Probiotics

Definition

Probiotics, as defined by the Food and Agricultural Organization of the United Nations (FAO), are "live microorganisms administered in adequate amounts which confer a beneficial health effect on the host." The microorganisms referred to in this definition are non-pathogenic bacteria (small, single celled organisms which do not promote or cause disease), and one yeast, Saccharomyces. They are considered "friendly germs," due to benefits to the colon and the immune system. The word probiotic is a compound of a Latin and a Greek word; it means "favorable to life." Probiotics is also sometimes used to refer to a form of nutritional therapy based on eating probiotic foods and dietary supplements. Although probiotic supplements have also been used with farm animals, most are produced for human consumption in the form of dairy products containing two types of microbes—lactobacilli and bifidobacteria. As with the extended use of royal jelly, probiotics are now also being used in face creams and similar cosmetic products.


A new category called prebiotics now also appears in the literature. Prebiotics refer mainly to certain foods, and occasionally to certain food products, that support probiotic microorganism viability, enhancing their survivability. Included among prebiotics are foods such as Jerusalem and regular artichokes, oats, leeks, onions, and whole grain breads or cereals. Examples of prebiotic food products are the Fructooligosaccharides (fructooligo-saccharides, or fruit derived, digestion resistant sugars) (FOS), also in honey, and the galactooligosaccharides (galacto-oligo-saccharides), sugars in galactose-containing foods like goats milk.

One of the chief difficulties in benefiting from probiotic supplementation has been assuring survivability of the bacteria as it passes through the acidity of the stomach and the digestive processes of the small intestine and successfully colonizing in the colon. Recently, a new probiotic with exceptional survivability and colonization characteristics, as demonstrated in studies, has emerged. This probiotic, screened from many strains of lactobacilli and named after its co-discoverers, Sherwood Gorbach and Barry Goldin, is known as Lactobacillus GG (LGG). LGG was demonstrated effective against psuedomembranous colitis, an infection of the colon by Clostridium difficile as a result of antibiotic overkill of beneficial bacteria, and against atopic eczema in children due to gut permeability. LGG was demonstrated to have positive results against Candida in mice, as well. Three patents have been awarded on LGG from June 1989 to May 1995. In 1987, a Finnish dairy cooperative, Valio, Ltd., was granted a license to conduct research. About 1992, Valio released a fermented milk product with LGG called Gefilus. In 1996, a division of an American corporation was formed, called CAG Functional Foods, which markets LGG as the product Culturelle. One source reported significant benefit from the use of Culturelle when cultured in milk. Culturelle is currently available only in capsules, but a yogurt product is anticipated to be marketed soon.


Much of the research and marketing of proven probiotics is conducted outside the United States. One such research proven probiotic strain is Lactobacillus plan-tarum 299v. It has been particularly valuable in irritable bowel syndrome (IBS) and recovery from surgery. It's colonization ability was proven using biopsy. It is not currently available in the United States, but agreements with the makers and distributors of Danon yogurt may change that.


Two proven beneficial strains marketed in the United States are Lactobacillus reuteri, a Swedish product proven effective against diarrhea in children due to a rotavirus (a virus transmitted from feces), available in the Stoneyfield brand of yogurt, and Saccharomyces boulardii, a yeast product available in capsules effective against antibiotic associated diarrhea.


 

Lifestyle-related disorders

Some supporters of probiotics go beyond applications limited to treatment of intestinal disorders. In keeping with the theory of autointoxication, they maintain that probiotics are effective in treating a wide range of chronic and acute illnesses thought to result from a condition called intestinal dysbiosis, or poor intestinal health quality due to toxic buildup, putrefaction, and leaky gut syndrome. Intestinal dysbiosis is defined as an imbalance among the various microorganisms in the digestive tract. This imbalance is attributed to a combination of Western high-protein diets, stress, environmental pollution, and allopathic medications. Putrefaction is believed to result from a low fiber diet, chronic constipation or sluggish colon, and poor food combining leading to increased gut fermentation. Leaky gut syndrome is the term used to suggest that the effect of these toxins on the intestinal cell walls is damaging to intestinal integrity, and as a result, large molecules of relatively undigested food and toxins cross the intestinal membrane into the blood stream.


