Learning Objectives To learn what are probiotics Their effects on our health Sources Side effects
Introduction The World Health Organization definesprobiotics as “live microorganisms, whichwhen administered in adequate amountsconfer a health benefit on the host.” The most common types of thesebeneficial bacteria areLactobacilli and Bifidobacteria.
Our body contains millionsof bacteria living naturally invarious parts. These arecalled “Commensals.” However, in the past fewdecades, many of thesecommensals were seen toproduce actual beneficialeffects on the body. They were then renamed“probiotic” bacteria.
There are several reasons that people areinterested in probiotics for health purposes. Friendly bacteria are vital to proper developmentof the immune system, to protection againstmicroorganisms that could cause disease, and toaid the digestion and absorption of food andnutrients. Each persons mix of bacteria varies. Interactions between a person and themicroorganisms in his body, and among themicroorganisms themselves, can be crucial to thepersons health and well-being.
Recent findings It is known that an imbalanced intestinalmicrobiota predisposes to Cl. difficile infections,IBD and IBS. The complex role of intestinal microbiota tomaintain health, however, is a newer concept thatis being increasingly studied. The microbiome plays an important role in cellularimmunity and energy metabolism and has beenimplicated in the pathogenesis of non-GIautoimmune diseases, chronic fatigue syndrome,obesity and even some neuropsychiatric disorders. Curr Opin Gastroenterol. 2013;29(1):79-84.
The original observation of the positive role playedby certain bacteria was first introduced by Russianscientist and Nobel laureate Élie Metchnikoff, whoin the beginning of the 20th century suggestedthat it would be possible to modify the gutflora and to replace harmful microbes with usefulmicrobes. The term "probiotics" was first introduced in 1953by Werner Kollath. In 1989, Roy Fuller suggested a definition ofprobiotics that has been widely used: "A livemicrobial feed supplement which beneficiallyaffects the host animal by improving its intestinalmicrobial balance".
The bacteria and yeasts The probiotics come from two groups, Bacteria: Lactobacillus and Bifidobacterium. Within each group, there are different species (forexample, Lactobacillus acidophilus andBifidobacterium bifidus), and within each species,different strains (or varieties). Yeasts and fungi: Saccharomyces boulardii andRhizopus.
Diarrhea Some probiotics have been shown to treat variousforms of gastroenteritis. Fermented milk products (such as yogurt) reducethe duration of symptoms, the duration of illnessand the frequency of stools. Antibiotic-associated diarrhea (AAD) results from an imbalance in the colonicmicrobiota caused by antibiotic therapy.Microbiota alteration changes carbohydratemetabolism with decrease short-chain fattyacid absorption and an osmotic diarrhea as aresult.
Another consequence of antibiotic therapyleading to diarrhea is overgrowth ofpotentially pathogenic organisms suchas Clostridium difficile. Probiotic treatment might reduce the incidenceand severity of AAD. For example, treatment with probiotic-formulationsincluding Lactobacillus rhamnosus may reduce therisk of antibiotic-associated diarrhea, improve stoolconsistency during antibiotic therapy, andenhance the immune response after vaccination.
Lactose intolerance As lactic acid bacteriaactively convert lactoseinto lactic acid, ingestion ofcertain active strains may helplactose intolerant individualstolerate more lactose thanthey would otherwise havetolerated. Having yoghurt is a good wayfor a lactose intolerant personto get calcium.
Colon cancer In laboratory investigations, somestrains of LAB have demonstratedanti-mutagenic effects thoughtto be due to their ability to bindwith heterocyclic amines, whichare carcinogenic substancesformed in cooked meat. Animal studies havedemonstrated that some LABhave evidence for actingagainst colon cancer.
Cholesterol Some studies have demonstrated the efficacy ofsome strains of LAB to be able to lowerserum cholesterol levels, presumably by breakingdown bile in the gut, thus inhibiting its reabsorption(bile aid is synthesized from cholesterol). Obesity Recent research has shown that probioticbacteria can reduce the inflammatory effects ofabdominal fat and also reduce appetite byenhancing incretin effects.
Blood pressure Some studies have indicated that consumptionof milk fermented with various strains of LAB mayresult in modest reductions in blood pressure, aneffect possibly related to the ACE inhibitor-like peptides produced during fermentation.
