Boise gastroenterologist: When it comes to probiotics, know the truth vs. the hype

It’s hard to find someone these days who isn’t taking or least talking about probiotics, so it makes sense to learn a few things about them.

In the world dominated by bad bacteria, probiotics are the good guys — the live microorganisms that, when taken in adequate amounts, offer a health benefit. (While probiotics are found naturally in your body, they are also found in some foods and special supplements.)

Their close allies are prebiotics — the ingredients in your diet that help these good guys grow and flourish. (One example of a prebiotic is inulin, a plant substance.)

Here are some answers to the questions that you may have:

Q: So what are the bare essentials for bacteria to qualify as probiotics?

A: They should be of human origin, can’t be destroyed by stomach acid, are able to attach to the intestinal lining, produce substances that fight off the bad-guy bacteria and decrease the level of inflammation in the intestine, and should be safe for use. (I know. Duh on that last one, right?) Lactobacillus, Bifidobacterium and Saccharomyces are the three most-commonly used and widely studied probiotic species of bacteria.

Q: What can they do for me?

A: Well, quite a bit. Let’s look at some of the proven benefits.

1. Treating infectious diarrhea caused by Clostridium difficile. This is probably the biggest achievement of probiotic therapy. Clostridium difficile is a common cause of severe diarrhea, and it’s caused by an imbalance in the good vs. bad bacteria in the intestine. The imbalance is typically caused by an antibiotic that wipes out the good bacteria. A restored balance by a fecal transplant (yes, you read that right) from a healthy donor breaks the cycle and cures the disease.

2. Irritable bowel syndrome is a common disorder causing patients a variety of symptoms such as diarrhea, bloating, gas, cramps and nausea. Several studies have shown improvement in symptoms, particularly with pain, when patients were given probiotic supplements containing Lactobacillus, Bifidobacterium and Streptococcus.

3. Inflammatory bowel disease is a disorder that causes ulcers and inflammation of the intestine. Some studies have shown that probiotics may be helpful in preventing relapses of the disease.

4. Infections: Studies show that daily supplementation of probiotics in healthy adults can reduce the duration of upper-respiratory tract infections. (Note that no such effect was demonstrated for urinary tract infections.)

Q: What else can’t they do?

A: The marketing engines of the firms manufacturing these products sometimes over-hype the benefits of taking them. It’s important to realize that probiotics are good, but they aren’t silver bullets either.

Here are some common myths about their benefits:

1. Inflammatory bowel disease: These supplements have a modest benefit at best in preventing a relapse of this disease — even when you only have a mild form of the disease. If you are already experiencing symptoms of a flare-up, or the disease is severe, taking probiotics will likely not be enough.

2. Irritable bowel syndrome: Again, the benefits are modest and often only helpful in milder forms of the disease.

3. Food allergies: There is a lot of research on the possible benefits of probiotics, but there is no conclusive evidence to suggest they are helpful.

Q: What’s the best way to take them?

A: There are two main ways to take them: eating probiotic-rich foods or by taking commercially manufactured supplements.

Let’s look at each one.

1. Probiotic-rich foods: Yogurt is the best-known food group rich in probiotics. The FDA requires that any product labeled “yogurt” must have Lactobacillus and Streptococcus.

However, some companies pasteurize or heat the product after adding the bacteria — rendering them essentially useless. That’s why it’s very important to make sure that the label specifies “live cultures,” meaning bacterial cultures are added after pasteurization. Other dairy products rich in probiotics are buttermilk, some cheeses and Kefir (fermented cow’s milk).

Examples of nondairy probiotic-rich foods are sauerkraut (fermented cabbage), miso, pickles and tempeh (a soy product).

It’s also important to consume foods rich in prebiotics — the ingredients that help the probiotic bacteria flourish. Most common in this category are the fiber-rich foods — such as oats, bananas, garlic and onions.

2. Probiotic supplements: Modern manufacturing of probiotic supplements involves large-scale fermentation vessels, where bacteria are grown in specialized mediums.

There are certain things to keep in mind when choosing the supplement for you:

▪ Make sure the product is encapsulated, so it can survive the gastric acid and reach your intestine

▪ The more strains of bacteria, the better. Make sure it contains at least Lactobacillus and Bifidobacterium strains. Also check for prebiotic ingredients such as inulin.

▪ Look for the number of colony forming units (CFU) of bacteria in the supplements — 1 billion to 3 billion CFUs a day is generally a good dose.

▪ When taking antibiotics, it’s best to take probiotics during the antibiotic course as well as for a couple of weeks after that to prevent the imbalance in gut flora that results in antibiotic-associated diarrhea.

Q: When should I not take probiotics?

A: In general, probiotics have a good safety record, but they are live bacteria. They should not be consumed by newborn babies and people who might have a suppressed immune system, such as people with immune deficiencies, untreated or partially treated HIV, organ transplant recipients, and people taking immunosuppressive drugs or chemotherapy.

This story was originally published March 20, 2016 at 11:23 PM with the headline "Boise gastroenterologist: When it comes to probiotics, know the truth vs. the hype."