..
- Vogel, Gretchen. “Deaths Prompt a Review of Experimental Probiotic Therapy.” Science, American Association for the Advancement of Science, 1 Feb. 2008, science.sciencemag.org/content/319/5863/557.1.
- Kodroff, Lauren Hllary, and Elizabeth B Norton. “Impact of Microbiome Manipulation on Age-Related Inflammation and Immune System Dysfunction.” The Journal of Immunology, 1 May 2016, www.jimmunol.org/content/196/1_Supplement/214.22.
- Smith, Patrick, et al. “Regulation of Life Span by the Gut Microbiota in The Short-Lived African Turquoise Killifish.” BioRxiv, Cold Spring Harbor Laboratory, 1 Jan. 2017, www.biorxiv.org/content/early/2017/03/27/120980.
- “Latitude in Sample Handling and Storage for Infant Faecal ...” Port of Springer Nature, Microbiome, 8 Mar. 2016, link.springer.com/content/pdf/10.1186/s40168-016-0186-x.pdf.