Betty Kovacs, MS, RD

PROBIOTICS

Author:

Betty Kovacs, MS, RD

Betty Kovacs, MS, RD

Betty is a Registered Dietitian who earned her B.S. degree in Food and Nutrition from Marymount College of Fordham University and her M.S. degree in Clinical Nutrition from New York University. She is the Co-Director and Director of nutrition for the New York Obesity Research Center Weight Loss Program.

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Medical Editor:

Melissa Conrad Stöppler, MD

What are probiotics?

Let's start with the facts behind what probiotics are. The root of the wordprobiotic comes from the Greek word pro, meaning "promoting" and biotic, meaning "life." There is some debate about how to define probiotics. The Food and Agriculture Organization of the United Nations (FAO) defines probiotics as "live microorganisms, which, when administered in adequate amounts, confer a health benefit on the host." Yes, they are actually alive, and most of these microorganisms are bacteria. Most people think of antibiotics and antibacterial products when you mention bacteria. Both of those kill bacteria so why would you want to consume anything that has live bacteria in it? It's all about balance.

Our digestive system normally has what we would call "good" bacteria and "bad" bacteria. Maintaining the correct balance between the "good" bacteria and the "bad" bacteria is necessary for optimal health. Things like medications, diet, diseases, and your environment can upset that balance

What is the gut?

A "gut feeling" or a "gut reaction" to something is a description of a sense you have about it without knowing why. This probably comes from the fact that many people experience their emotions in their stomach or gut area. Think about where you would physically feel a "gut feeling." Research has shown that the network of neurons lining our guts is so extensive that is has now been nicknamed our "second brain" or "other brain." This gut "brain" doesn't think for us, but it does play a key role in certain diseases and communicates with the brain in our skulls.

Our "second brain" is known as the enteric nervous system. It is a collection of neurons in the gastrointestinal tract. Its role is to manage every aspect of digestion in all the organs of the gastrointestinal tract, including the esophagus, stomach, small intestine, and colon. It uses over 100 million neurons and some of the same chemicals things that can be found in your "other" brain, including neurotransmitters and neuropeptides.

Within your gastrointestinal tract, there is intestinal microflora or microbiota. This complex ecosystem contains over 400 bacterial species. Small amounts can be found in your stomach and small intestines, but the majority is found in your colon. The intestinal microflora aid in digestion, synthesize vitamins and nutrients, metabolize some medications, support the development and functioning of the gut, and enhance the immune system.

What are the health benefits of probiotics?

Probiotics may seem new to the food and supplement industry, but they have been with us from our first breath. During a delivery through the birth canal, a newborn picks up bacteria from his/her mother. These good bacteria are not transmitted when a Cesarean section is performed and have been shown to be the reason why some infants born by Cesarean section haveallergies, less than optimal immune systems, and lower levels of gut microflora.

Probiotics are believed to protect us in two ways. The first is the role that they play in our digestive tract. We know that our digestive tract needs a healthy balance between the good and bad bacteria, so what gets in the way of this? It looks like our lifestyle is both the problem and the solution. Poor food choices, emotional stress, lack of sleep, antibiotic overuse, other drugs, and environmental influences can all shift the balance in favor of the bad bacteria.

When the digestive tract is healthy, it filters out and eliminates things that can damage it, such as harmful bacteria, toxins, chemicals, and other waste products. On the flip side, it takes in the things that our body needs (nutrients from food and water) and absorbs and helps deliver them to the cells where they are needed.

The idea is not to kill off all of the bad bacteria. Our body does have a need for the bad ones and the good ones. The problem is when the balance is shifted to have more bad than good. An imbalance has been associated with diarrhea, urinary tract infections, muscle pain, and fatigue.

The other way that probiotics help is the impact that they have on our immune system. Some believe that this role is the most important. Our immune system is our protection against germs. When it doesn't function properly, we can suffer from allergic reactions, autoimmune disorders (for example, ulcerative colitis, Crohn's disease, and rheumatoid arthritis), and infections (for example, infectious diarrhea, Helicobacter pylori, skin infections, and vaginal infections. By maintaining the correct balance from birth, the hope would be to prevent these ailments. Our immune system can benefit anytime that balanced is restored, so it's never too late.

