The friendly microbes known as probiotics come in a variety of species.
Probiotics, the beneficial micro-organisms that are normally found in the human body, have been available in health food stores for decades. Featuring Lactobacillus acidophilus and Bifidobacteria bifidum, which occur naturally in the large intestine, probiotic supplements were generally thought of as a simple aid to digestion.
That view of the probiotic universe has become as outdated as bell bottoms and mood rings. For one thing, scientists have discovered a number of beneficial microbes occupying niches all along the gastrointestinal tract. Probiotics also provide benefits that go far beyond their digestive effects.
From Stem to Stern
Probiotic bacteria are usually seen as denizens of the large intestine. It’s true that a healthy colon harbors hundreds of beneficial species (amounting to trillions of individual organisms) while some sections of the gastrointestinal tract, most notably the stomach and upper small intestine, do not provide an ideal probiotic environment. But we now know that other parts of the digestive system are inhabited by their own specialized colonies of healthful microbes.
Probiotic activity actually starts in the mouth and upper airway, where S. salivarius K12 resides. Scientists have found higher levels of this organism in people who tend to resist developing sore throats. K12 has shown an ability to fight inflammation; it also produces proteins that appear to target disease-causing bacteria. In addition, the mouth contains another S. salivarius strain known as M18, which has been found to reduce plaque buildup and help prevent cavities.
The lower small intestine, the part that connects to the large intestine, plays host to its own probiotic community. One of the organisms found there, Lactobacillus sporogenes (also called Bacillus coagulans), has shown an ability to fight destructive free radicals.
Better Digestion and More
Probiotics help synthesize vitamins and allow the body to more readily absorb other nutrients, particularly minerals. They protect the digestive tract’s mucosal barrier and inhibit the growth of harmful bacteria. And probiotics help keep a potentially troublesome yeast called Candida albicans, a common cause of vaginal and other infections, in check. These actions help explain why probiotic supplements have improved quality of life and spurred weight loss after gastric bypass operations (Journal of Gastrointestinal Surgery 7/09).
What’s more, probiotics help regulate immune function. Nearly 80% of all immune cells in the body reside within the intestines, where they defend against harmful bacteria. Probiotics not only help stimulate the immune system when needed but also help tone down an excessive immune response.
A number of researchers believe that probiotics can play an important role in neutralizing both respiratory and skin allergies (Annals of Allergy, Asthma & Immunology 11/08 and 12/08).
The body’s delicate probiotic balance can be upset by illness, stress, poor diet and drug treatments. This is especially true of antibiotics, which can kill good bacteria along with the bad, leading such side effects as diarrhea. The use of supplemental probiotics has been found to help reduce these intestinal discomforts (Journal of Medical Microbiology 5/09). In this case, the supplement should
be taken at least an hour after the medication for maximum effectiveness.
Supplemental probiotics need to contain enough live organisms to be effective; the manufacturer should supply an independent lab verification of viability. A quality product should also provide a prebiotic, a substance that feeds the microbes, such as that found in açai pulp.
Improved digestion is still a valid reason to take probiotics. But given all their other benefits, it certainly isn’t the only reason.