Immune function and infections Some strains of LAB affect pathogens by meansof competitive inhibition (i.e., by competing forgrowth). There is also evidence to suggest that they mayimprove immune function by increasing thenumber of IgA-producing plasma cells (B cells) They also help by increasing or improvingphagocytosis as well as increasing the proportionof T lymphocytes
Clinical trials have demonstrated that probioticsmay decrease the incidence of respiratory tractinfections and dental caries in children. LAB products might aid in the treatmentof rotavirus infections in children and travelersdiarrhea in adults. Antibiotics seem to reduce immune systemactivity as a result of killing off the normal gutbacteria.
Helicobacter pylori Some strains of LAB may affect Helicobacterpylori infections (which may cause peptic ulcersand GERD) in adults when used in combinationwith standard medical treatments, but there isno standard in medical practice or regulatoryapproval for such treatment.
Inflammation Some strains of LAB may modulateinflammatory and hypersensitivity responses. Clinical studies suggest that they can preventrecurrences of inflammatory bowel disease inadults. How probiotics may influence the immune systemremains unclear, but a potential mechanismunder research concerns the response of T-lymphocytes to pro-inflammatory stimuli and inpart due to the regulation of cytokine function.
Absorption of Iron and Calcium Probiotics + prebiotics(insoluble starches) canincrease iron and calcuim absorption from theintestines. There is increased solubility of minerals because of 1. increased bacterial production of short-chainfatty acids; 2. an enlargement of the absorption surface bypromoting proliferation of enterocytes; 3. increased expression of calcium-bindingproteins; 4. degradation of phytic acid.
Uses for health purposes Antibiotic associated diarrhoea (AAD): antibioticskill friendly bacteria in the gut along with unfriendlybacteria. Some people use probiotics to try to offset sideeffects from antibiotics like gas, cramping,or diarrhea. Lactose intolerance: this is a condition in which thegut lacks the enzyme needed to digest the majorsugar in milk, lactose, and this causesgastrointestinal symptoms. Probiotics can help byfermenting the lactose and breaking it down tolactic acid and water.
Infectious diarrhea. To treat diarrhea this is the strongest area ofevidence with diarrhoeas due to Clostridiumdifficile and Rotavirus. Irritable bowel syndrome. Probiotics have beenassociated with an improvement in IBS symptomscompared with placebo. Studies suggestdecreases in some patients’ abdominal pain,bloating, and gas. Bifidobacterium and Lactobacillus strains haveboth been studied for their potential use inpreventing and managing IBS symptoms.
Patients with constipation-predominant IBS havebeen shown to increase population of sulphate-reducing bacteria compared with healthycontrols. Probiotics can restore the intestinal microbiota inpatients with IBS and result in improvement ofpostinfectious IBS. Fecal Microbiome Transfer (FMT), however, mayprove more beneficial, as donated feces, in asense, are the ultimate human probiotic. Olga C. Aroniadis, Lawrence J. Brandt, Curr OpinGastroenterol. 2013;29(1):79-84.
Inflammatory bowel disease (e.g., ulcerativecolitis and Crohns disease) Probiotics have shown toreduce the symptoms of inflammatory boweldisease, along with mesalazine. Patients with IBD have an abundance ofEnterobacteriaceae and paucityof Faecalibacterium. IBD patients also have 30–50% reduction in thebiodiversity of their intestinal microbiota. FMT for refractory ulcerative colitis has beendescribed in four publications, comprising ninepatients, all of whom had severe, activelongstanding ulcerative colitis (mean, 8.6 years)refractory to treatment with corticosteroids, 5-aminosalicylates and azathiaprine.
Infection with Helicobacter pylori (H. pylori), abacterium that causes most ulcers and manytypes of chronic stomach inflammation. The routine treatment for H, pylori infection isantibiotics but some patients may have difficultygetting rid of the infection with standardantibiotic therapy. There is evidence to suggest that addingprobiotics to the treatment regime may help toincrease the chances of H. pylori eradication.
Treatment of Non-gastrointestinalDiseases Studies in germ-free animals suggest that intestinalmicrobiota may contribute to pathogenesis ofnon-GI diseases. Germ-free animals exhibit dysregulation of theirhypothalamic–pituitary–adrenal axis leading to anexaggerated stress response, impaired cardiacoutput, altered brain derived hormones (e.g.,norepinephrine and tryptophan) and increasedcaloric intake to maintain body weight.