What are the different types of probiotics?

Probiotic products contain bacteria and/or yeasts that assist in restoring the balance in our gut. Up until the 1960s, the gut microflora that they were able to identify was clostridia, lactobacilli, enterococci, and Escherichia coli. Since then, innovative techniques have discovered many more bacteria.

There are several different kinds of probiotics, and their health benefits are determined by the job that they do in your gut. Probiotics must be identified by their genus, species, and strain level. Here is a list of probiotics and their possible health benefits.

1. Lactobacillus

There are more than 50 species of lactobacilli. They are naturally found in the digestive, urinary, and genital systems. Foods that are fermented, like yogurt, and dietary supplements also contain these bacteria. Lactobacillus has been used for treating and preventing a wide variety of diseases and conditions.

Some of the lactobacilli found in foods and supplements are Lactobacillus acidophilus, L. acidophilus DDS-1, Lactobacillus blugaricus,Lactobacillus rhamnosus GG, Lactobacillus plantarium, Lactobacillus reuteri,Lactobacillus salivarius, Lactobacillus casei, Lactobacillus johnsonii, and Lactobacillus gasseri.

More research is needed regarding probiotics and their potential health benefits before any definitive claims can be made about their effects. However, studies have shown some benefits linked to Lactobacillus and treating and/or preventing yeast infections, urinary tract infection, irritable bowel syndrome, antibiotic-related diarrhea, traveler's diarrhea, diarrhea resulting from Clostridium difficile, treating lactose intolerance, skin disorders (fever blisters, eczema, acne, and canker sores), and prevention of respiratory infections. More specifically, results from some of the studies are as follows:

• Lactobacillus GG was given to children 5 to 14 years of age with irritable bowel syndrome over eight weeks' time. They were given 3 billion cells twice per day. This reduced the frequency and severity of abdominal pain.
• Lactobacillus GG was given to children taking antibiotics and there was a decrease in reported diarrhea.
• Lactobacillus casei, Lactobacillus bulgarius, and Streptococcus thermophilus given twice daily during antibiotic treatment and for a week later decreased the risk of diarrhea in hospitalized adults.
• Lactobacillus GG-containing milk was given to children 1 to 6 years of age who attended day care. They got fewer or less severe lung infections than those who did not drink it.
• Lactobacillus gasseri and Lactobacillus rhamnosus vaginal capsules lengthened the time in between bacterial vaginosis infections.
• Lactobacillus GG reduced the risk of traveler's diarrhea by 47% in a study with 245 people who traveled to 14 worldwide geographic regions.

2. Bifidobacteria

There are approximately 30 species of bifidobacteria. The make up approximately 90% of the healthy bacteria in the colon. They appear in the intestinal tract within days of birth, especially in breastfed infants.

Some of the bifidobacteria used as probiotics are Bifodbacterium bifidum,Bifodbacterium lactis, Bifodbacterium longum, Bifodbacterium breve,Bifodbacterium infantis, Bifodbacterium thermophilum, and Bifodbacterium pseudolongum.

As with all probiotics, more research is needed to prove a definitive benefit, but studies have shown that bifidobacteria can help with IBS, dental cavities, improved blood lipids, and glucose tolerance.

• Bifidobacterium infantis 35624 was given to 362 patients with irritable bowel syndrome in a four-week study. They showed improvement in the symptoms of abdominal pain, bloating, bowel dysfunction, incomplete evacuation, straining, and the passage of gas.
• Salivary levels of bifidobacteria are associated with dental cavities in adults and children.
• Bifidobacterium lactis Bb12 is reported to have beneficial effects on metabolism, including lowered serum LDL-cholesterol in people with type 2 diabetes, increased HDL in adult women, and improved glucose tolerance during pregnancy.

