Germs to the Rescue

By Trankina, Michele L. | The World and I, December 2002 | Go to article overview

Germs to the Rescue

Trankina, Michele L., The World and I

Populations of friendly bacteria that inhabit the large intestine protect us from attacks by pathogenic agents and alleviate the symptoms of a number of maladies.

Rarely do the words germs and rescue share the same billing. After all, have we not been repeatedly warned that germs are associated with contamination, disease, and unsanitary conditions? True, but we also know that all germs are not the same. In fact, scientists are discovering a growing list of microorganisms that silently contribute to making our world a better place. Many of these microbes are well known in food technology, and they are becoming increasingly conspicuous in the promotion of human health.

These beneficial germs that dwell in our digestive system are also referred to as friendly microflora, natural flora, and probiotics (from the Greek terms that mean "for life"). Rapidly accumulating literature attests to their roles in disease prevention and symptom relief. Over the past 10 years, numerous symposia and international conferences have underscored the clinical significance of probiotics, elucidating their features and potential applications for improving human health.

In defining the term probiotics, people from various disciplines-- particularly microbiology, biochemistry, and nutrition--have introduced their own nuances. Nonetheless, in a broad sense, probiotics may be defined as mixed cultures of live microbes (or products containing them) that, when ingested in sufficient quantity, exert beneficial effects on the health of the host. Probiotic products include fermented dairy and nondairy foods and supplements containing live bacteria, mainly of the genera Lactobacillus and Bifidobacterium.

When a probiotic product is ingested, the microorganisms it contains must be capable of surviving through the harsh conditions that prevail in most of the gastrointestinal (GI) tract. Some of them will eventually inhabit the lower part of the small intestine, while most will settle in the large intestine (colon). The colon is an especially suitable residence because of the relatively slow rate of passage of its contents compared with movement in the small intestine.

When populations of microflora are fully established, an average adult's colon contains upward of 400 species of micoflora, with 1011 bacterial cells per gram of colon contents. It is estimated that 20--40 percent of probiotic bacteria survive after ingestion and take up either permanent or temporary residence, depending on conditions.

Long history of usage

There is a long history of the consumption of fermented foods, along with specific recommendations for treating human illnesses. The Old Testament contains numerous references to eating curds, probably referring to yogurt. A Persian exegesis of Genesis 18:8 offers that "Abraham owed his longevity to the consumption of sour [fermented] milk."

Microbiologists have also long been aware of the importance of microbial homeostasis (balance) in the gut. The person most credited with recognizing the GI benefits of fermented foods is Nobel laureate Elie Metchnikoff of the Pasteur Institute, who ushered in the age of probiotics with his book The Prolongation of Life (1908). Metchnikoff proposed that the marked longevity of Bulgarian peasants was correlated with their intake of yogurt, produced by fermenting milk with microorganisms that generate lactic acid. He theorized that the lactobacilli (lactic acid bacteria) in yogurt kept pathogen populations in the peasants' intestinal tracts in check.

Goran Molin of Sweden's Lund University suggests that the consumption of fermented foods containing lactic acid bacteria was common until well into the twentieth century but then declined, leading to an increased incidence of GI maladies. The reduction of natural flora in the GI tract can also be attributed to several other factors: the widespread ingestion of antibiotics and other drugs by humans and animals raised for human consumption; food sterilization methods; and improvements in hygiene, along with the proliferation of antibacterial products. …

The rest of this article is only available to active members of Questia

Sign up now for a free, 1-day trial and receive full access to:

  • Questia's entire collection
  • Automatic bibliography creation
  • More helpful research tools like notes, citations, and highlights
  • Ad-free environment

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Default project is now your active project.
Project items

Items saved from this article

This article has been saved
Highlights (0)
Some of your highlights are legacy items.

Highlights saved before July 30, 2012 will not be displayed on their respective source pages.

You can easily re-create the highlights by opening the book page or article, selecting the text, and clicking “Highlight.”

Citations (0)
Some of your citations are legacy items.

Any citation created before July 30, 2012 will labeled as a “Cited page.” New citations will be saved as cited passages, pages or articles.

We also added the ability to view new citations from your projects or the book or article where you created them.

Notes (0)
Bookmarks (0)

You have no saved items from this article

Project items include:
  • Saved book/article
  • Highlights
  • Quotes/citations
  • Notes
  • Bookmarks
Cite this article

Cited article

Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)


1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25,

Cited article

Germs to the Rescue


Text size Smaller Larger Reset View mode
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Full screen

matching results for page

Cited passage

Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25,

Cited passage

Welcome to the new Questia Reader

The Questia Reader has been updated to provide you with an even better online reading experience.  It is now 100% Responsive, which means you can read our books and articles on any sized device you wish.  All of your favorite tools like notes, highlights, and citations are still here, but the way you select text has been updated to be easier to use, especially on touchscreen devices.  Here's how:

1. Click or tap the first word you want to select.
2. Click or tap the last word you want to select.

OK, got it!

Thanks for trying Questia!

Please continue trying out our research tools, but please note, full functionality is available only to our active members.

Your work will be lost once you leave this Web page.

For full access in an ad-free environment, sign up now for a FREE, 1-day trial.

Already a member? Log in now.