Moreover, the microbiota may play a role inpathogenesis of various neurologic disorders anddata support the concept of the brain–gut–microbiota axis. Microbiota residing on the skin and mucosalsurfaces of the nose and mouth may determinethe development of acne, common cold,periodontal disease, meningococcemia andallergic rhinitis.
Probiotics may be useful in themanagement of: Vaginal infections Stomach and respiratory infections that childrenacquire in day-care To prevent and treat infections of the urinarytract or female genital tract. To reduce recurrence of bladder cancer. To prevent and manage atopic dermatitis(eczema) in children. To Prevent tooth decay and periodontal disease.
Still being studied Idiopathic Thrombocytopenic purpura Multiple sclerosis Parkinson’s disease Obesity Chronic fatigue syndrome Autism Auto-immune disorders
Prevents Radiotherapy side-effects Researchers from the Washington UniversitySchool of Medicine in St. Louis, USA, have foundthat radiation therapy patients who takeprobiotics prior to getting blasted can gainintestinal radio-protective benefits. They found that those who had received aprobiotic mix that included Lactobacillusrhamnosus before exposure were protectedagainst radioactive damage to their intestines.
From food Since early times, traditions spanning the globehave been fermenting or culturing foods fornutrition, preserving the amazing taste sensationsof these health supporting food ferments.
Strains Live probiotic cultures are available infermented dairy products and probioticfortified foods. However, tablets, capsules, powders andsachets containing the bacteria in freezedried form are also available.
Bacillus coagulans GanedenBC30 GanedenBiotechMay improve abdominal pain andbloating in IBS patients. Mayincrease immune response to aviral challenge.BifidobacteriumanimalisProbio-TecBifidobacteriumBB-12Chr. HansenHuman studies have shown thatBB-12 alone or in combinationmay have an effect on thegastrointestinal system.BifidobacteriuminfantisAlign Procter &GambleIn one preliminary study, showedpossible improvement forabdominal pain/discomfort andbowel movement difficulty.Lactobacillusacidophilus NCFM Danisco Shown in one study to reduce theside effects of antibiotic therapy.LactobacillusparacaseiLactobacillusjohnsoniiNestléMay reduce incidence of H pylori-caused gastritis and may reduceinflammation
Lactobacillusreuteri BioGaiaPreliminary evidence fordiarrhea mitigation inchildren, H. Pyloriinfection possible effecton gingivitis, fever inchildren and number of sickdays in adults.SaccharomycesboulardiiWrenLaboratoriesLimited evidence fortreatment of acute diarrhea.Tested asmixture:Lactobacillusrhamnosus& LactobacillusreuteriBion FloreIntime/JarrowFem-DophilusChr.HansenIn one study, oral ingestionresulted in vaginalcolonisation and reducedvaginitis.Tested asmixture:Lactobacillusacidophilus & BifidobacteriumbifidusFlorajen3 AmericanLifeline, IncPreliminary evidence forreduced C. Difficileassociated disease (CDAD)
Tested asmixture:Lactobacillusacidophilus&LactobacilluscaseiBio-K+CL1285Bio-K+InternationalMay affect digestivehealth.In vitro inhibition of Listeriamonocytogenes and L.innocua, Escherichiacoli,Staphylococcusaureus, Enterococcusfaecalis and Enterococcusfaecium.Reduction of symptoms oflactose intolerance andimmune stimulation.Lactobacillusplantarum &LactobacillusparacaseiBravoFriscus/ProbiFriskProbi Is under study for common coldinfections.
Yogurt Yogurt or yoghurt is a dairy product producedby bacterial fermentation of milk. The bacteria used to make yogurt are known as"yogurt cultures". Fermentation of lactose by these bacteriaproduces lactic acid, which acts on milk protein togive yogurt its texture and its characteristic tang. Worldwide, cows milk is most commonly used tomake yogurt, but milk from waterbuffalo, goats, sheep, horses, camels and yaks isalso used in various parts of the world.
Dairy yogurt is produced using a cultureof Lactobacillus bulgaricus and Streptococcussalivarius subsp. thermophilus bacteria. In addition, other lactobacilli andbifidobacteria are also sometimes added duringor after culturing yogurt.