3. Saccharomyces boulardii

This is also known as S. boulardii and is the only yeast probiotic. Some studies have shown that it is effective in preventing and treating diarrhea associated with the use of antibiotics and traveler's diarrhea. It has also been reported to prevent the reoccurrence of Clostridium difficile, to treat acne, and to reduce side effects of treatment for Helicobacter pylori.

4. Streptococcus thermophilus

This produces large quantities of the enzyme lactase, making it effective, according to some reports, in the prevention of lactose intolerance.

5. Enterococcus faecium

This is normally found in the intestinal tract of humans and animals.

a. E. faecium SF68
b. E . faecium M-74

6. Leuconostoc

This has been used extensively in food processing throughout human history, and ingestion of foods containing live bacteria, dead bacteria, and metabolites of these microorganisms has taken place for a long time.

What foods contain probiotics?

Fermented dairy products have been advertised as containing "beneficial cultures." These cultures are what would now be considered probiotics. Other foods currently claiming to provide probiotics are cereal, juice, frozen yogurt, granola, candy bars, and cookies. While they may contain probiotics, there is no guarantee that they have them in the amount or in the form that is necessary to get the health benefits you are looking for. Only the manufacturer of the product can tell you if there are any studies to support their specific product.

What are the side effects and risks of probiotics?

Supplements are not monitored in the U.S. the way that food or medication is. They fall under the Dietary Supplement Health and Education Act of 1994 (DSHEA). This requires that the dietary supplement or dietary ingredient manufacturer be responsible for ensuring that a dietary supplement or ingredient is safe before it is marketed. The only time that the U.S. Food and Drug Administration (FDA) may get involved is if action is needed to be taken against a manufacturer after the supplement is marketed and then found to be unsafe. This means that as much as we may know about probiotics, we can't be certain of the safety or content of the supplements available to us.

There is one Voluntary Certification Program by which a supplement manufacturer can choose to be evaluated. ConsumerLab.com (CL) is the leading provider of independent test results and information to help consumers and health care professionals identify the best quality health and nutrition products. Products that have passed their testing for identity, strength, purity, and disintegration can print the CL Seal of Approval on their product. This is one step toward being confident that you are getting the amount and type of probiotic promised by the manufacturer.

While some studies have shown many health benefits of probiotics, more research still needs to be done to be sure that they are safe and effective as a supplement and in foods. This is especially true for children, pregnant women, elderly people, and people with compromised immune systems. For people with suppressed immune systems due to disease or treatment for a disease (such as cancerchemotherapy), taking probiotics may actually increase your chances of getting sick. Always speak with your doctor before taking any supplement under these circumstances

How should people take probiotics?

The requirements for a microbe to be considered a probiotic are that the microbe must be alive when administered, it must be documented to have a heath benefit, and it must be administered at levels to confer a health benefit. These are live microorganisms that will not provide the promised benefits if they don't stay alive. The manufacturer and consumer must pay close attention to the conditions of storage at which the particular microorganism will survive and the end of their shelf life. The potency will tell you the number of viable bacteria per dose, and the purity has to do with presence of contaminating or ineffective bacteria.

The other thing to remember is that these microorganisms are not all created equally. In fact, the genus, strain, and species all need to be the same for the results that you find in the study to be the results that you hope to achieve when taking it. For example, with the strain Lactobacillus rhamnosus GG, the genus is Lactobacillus, the species is rhamnosus and the strain is GG. If any one of those are different in your supplement, you may not attain the same results.

With the growing popularity of probiotics, there is a huge variety of supplements from which you can choose. The most important thing is to determine what type of probiotic microorganism you need for your condition. Do not just take the supplement that provides the most kinds of organisms. You need to do your research and be sure that there are scientific studies to support what you take. New research is emerging, so if you don't find what you need right, now keep looking. Your doctor can help you decide if trying probiotics might be helpful for you and can advise you regarding the amount and type of probiotics that may be appropriate in your case.

Where can I get more information on probiotics?

USProbiotics.org (

"Herbs and Supplements," MedlinePlus (

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