An Introduction To The World Of Probiotics: Have You Had Your Friendly Bacteria Today?
CAPSULE REPORT: While not specifically an organic foods topic, probiotics is a health and wellness issue that you’ll be hearing more about as manufacturers market more “functional foods” to Americans interested in the promise of health without having to do more than eat. Thanks to Dannon, Americans have been exposed to more than $200 million of advertising that says probiotics are important to digestive health. This thorough report by Stephanie Zonis explains the state of probiotics today, so that when you see that container of yogurt “With Probiotics” and a string of “probiotic bacteria” on the ingredients label, you can decide if it makes a difference to you. This is Part I of a seven-part article. Use the article index below to click among the sections.
The first step is to define probiotic. What is probiotic food? Is it all about probiotic yogurt? Are probiotic cultures different from other yogurt cultures? What other probiotic products should you consider?
Probiotics-a word few people had heard a year ago-now rank among the top five foods* that people say they want to add to their diets, according to the NPD Group, a Chicago-based company that tracks consumer trends. And despite the growing popularity and willingness to pay more for probiotic foods, most people don’t know what probiotics are. While buttermilk, kefir and yogurt traditionally contain “friendly” bacteria, probiotics go further: They contain strains of bacteria that deliver health benefits when eaten regularly and in high enough quantities. Spend a few minutes here today, and you’ll experience a mini-seminar on these friendly microbes.
*The others, in order of preference, are whole grains, dietary fiber, antioxidants and omega-3 fatty acids.
What Are Probiotics?
It may come as a surprise, but not all bacteria are bad for you. It’s common to hear news reports about harmful bacteria (pathogens) these days, and most of us are familiar with some of their names-Listeria moncytogenes, Clostridium botulinum and various strains of Salmonella, for instance. But other families of bacteria are not injurious to human health, and may, in fact, provide some health benefits, particularly those in the Lactobacillus and Bifidobacterium genera. Probiotic means “for life.” The definition of a probiotic has changed over time, but these days, the generally accepted definition is the one issued by the Food and Agricultural Organization (FAO) of the United Nations and the World Health Organization (WHO). Probiotics are “live microorganisms which when administered in adequate amounts, confer a beneficial health effect on the host.” These microorganisms do not promote or cause disease. They comprise multiple species and subspecies of bacteria, as well as one species of yeast, Saccharomyces, but note that not all live, non-pathenogenic microorganisms are probiotics.
Probiotics are just beginning to catch on in the U.S., but they’ve been a bigger deal in Europe and Asia for years. For instance, Dannon’s Activia, a recent introduction in the U.S., has been sold overseas since 1987. Considering that people of other nations tend to turn to foods and natural remedies for good health, while Americans rely far more heavily on pills and medications, this is not surprising. In fact, according to the International Probiotics Association, Japanese grocery store shelves are stocked with dozens of probiotic-containing foods, while in Europe, yogurts and fermented milks are the most widely-consumed probiotic products. In the U.S., consumption of probiotic supplements far outweighs consumption of foods containing these beneficial bacteria.
In 2007, Dannon’s Activia, sold for 20 years in
Europe, became the first big probiotic brand
Due to the vast number of cells involved in probiotics, counts for these bacteria in any product tend to be very high, often numbering in the billions. While many foods containing probiotics do not list specific bacterial counts, it isn’t uncommon to see numbers of five to ten billion associated with a single serving of probiotic-containing foods. In general, numbers of probiotic bacteria are expressed as a CFU count.
CFU stands for “colony forming unit.” A CFU is a viable cell. Viable cells are live cells that have been rendered dormant and must be reactivated after ingestion on their journey toward the intestinal tract. Consumers are likely to find viable cells in freeze-dried powders that might be in probiotic capsule supplements, for example; live cells are often found in probiotic-containing dairy foods.
You may also see the terms “prebiotics” and “synbiotics.”
Prebiotics are indigestible ingredients in foods that are thought to assist the growth and/or activity of certain probiotics, especially those in the bifidobacteria family. Two of the more commonly-found prebiotics are inulin and fructo-oligosaccharides (FOS).
Synbiotics are supplements or functional foods that contain both a prebiotic and a probiotic (a functional food is one that may provide a health benefit beyond basic nutrition; the concept is based on the ancient Hippocratic concept of food as medicine). The thought is that there are certain combinations of prebiotics and probiotics that can work together especially well.
Neither prebiotics nor synbiotics is covered in this article.
A Very Brief History of Probiotics
Ilya Ilyich Metjnikov (his name is often seen as Elie Metchnikoff, the French spelling) (1845-1916), Nobel Prize winner for his pioneering work on phagocytes, is usually credited with being the first scientist to describe the effects of probiotics, although the term “probiotics” itself was not coined until 1965. Metjnikov wrote a book called Prolongation of Life, in which he identified the “autointoxication” caused by gut bacteria as a chief culprit in human aging.
According to Gerald W. Tannock, Metjnikov postulated that “the bacterial community residing in the large bowel of humans was a source of substances toxic to the nervous and vascular systems of the host. These toxic substances, absorbed from the bowel and circulating in the bloodstream, contributed to the aging process.” Metjnikov’s initial corrective measure for preventing this apparent bacterial decay was to suggest removal of the large bowel! A remedy that met with more approval and was less dramatic involved trying to lessen or replace the “putrefactive bacteria in the intestine.” It was thought that “oral administration of cultures of fermentative bacteria would implant the beneficial bacteria in the intestinal tract.” Since it had been observed that bacteria producing lactic acid prevented milk from putrefying, it was believed that the same bacteria might have a similar effect on the digestive tract.
Ilya Ilyich Metjnikov, a.k.a. Elie Metchnikoff. A museum-quality print is available from Art.com.
Metjnikov had supposedly seen great longevity accompanied by robust health in certain Eastern Europeans who consumed fermented dairy products on a daily basis. This was taken as proof that lactic-acid-producing bacteria worked as Metjnikov predicted they would, and milk inoculated with the so-called “Bulgarian bacillus” enjoyed a wave of popularity in Western Europe. But Metjnikov’s observations and his book were products of the early 1900s, a time when record-keeping in many areas of the world was not nearly as precise as it is today. Documentations of births and deaths could be sketchy, especially in remote areas; exact ages were not always known. In addition, Eastern Europeans weren’t the only ones to have been eating probiotic-containing foods for centuries. Peoples all over the world have been consuming fermented products for a very long time, whether it’s been the kimchi that is ubiquitous in Korea, or the koumiss of the nomads of the Steppes. And no one’s making any claims that Koreans are healthier than anyone else, or that the roaming herders of the treeless plains of southeastern Europe had longer lifespans than do today’s residents of industrialized nations.