Cheese Select cheese products also contain probiotics,including Krafts LiveActive natural cheese snacks,and Specially Selected Amish Yogurt Cheese(prepared with the probiotic live culturesLactobacillus acidophilus and bifido bacterium). Other good sources of probiotics include bluecheese and other aged cheeses. Probiotic-rich cheeses often feature words such as"live culture," "active culture" or "probiotics" on thepackaging.
Buttermilk Buttermilk refers to a number of dairy drinks. Originally,buttermilk was the liquid left behind afterchurning butter out of cream. This type of buttermilk isknown as traditional buttermilk. The tartness of buttermilk is due to acid in the milk. Theincreased acidity is primarily due to lacticacid produced by lactic acid bacteria whilefermenting lactose, the primary sugar in milk. As the bacteria produces lactic acid, the pH of themilk decreases and casein, the primary milk protein,precipitates, causing the curdling of milk. This process makes buttermilk thicker than plain milk.
Kombucha Kombucha is a tangy/sweet "mushroom tea",referred to as the "immortal health elixir" datingback to the Chinese Qin Dynasty The "mushroom" culture is not technically amushroom, but a round pancake-like, firm jellystructure, called "the mother." It is a membrane of yeasts and bacteria thatcovers the top of the liquid.
The yeast component of kombucha may containany of Saccharomyces cerevisiae, Brettanomycesbruxellensis, or Candida stellata. The acidity and mild alcoholic element ofkombucha resists contamination by most airbornemoulds or bacterial spores. As a result, kombucha is relatively easy to maintainas a culture outside of sterile conditions. The bacteria and yeasts in kombucha may alsoproduce antimicrobial defense molecules.
It contains a compound called glucaric acid,which enhances the liver’s secretions. Glucaric acid is being researched as a possiblecancer inhibitor. It helps to ensure acid/alkaline balance in thebody. This fermented drink is also rich in antioxidantsand other protein balancing amino acids, suchas L-threonine.
Sauerkraut/Khimchi Sauerkraut is the ancient art of culturing,fermenting and pickling vegetables thatdates back thousand of years. The word “sauerkraut” comes from theGerman language meaning “sour plants." It is commonly believed to have beenbrought to Europe from China, wherefermented cabbage was eaten as anancient food. Today, it is popular all across Europe, aswell as in Asian cuisine and culture. The Korean version is known as "kimchee."
Basically, it is shreddedcabbage fermented in itsown juice with salt. Other vegetables andspices can be added forextra flavour and variety. Over time, between 3-7days, the vegetablesbecome sweeter, soft,slightly pickled, tangy, andincredibly tasty.
The fermentation process allows for theproduction of lactic acid and the proliferation ofbeneficial bacteria, such as, Lactobacillus, andPediococcus. This also lowers pH, creating an acid environment,where friendly flora can reproduce. Chinese workers building the Great Wall of Chinaconsumed this food in great quantities.
Kimchi contains a high concentration of dietaryfiber, while being low in calories. One serving also provides over 50% of the dailyrecommended amount of vitaminC and carotene. Kimchi is rich in vitamin A, thiamine (B1), riboflavin(B2), calcium, and iron, and contains a numberof lactic acid bacteria, among those the typicalspecies Lactobacillus kimchii. “Health” magazine named kimchi in its list of topfive "Worlds Healthiest Foods" for being rich invitamins, aiding digestion, and even possiblyreducing cancer growth
Tempeh Tempeh: - is a rich whole bean cake; high inprotein because of its method of fermentation. Tempeh or fermented bean cake originated over2,000 years ago in Indonesia and the island ofJava, where it is still a main food today. The white mycelium of the spore, Rhizopusoligosporus, forms a solid bean cake, which canbe sliced, fried or steamed as an alternative tomeat. For those wanting to cut back on red meats orchicken, it is a great substitute with no cholesterol.
Tempeh is easy to digest becausethe beans are pre-digested by thespore culture, which also providesbeneficial micro-flora to theintestinal tract. One of the main reasons why weferment foods is to make themmore digestible. So, for those who can not usuallyhandle eating beans, this is theperfect solution. You can eat your"bean cake" and digest it too!
