Yogurt for an Upset Stomach? If It Has Probiotics

By:
Karen Pallarito

If you suffer from peptic ulcers or other gastrointestinal (GI) problems, you might instinctively head for the medicine cabinet. But you might be better off reaching for the refrigerator and searching for a food that contains probiotics. Although more research is needed, some studies suggest that consuming yogurt or lactic-acid producing bacteria may be beneficial for a whole range of GI troubles.

Yogurt is one of the best-known sources of "probiotics," a term that describes foods and supplements containing microorganisms that are beneficial to the GI tract. Probiotics are sometimes called "friendly" bacteria because they help to replenish good microorganisms and inhibit the growth of harmful ones.

Other probiotic sources include kefir, a fermented milk product; acidophilus milk; fermented foods like tempeh, miso and kim chi; and nutritional supplements.

"People have been talking about probiotics for years and years and years," observes dietitian Pat Baird, a nutritional consultant and columnist. "What's happening is that in the last five years or so, people had become more interested, I believe, in taking charge of their health and looking at other ways through food that they can maintain better health and longevity."

In a 2004 review article titled "Yogurt and Gut Function," which appeared in the American Journal of Clinical Nutrition, researchers said the list of health problems that respond to these good bacteria includes diarrhea, constipation, inflammatory bowel disease, lactose intolerance and Helicobacter pylori, a type of bacteria responsible for a majority of peptic ulcers.

More recently, a double-blind study reported in the journal Environmental Health found that employees who received a daily dose of probiotics missed work less frequently due to respiratory and GI problems than those who received a placebo. In the study group, sick days caused by these health problems could be reduced by 55 percent compared with the placebo group, the Swedish authors noted.

But probiotics aren't just for people with symptoms, adds Baird, who has been a consultant the Dannon Company Inc., a national yogurt producer, headquartered in White Plains, NY.

Depending on the type of bacteria you are consuming, probiotics can help maintain normal GI function, she says. Or they can replace good bacteria wiped out when people take powerful broad-spectrum antibiotics. "Personally," she says, "I think everyone should have some kind of probiotic every day."

Despite clinical evidence suggesting that probiotics have beneficial effects, microbiologists still struggle to understand the underlying science.

"We know that probiotics work with respect to certain GI disorders, such as traveler's diarrhea," says Kathene C. Johnson-Henry, a laboratory manager in the Division of Gastroenterology, Hepatology and Nutrition at The Hospital for Sick Children in Toronto, Canada. "But in terms of the basic science and the reasons behind why they work or how they work, this is what we're trying to establish."

Johnson-Henry and her colleagues recently showed that pretreating rats with probiotics before exposing them to a stressful situation eased gut problems. The study, which appeared in the journal Gut, was designed to elicit some of the same GI-related effects of stress seen in humans, specifically irritable bowel syndrome.

But, she adds, it's too soon to know what the results might imply for humans. More research is needed, for example, to determine the amount of probiotic needed to elicit a positive health effect in people and the duration of the benefit.

Another variable is the type of bacteria used. In the rat study, for example, researchers used Lactobacillus acidophilus and Lactobacillus rhamnosus.

But different species of bacteria have different effects on different cells or within different organs of an animal, Johnson-Henry explains. "That's why with a lot of the research that's going on now," she says, "we tend to isolate or use one or two bacteria at a time and try to determine what effects those bacteria have."

So what can consumers do to make sense of it all? "They have to read the label." Baird says. That's the best way to know what various probiotic products may contain as well as their nutritional content.

For more information on probiotics

Wikipedia, the online encyclopedia, has a good definition on how probiotics affect the body.

Sources: Pat Baird, MA, RD, FADA, nutritional consultant, columnist and author of the book Be Good to Your Gut: Recipes and Tips for People With Digestive Problems, Greenwich, CT; Kathene C. Johnson-Henry, BSc, laboratory manager, Division of Gastroenterology, Hepatology and Nutrition, The Hospital for Sick Children, Toronto, Canada; Cancer Nutrition Info, LLC, Atlanta, GA; August 2004, American Journal of Clinical Nutrition; November 2005, Environmental Health: A Global Access Science Source; March 2006, Gut