Probiotics: Overview

There are more than 400 different species of bacteria in the human digestive tract.  The most important of these are Lactobacillus acidophilus and Bifidobacterium bifidum.  They are called probiotics, the opposite of antibiotics, because they aid in creating a healthy balance of microflora in the gut.

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Wrongly described as the body's sewer, the colon is actually buzzing with life activity.  Millions of friendly bacteria are hard at work in the colon.  Their job is the final stage of digestion, leaving only what is absolutely of no use to the body to be eliminated.  The friendly bacteria, weighing as much as three pounds in the normal colon, also function to keep bad bacteria in check.  It seems that most bacteria in the world and in the body are actually beneficial to our health.  Bacteria are the janitors of the world, disposing of decaying and diseased cells.

The human gastrointestinal tract – the small and large intestines – is home for these hundreds of species of bacteria.  There are several thousand billion of them in each of us, and the total weight of bacteria is between 3-4 pounds.  These bacteria play important an important part in human digestion and immune function.  "Probiotics" are live or dead bacteria administered to humans for the purpose of improving their health.  The word comes from Greek "pro bios" meaning "for life".


Generally you should use products that contain a mixture of live organisms and have an expiration date on the label.  Extreme heat or freezing can kill the live cells.  Food sources of probiotics include yogurt and milk with live cultures – but note that Pasteurization destroys live cultures.

The probiotics generally should be stored in refrigerator because they lose their potency (heat will kill bacteria) at room temperature.  Some manufacturers claim that their probiotics can survive at room temperature and therefore do not require refrigeration, but these statements should be treated with suspicion: It is recommended to purchase probiotics from a health store that keeps them in a refrigerator.

Most digestive bacteria cannot survive the strong hydrochloric acid in the stomach.  Therefore, use of probiotics in enteric coated capsules is recommended, as they will only dissolve in the lower intestine and thereby avoid the stomach's hydrochloric acid.

Problems with Lactobacillus administration include the failure of organisms to adhere to the intestinal mucosa or to survive damage from gastric acid and bile.  The acidophilus sweepstakes has led to the search for newer and better strains for medical uses.

Supplements of fructooligosaccharides (FOS) promote the growth of Bifidobacteria.  Bifidobacteria use the fiber from foods such as fruits, vegetables, legumes and grains to make short-chain fatty acids, including butyrate.  Butyrate is an important source of energy for the cells lining the colon and promote a healthy colon.  The recommended dose of FOS is 2-3gm per day.  Foods containing fructooligosaccharides include onions, asparagus, garlic and Jerusalem artichokes.

Function; Why it is Recommended

The primary use of probiotics is to restore the normal flora in the intestines that often occurs because of poor diet or the use of antibiotics.  They do this first by competing with other organisms for nutrients.  They secrete lactic acid and acetic acid that decrease the pH of the vagina and intestines, making the environment less favorable for the pathogenic bacteria to thrive.  Antibiotics can alter the bacteria in the gastrointestinal tract, decreasing the numbers of healthy bacteria and causing diarrheaProbiotics, taken during or after antibiotic therapy, can reduce or prevent this effect.

Probiotics produce certain antimicrobial compounds that kill some of the undesirable pathogens in the intestines, including yeasts, virii and bacteria.  The associated decrease in the production of potentially cancer-causing toxins by the unfavorable microorganisms may help decrease the incidence of colon cancer.  Probiotics also make certain vitamins needed by the body including folic acid, vitamin B6, niacin and vitamin K.

Low counts of Lactobacillus and Bifidobacterium, with an increase in less desirable bacteria in the intestines can cause gas, diarrhea, constipation, mucosal irritation and contribute to the development of allergies.  As the number of undesirable bacteria increases, the absorption of certain nutrients, including the B-vitamins, decreases, leading to the possibility of deficiencies.

Unfortunately, new generations of antibiotics can significantly reduce number of bacteria in few weeks or even days.  Generally, antibiotics are not able to differ good bacteria from bad and prolonged use of antibiotics can significantly decrease number of friendly bacteria.  If you suspect that the digestive flora have been disrupted by antibiotics (typical symptoms include diarrhea, abdominal discomfort and gas), have a comprehensive stool analysis performed in order to check the proper balance of bacterial flora.  If you cannot avoid taking antibiotics it is advised to take probiotics 2-3 hours after taking the antibiotics.

