What Is Bifidobacterium Longum?

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The human digestive tract is home to a large and dynamic microbial habitat which consists of over 500 different species of bacteria. These "healthy" or "good" bacteria serve a variety of purposes from digesting foods to preventing disease. Bifidobacterium longum is one of the most abundant species of bacteria in the digestive tract and also one of the most popular probiotics.

Bifidobacterium Longum

Bifidobacterium longum is a specific species of microscopic non-pathogenic bacteria found naturally in the gastrointestinal tracts of humans as well as in most other animals. It is added to a variety of foods or dietary supplements as a probiotic due to its many health benefits. It is a gram-positive, branched rod-shaped bacterium that produces lactic acid from the fermentation of sugar in the gastrointestinal tract.


Defining Probiotics

Probiotics are live microorganisms, which, when administered in adequate amounts, confer a health benefit on the host. They include a wide variety of bacteria and other microorganisms found naturally in the digestive tract with species belonging to the genus Bifidobacterium and Lactobacillus being the common. Probiotics are available as dietary supplements and are commonly added to foods such as yogurt, juices and milk and soy products. Probiotics have undergone numerous research studies with the greatest evidence supporting their benefit for the treatment of diarrhea and other ailments of the digestive tract, prevention of urinary tract infections, immune system support and prevention of certain cancers of the gastrointestinal system, according to the National Center for Complementary and Alternative Medicine.


Health Benefits

Bifidobacterium longum provides many health benefits as a naturally-occurring bacterium and as a probiotic. The lactic acid produced by the bacteria increases the acidity of the digestive tract, which helps inhibit the growth of harmful bacteria. Bifidobacterium longum also has been shown to treat constipation, reduce inflammation associated with inflammatory bowel conditions, prevent high cholesterol levels and reduce the development of certain allergies, according to probiotic.org. According to a study in the April 1997 issue of "Carcinogenesis," Bifidobacterium longum showed anticarcinogenic and antimutagenic properties and may help inhibit the development of colon cancer. Probiotic supplements are also beneficial in repopulating Bifidobacterium longum colonies in the digestive tract that have been destroyed by antibiotic use.



Probiotics like Bifidobacterium longum are generally regarded as safe for the majority of individuals, but more research is needed to determine the safety profile for children, the elderly and individuals with a weakened immune system, according to the National Center for Complimentary and Alternative Medicine. Side effects of probiotic use are rare with the most common being gastrointestinal upset, but more serious side effects could occur such as immune system modulation, changes in the metabolic activity of cells and the transfer of genetic material into host cells. Also, as dietary supplements, probiotics are not regulated by the FDA and as such, label claims concerning the amount or type of probiotic present in the supplement may not be accurate.