Some alternative practitioners maintain that the following diseases and disorders are directly related to intestinal dysbiosis or may also be beneficially treated with probiotics:

•mental health problems

•chronic fatigue syndrome

•muscular soreness and stiffness

•autoimmune disorders, including lupus, rheumatoid arthritis, ankylosing spondylitis, enteric arthritis, and Reiter's syndrome (by immune stimulation and repair of the leaking gut)

•lactose intolerance (by increasing the presence of lactase)

•infectious diseases

•high blood pressure (research has demonstrated a systolic blood pressure decrease of 10–20 mm Hg with the use of a fermented milk product

•high cholesterol, (clinical studies have not been conclusive; as one source said, "Evidence is not over-whelming")

•cancer (by decreasing exposure from gene-altering substances)

•menopausal problems in women (by improving the liver's ability to detoxify and eliminate hormonal metabolites)

•vaginosis (once thought to be relatively benign, now implicated in easier transmission of sexual diseases, pelvic inflammatory disease, and pregnancy-related complications, improved by reducing vaginal pH which inhibits growth of unfavorable bacteria)

•allergies and asthma (a double-blind placebo-controlled study demonstrated a 50% drop in children followed up to two years of age)

•kidney stones, by inhibiting the absorption of oxalate from the intestines


 

Products

Probiotics is a nutrition-based therapy and relies primarily on the addition of foods or supplements containing friendly bacteria to the diet. Some recommended foods are ordinary grocery store items that involve fermentation in their production; these include miso, pickles, sauerkraut and fermented dairy products such as yogurt and kefir. As mentioned, other food or food products called prebiotics, such as Jerusalem artichokes and FOS, are thought to support the growth of the beneficial bacteria in the intestines. Most users and recommenders of probiotics, however, encourage the use of loose powdered, refrigerated dietary supplements of friendly bacteria or LGG capsules. Some of these products are milk-based, while others are milk-free. Probiotic dietary supplements are over-the-counter (OTC) preparations that can be easily purchased at grocery or health food stores, or from European manufacturers over the Internet. The types of bacteria most often recommended are Lacto-bacillus GG, Lactobacillus acidophilus, Lactobacillus bulgaricus, and, especially for children Bifidobacterium bifidum. Breast milk is reported to contain nutrients that support bifidobacterium growth.

Dosage and administration

Some practitioners distinguish between a therapeutic dose of probiotic products, which is given for 10 days, and a maintenance dose, which is used afterward. One source gives 2–5 level tsp (5–10 g) of powdered supplement as the daily therapeutic dose if the patient is taking L. acidophilus or B. bifidum, 1–3 tsp (3–6 g) if the patient is using L. bulgaricus. The maintenance dose of L. acidophilus is given as 0.5 tsp (1 g) daily; of B. bifidum, 2 tsp (4 g) daily; of L. bulgaricus, 0.5 tsp (1 g) with each meal. The recommended dose of LGG capsules is once daily. A dose two or three times daily may also be used initially to overcome acute symptoms.


Patients are advised to take these supplements with spring water, but not with juice or broth. These fluids are thought to stimulate the secretion of stomach acids that will destroy the friendly bacteria.


 

Side effects

The side effects of treatment with probiotics may include a condition called excessive drainage syndrome, which includes headache, diarrhea, bloating, or constipation. Another commonly reported side effect is intestinal gas. These side effects are attributed to the cleansing of toxins from the body and may last for some days. Practitioners recommend lowering the supplement dosage to reduce the side effects, or pretreating with colonic therapy, or stool softeners and fiber as tolerated or advised by a healthcare professional.

Research & general acceptance

More studies of probiotics have been done in Europe than in the United States, which is reflected in the fact that the leading manufacturers of probiotic supplements are presently based in Europe. Some mainstream researchers in Europe as well as in the United States are skeptical of some of the claims made for probiotics. Their reasons include the following considerations:

•The studies done in support of probiotics are mostly anecdotal or heavily reliant on test-tube experimentation rather than on clinical trials in human subjects. As of 2000, relatively few strains of probiotic bacteria have been shown to have clinical value. These strains are helpful in treating milk allergy and irritable bowel syndrome in humans, and in improving resistance to a yeast called Candida in immunocompromised mice.

•The basic concept of probiotics is based on a misunderstanding of the role of microflora in the human digestive tract.

•It is difficult to see how bacteria taken by mouth can survive the process of human digestion. At present, only two species of lactobacilli, L. GG and L. plan-tarum 299v, have been shown to be able to colonize the human gut.

•Supporters of probiotics emphasize two types of bacteria, the lactobacilli and the bifidobacteria, and virtually ignore the hundreds of other species that live in the intestines.