Other factors that deplete friendly bacteria include: medicines, infections (bacterial, viral and fungal), a highly processed, low-fiber diet, chronic diarrhea and stress.

Probiotics help us in many different ways such as:

  • Kill or inhibit harmful bacteria by secreting small quantities of antibiotic-like substances, including lactic acid, acetic acid, benzoic acid, hydrogen peroxide, acidolin, lactocidin and acidophilin.
  • Kill or inhibit yeast growth.
  • Produce vitamins, including niacin, folic acid, biotin, and vitamin B6.
  • Assist food digestion improve enzyme levels, improve bowel regularity.
  • Regulate pH value by producing lactic acid, hydrogen peroxide... they increase the acidity of intestine (lower pH value) and inhibit the reproduction and proliferation of many harmful bacteria and yeasts.
  • Detoxify and protect the intestines.  Lactobacilli tend to combine with toxins such as heavy metals, and carcinogens; they die from toxins and are eliminated (together with the toxins) as solid waste.
  • Reduce cholesterol levels when high.
  • Aid absorption of minerals, especially calcium, due to increased intestinal acidity.
  • Supports immune system.  In one experiment, only 10 bad bacteria (Salmonella) were necessary to kill a guinea pig with an inadequate amount of beneficial bacteria, but about a trillion cells were required to kill an animal with its full natural beneficial microorganisms present.
  • Reduce risks of cancer and certain tumors.
  • Compete with pathogenic bacteria and yeasts for food and space.  In healthy humans, good bacteria and yeast cover the surface of the mucosa and pathogenic bacteria and yeast cannot attach themselves.

Probiotics in powder form can be used for treating oral thrush.

When Candida albicans is killed by fungicide, it will leave the mucosa wall, and be pushed out as solid waste.  Taking probiotics 15min to one hour after taking fungicide will hopefully allow good bacteria to populate the mucosa wall.  The good bacteria will fight the yeast on three ways: it will compete for food with Candida, produce fungicide as hydrogen peroxide and help in digestion of food (alleviating Leaky Gut Syndrome that way).


If supplementation is needed, start by taking at least 1-10 billion viable L. acidophilus or B. bifidum cells daily divided into 3 or 4 doses.  Take them on an empty stomach or at least 30-60 minutes before eating.  Take 15-20 billion viable organisms daily to prevent diarrhea from antibiotic therapy.


When large doses of probiotics are first taken, mild gastrointestinal symptoms may occur and flu-like symptoms may also occur within 3 days.  Symptoms of toxicity from taking probiotics are rare.

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Probiotics can help with the following:


Allergy to Cow's Milk

Oral administration of probiotic bacteria has been shown to stabilize intestinal integrity, promote local IgA production and reduce intestinal inflammation in atopic individuals with cow's-milk allergy.


Bacterial Dysbiosis

How do the friendly bacteria keep the bad bacteria in check?  Think of a crowded theater.  You walk in, and there is no place to sit; all the seats are taken.  So you can't stay.  It is the same with bacteria.  There are only a certain number of "seats" in the colon.  If they're all taken by friendly bacteria, then there's no chance for the bad bacteria to set up shop and start to duplicate themselves.

According to most researchers, normal probiotics should be more numerous than the cells of the intestinal lining itself.  One of the ways to help reestablish a balanced bacterial population in the GI tract is the use of probiotic supplements.  There are many products on the market containing a variety of organisms and a general approach could be taken using a broad spectrum probiotic formula.  However, a better method is to discover the type of imbalance by testing and then supplementing those specific bacteria that are needed.  Bringing these normally-occurring bacteria into balance will help prevent the overgrowth of more pathogenic organisms.

Bifidobacteria are the predominant lactic acid bacteria of the colon with a concentration that is 1000 times higher than Lactobacilli.  Administration of Bifidobacterium breve to humans and animals reduces fecal concentrations of Clostridia and Enterobacter species, ammonia, and toxin-releasing bacterial enzymes including beta-glucuronidase and tryptophanase.  Bacillus laterosporus, a novel organism classified as non-pathogenic to humans, produces unique metabolites with antibiotic, antitumor and immune modulating activity.  This organism is available as a food supplement in the United States.  It has been found to be an effective adjunctive treatment for control of symptoms associated with small bowel dysbiosis in a number of patients.

