Introduction

Billions of bacteria inhabit the intestines, and this intestinal bacteria can be beneficial to the human body in a variety of ways. For example, bacteria aids in digestion by synthesizing vitamins, converting dietary fiber, and degrading dietary toxins. Bacteria also help stimulate the development of the body's immune system. The relationship between good and bad intestinal bacteria is essential to one's health. This is because "inside [the] small and large intestines there are 400 to 500 different species of bacteria that live in synergy, as long as the good bacteria outweigh the bad bacteria. If the balance gets upset and the bad becomes more prevalent, [one] can develop many symptoms and sicknesses. The most immediate effects are excess gas, bloating and diarrhea."(1) When the development of intestinal bacteria "ceases to be regulated, [the bacteria] can proliferate and become pathogenic....The balance between these bacteria, known as commensals, and the immune system controlling them, is therefore essential. Changes in this balance can cause severe intestinal diseases, such as Crohn's disease, or other chronic inflammatory conditions with serious sequelae "(2)

Intestinal Bacteria

"The human intestine maintains within its inner cavity a complex, crowded environment of food remnants and microbial organisms (called "the intestinal flora") from which the body derives nourishment and against which the body must be protected ... Bacteria form the largest segment of the intestinal flora. The number of bacteria in the large bowel...exceeds the number of cells in the human body."(3) It is essential that the correct balance of good and bad intestinal bacteria be maintained. "The relationship between the human host and [intestinal bacteria] is described by the Greek word, symbiosis, which means 'living together'. When symbiosis benefits both parties, it is called mutualism. When symbiosis becomes harmful, it is called dysbiosis."(3) Dysbiosis indicates that an individual's intestinal bacteria is unbalanced (i.e. more bad bacteria than good bacteria).

Typically, the intestines should contain an 85% good bacteria and only 15% bad bacteria.(8) This balance is upset when good bacteria are destroyed and bad bacteria begin to take over. Many factors may contribute to killing off the good bacteria including stress, poor eating habits, sickness, and medication use.(5)

Beneficial Bacteria

"The two main families of friendly flora are lactobacillus, needed in the small intestine, and bifidobacterium, needed in the large intestine. Within these families are species and within that, strains."(1) "There are complex differences among the different strains of [intestinal bacteria]. Individual species can be both beneficial and detrimental depending on a number of factors, including life stage, mutation, location in your body, and presence of other strains. What's most important is not so much the sheer number of bacteria, but the balance among them."(5)

Lactobacillus is a large bacterial genus...[and] bacteria in this genus are generally benign. Lactobacillus bacteria are among a larger classification of bacteria known as lactic acid bacteria because they produce lactic acid as a byproduct when they feed. In the case of Lactobacillus, the bacteria live on sugars, converting them into lactic acid and an assortment of other compounds."(6) "Lactobacillus species are used for the production of yogurt, cheese, sauerkraut, pickles, beer, wine, cider, kimchi, chocolate and other fermented foods....(7)

Like Lactobacillus, Bifidobacterium is also a lactic acid producing bacteria and can be found in fermented foods such as yogurt and cheese. "Lactobacillus and Bifidobacteria maintain a healthy balance of intestinal flora by producing organic compounds. These organic compounds include lactic acid, hydrogen peroxide, and acetic acid that increase the acidity of the intestine and curb the reproduction of many harmful bacteria."(4)

Harmful Bacteria

There are several common types of harmful bacteria, and these include: E. coli, salmonella, rotavirus, giardia and Cryptosporidium. Harmful "bacterial enzymes can inactivate human digestive enzymes and convert human bile or components of food into chemicals which promote the development of cancer. Some by-products of bacterial enzyme activity, like ammonia, hinder normal brain function." It is possible for someone to carry these harmful bacteria without displaying any symptoms at all.(3)

When the harmful bacteria begin to increase and feed on the food particles and other substances in the digestive tract. This often produces toxic by-products that is absorbed into the digestive organs and carried throughout the body by the blood. This can cause numerous symptoms including premature aging, inflammation, and organ failure.(8)

Benefits of Probiotics

The proper balance of bacteria can often be maintained through proper diet and limiting negative factors including stress and illness. In addition to these efforts, probiotics can help increase the body's ability to achieve this balance. While probiotics are contained in many foods, many find that supplements are the best way to introduce them into the digestive system. Many common supplements include probiotics such as Saccharomyces, Lactobacillus acidophilus, and Bifidobacteria. These helpful supplements not only introduce the beneficial bacterias to the body, but also typically contain components that encourage the growth and activity of existing friendly bacterias. These components may include competitive yeasts and prebiotics (substances that help the probiotics survive the passage through the stomach and small intestines).(5)

REFERENCES:

(1) Weiss, J. (2007). The Bacteria You Want in Food. MSN Health and Fitness.
(2) CNRS (2008, November 18). Immune System And Intestinal Bacteria: The Key To Balanced Cohabitation. ScienceDaily.
(3) Galland, L. (1998). Intestinal Parasites, Bacterial Dysbiosis and Leaky Gut. Excerpts from Power Healing. Foundation for Integrated Medicine.
(4) Learn the Benefits of Bifidobacterium. Published by VAXA. Unknown.
(5) Pick, M. (2009.). Probiotics For Life! Digestion and GI Health. Published by Women to Women.
(6) Smith, S.E. (Unknown). What is Lactobacillus? Published by wiseGEEK.
(7) Ljungh, A. and Wadstrom, T. (2009). Lactobacillus Molecular Biology: from Genomics to Probiotics. Caister Academic Press.
(8) What is Useful Bacteria. Published by Desserts-Recipes. Unknown.

For more information:

A complete description of probiotics, along with groundbreaking recent clinical research illustrating the many ways probiotics can prevent disease, can be found in Probiotics - Protection Against Infection: Using Nature's Tiny Warriors To Stem Infection. This new compendium from one of contributing authors of the content on this page, Dr. Casey Adams, PhD., takes the confusion out of selecting and supplementing with probiotics. Referencing over 500 scientific studies and reports, and with detailed instructions on how to make your own probiotic foods, this book is a must for anyone seeking to understand the power of probiotics, and improve their immunity and vitality. Click here for ordering information.

Please read this Disclaimer:
The contents of this site, such as text, graphics, images, information obtained from www.Probiotic.org licensors and other material ("Content") contained on this site is for informational purposes only. The Content is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this site!