More clinical studies examining the effects of probiotics on specific conditions are being conducted. One such study in the making will examine the effect of probiotics on hepatic steatosis, or fatty degeneration of the liver. An inclusion criteria was biopsy diagnosis of non-alcoholic fatty liver disease. The study is expected to be completed in October 2004.

 

Best Food Sources for Probiotics

 

Swallowing a beverage full of bacteria probably doesn't sound appetizing, but according to evidence cited by the Harvard Medical School, a type of bacteria called lactobacillus could treat gastrointestinal conditions such as infectious diarrhea and irritable bowel syndrome. Now called probiotic therapy, researchers believe it has the potential to treat gastrointestinal problems that otherwise fail to respond to traditional medical treatments. It isn't hard to get your daily dose of probiotics either. They come in supplement form, and many foods are naturally rich with lactobacillus bacteria, helping keep your gut healthy. Here's how to get your fill.


 

Probiotics: Myths and Facts


Most people think of bacteria as bad. That's because some bacteria are linked with infection and disease. But there's a growing interest in "good" bacteria called probiotics. These bacteria live peacefully inside your intestines, where they feed off of carbohydrates and fiber that your body can't completely digest. By taking up residence in your intestines, they make it more difficult for disease-causing bacteria to move in. This creates a healthier environment inside your stomach.


There's still much to learn about these gut-friendly bacteria. Plus, there are lots of myths and misconceptions about probiotics, what they do, and the best way to get their benefits. Here are some of the most common ones dispelled.


Myth: Yogurt is the best source of probiotic bacteria

Fact: Yogurt may be a good source of probiotic bacteria—but not always. Some yogurt has been heat-treated to temperatures that probiotic bacteria can't survive. Even for yogurt that hasn't been heat-treated you don't know how many active probiotic cultures it contains. Look for a yogurt labeled "active or live cultures." This means it hasn't been heat-treated and contains probiotic bacteria.


Myth: Yogurt is the only source of supplemental probiotics

Fact: Yogurt is only one source of probiotic bacteria. Fermented foods like miso, tempeh, fermented cheeses, Korean kimchee, kefir, and acidophilus milk are other good sources. Sauerkraut is also a source, but canned sauerkraut has been heat-treated and probably doesn't have a significant number of probiotic strains. If you make your own sauerkraut at home, it can be a very good source of good bacteria. You can also get probiotics by taking a probiotic supplement.


Myth: All probiotic bacteria are the same in terms of their benefits

Fact: There are hundreds of types of probiotic bacteria, and different strains of probiotic bacteria have different health benefits. The problem is the distinct benefits of each strain of probiotic bacteria haven't been categorized at this point. That means it's best to get a diverse mix of probiotic bacteria until more is known about the role each bacteria plays and what the distinct health benefits of each are.


Myth: Probiotic supplements are a "sure-fire" way to get the probiotics you need for health


Fact: Consumer Reports tested probiotic supplements and found the ones they tested contained fewer active probiotic strains than what you could get from yogurt with active cultures. Plus, there's little regulation of the supplement industry. What's printed on the label may not be what you're actually getting. The same goes for food products you buy in the supermarket that are "fortified" with probiotics, like cereals and juices.


Myth: Probiotics can prevent or treat a number of diseases

Fact: Probiotic research is still in its infancy, but preliminary studies suggest that probiotics are beneficial for treating infectious diarrhea, diarrhea resulting from antibiotic use, irritable bowel syndrome, and possibly atopic dermatitis in babies. There's also some evidence they may reduce the frequency of colds and may be helpful for treating vaginal yeast infections and inflammatory bowel disease, but it's too early to say.


Myth: Probiotic supplements are safe for everyone

Fact: Probiotic supplements appear to be safe if you have a healthy, functioning immune system. If you have an immune-deficiency disease, check with your doctor first. Some medications like steroids and cancer chemotherapy drugs cripple the immune system. Taking probiotics while on these medications could increase your risk for illness.


If you're on a medication that suppresses your immune system, avoid probiotic supplements unless your doctor gives the OK. It's also not clear whether they're safe for young children, the elderly, or pregnant women. Some people also experience mild intestinal upset and bloating when they take probiotic supplements.


The Bottom Line?

Probiotics appear to have benefits, but there's a lot of misinformation out there. Keep these guidelines in mind when considering their potential benefits.