Kefir Kefir:- originating in the Caucasus of Russia andTurkey, kefir - is a fermented milk drink high inprobiotic cultures. It is a tart yogurt-like fermented food thatcontains friendly bacteria and yeasts that worktogether to provide natural antibiotic properties.
Kefir has tremendous healing power. Its beneficial bacteria and yeast help control thepathogenic yeast and repopulate the colon witha favorable, new life force. It is made from sheeps, cows or goats milk or, asan alternative to dairy, it can be made withcoconut milk. This "medicinal drink" coats the stomach lining andcontains tryptophan, an amino acid that workswith calcium and magnesium to relax the nerves.
The culture, or “Kefir grains", is ablend of friendly yeast andbacteria that form a mix of lipids,sugars and proteins that gel upinto a thick, yogurt-like liquidconsistency. The "tara" grains of the Tibetanpeoples are a cousin to thiscultured grain, which hasprovided them with a similarfermented drink for eons.
Miso Miso:- a traditional Japanese food, miso is a richsalty paste made from grains, beans and kojispores. Its origins date back to China in 3rd century BC.The version we know today was later adoptedby the Buddhist and Japanese cultures. Koji or Aspergillus oryzae spore is a B-12synthesizing organism that is used to culture orferment the beans and grains, muchlike kefir grains or kombucha mushroom.
Natural miso is a living food containing manybeneficial microorganisms such asTetragenococcus halophilus and lactobaccilusacidophilus which can be killed by over-cooking. For this reason, it is recommended that the misobe added to soups or other foods beingprepared just before they are removed from theheat. Using miso without any cooking may be evenbetter.
Tapai Tapai is a very popular fermented snack in Asiancountries. It can be prepared using either glutinousrice (Oryza sativa glutinosa) or cassava tuber(Manihot utilisima). Usually, saccharomyces fungi are used in thefermentation process. After fermentation, the glutinous rice or cassava issoft and juicy. Tapai is a popular dessert/snack with a sweet andacidic taste with mild alcoholic flavour.
Fermentation is performed by a variety of mouldsincluding Aspergillus oryzae, Rhizopusoryzae, or Mucor species, and yeasts includingSaccharomyces cerevisiae, andSaccharomycopsis fibuliger, and others. Tapai is made by inoculating a carbohydratesource with the required microorganisms in a starterculture. The culture can be naturally captured from thewild, by mixing rice flour with ground spices canesugar or coconut water, slices of ginger, and waterto make a dough.
The dough is pressed into round cakes, and leftto incubate on trays with banana leaves underand over them for two to three days. They are then dried and stored. It is a perishableproduct and has to be consumed immediately(within 3 to 4 days) after the optimum stage offermentation.
Soy sauce (also called soya sauce) isa condiment produced by fermenting soybeanswith Aspergillus oryzae or Aspergillussojae molds, along with water and salt. After the fermentation, which yields fermentedsoybean paste, the paste is pressed, and twosubstances are obtained: a liquid, which is thesoy sauce, and a cake of (wheat and) soyresidue.
Side effects and risks Some live microorganisms have a long history ofuse as probiotics without causing illness in people. Probiotics safety has not been thoroughly studiedscientifically, however. More information is especially needed on howsafe they are for young children, elderly people,and people with compromised immune systems.
Known side effects Probiotics side effects, if they occur, tend to bemild and digestive (such as gas or bloating). Probiotics might theoretically cause infectionsthat need to be treated with antibiotics,especially in people with underlying healthconditions. They could also cause gene transfer (insertion ofgenetic material into a cell). Probiotic products taken by mouth as a dietarysupplement are manufactured and regulated asfoods, not drugs.
The available evidence in RCTs does not indicatean increased risk; however, rare adverse eventsare difficult to assess, and despite the substantialnumber of publications, the current literature is notwell equipped to answer questions on the safetyof probiotic interventions with confidence. There are no reported ill consequences of naturalprobiotic use in literature in-spite of centuries ofuse.
Are probiotics supplements necessary? Probiotics supplements are not necessary fornormal, healthy individuals. If you are healthy, daily consumption ofprobiotics-rich foods, particularly fermenteddairy products like yoghurt and cultured milkdrinks, should adequately supply the amount ofprobiotics required to maintain a healthydigestive system and overall wellbeing. A diet high in Resistant starches and fibreprovide Prebiotics, which keep a healthypopulation of probiotics in our intestines.