Fructose-containing oligosaccharides (FOS), found in vegetables like onion and asparagus, have been developed as a food supplement for raising stool levels of Bifidobacteria and lowering stool pH.

Crohn's Disease

Use of a good probiotic product can help keep the bacterial flora in balance and reduce inflammation.  Caution is advised with active inflammation, as bacteria may penetrate the gut wall and enter the blood stream.


A study of hospitalized children showed that a combination of Lactobacillus acidophilus and Bifidobacterium infantis was effective in treating acute diarrhea.  One of the more common causes for hospitalization of infants and young children is dehydration related to acute diarrhea, especially from a rotavirus.

Lactobacilli in the intestines play an important role in developing natural defenses against both intestinal bacterial and viral infections.  In the study group, the frequency of diarrhea improved on the first and second days of hospitalization and the duration of diarrhea during hospitalization also decreased.  The researchers concluded "Oral bacterial therapy is an effective adjuvant therapy in rotavirus positive and negative children with diarrhea and can safely be administered during an episode of acute diarrhea." [Acta Paediatr Taiwan 2001 Sep-Oct; 42(5): pp.301-5]

Ulcerative Colitis

Dr. McCann, originally with Kaiser Permanente in Ohio, has pioneered a dramatic, experimental treatment for inflammatory bowel disease which has induced a rapid remission in 16 out of 20 patients with ulcerative colitis.  A two-day course of multiple broad-spectrum antibiotics to "decontaminate" the gut is followed by administration of defined strains of E. coli, and Lactobacillus acidophilus to produce a "reflorastation" of the colon.  Others have not achieved this same degree of success.  It may need to be combined with the specific carbohydrate diet described in the book Breaking the Vicious Cycle.


Vaginitis/Vaginal Infection

Twice-daily vaginal douches, using 2 teaspoons full of acidophilus/bifidus powder in a quart of warm water, will help treat many recurrent vaginal yeast infections.  Even just taking probiotics orally will increase the colonization of these organisms in the vagina and help prevent infections from occurring.


Immune System Imbalance (TH2 Dominance)

The specific bacteria that help balance a TH2 dominant immune system are:

  • Lactobacillus Plantarum and L casei – potent inducers of IL-12 and IFN-gamma.  They support mucosal immunity.
  • Bifidobacterium longum – increases IgA (supports mucosal immunity) – reduces candida albicans – improves lactose tolerance.
  • Acidophilus – promotes resistance to colonization of candida albicans.

Soil Based Organisms (SBOs) (bacillus subtilis and licheniformis) produce surfactin that inactivates lipid envelope viruses (HIV, CMV, herpes etc), kills mycoplasmas, many bacteria and candida albicans.  By reducing candida albicans, SBOs reduce TH2 cytokines.


Yeast / Candida Infection

The use of probiotics to help keep candidal overgrowth from occurring is a common part of many antifungal programs.


Giardiasis Infection

Probiotics may interfere with giardia infection through a number of mechanisms, including competition for limited adhesion sites; competition for nutrients that would otherwise be utilized by pathogens (e.g. glucose); and stimulation of the immune response.  Orally-administered probiotics have great potential to affect the microflora of the proximal small intestine as this area is sparsely populated when compared to the colon or distal small bowelProbiotic attachment, subsequent growth, and metabolic activity may have dramatic effects on host immune responses and the local micro-ecology.

Probiotics may also directly inhibit giardial growth and induce innate and immunological antigiardial mechanisms.  For example, Lactobacillus johnsonii strain La1 has demonstrated the ability to produce substances that inhibit growth of G. intestinalis in vitro.  Substances found in L. johnsonii La1 supernatant impaired the ability of giardia to replicate and encyst.  The La1 extracellular products have also been found to cause dramatic alterations in the morphology of giardia trophozoites.

Probiotics can also enhance intestinal IgA immune responses and increase intestinal mucin production.  The actions and qualities of probiotics appear to be strain-specific.  Even closely-related bacterial strains within the same species may have significantly different actions.

Taking sauerkraut or kim chi throughout the day is a dietary measure that often helps.

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