Some bacteria are proving to be powerful allies in the fight against disease
Date: 09/02/01 22:15
By KAREN UHLENHUTH - The Kansas City Star
Probiotics...the good-for-you bacteria. Watch for them to proliferate at a store near you.
Microbes have a nasty reputation in this country, conjuring up thoughts of e. coli, salmonella, contaminated hamburgers, flesh-eating bugs. All manner of products, from cleaning solutions to children's toys, are infused with compounds that promise to obliterate every bacterium from our lives.
But a growing body of evidence suggests that certain bacteria and other living organisms could play a role in fighting disease and boosting health.
While probiotics -- "live active cultures!" -- mostly have been confined to yogurts, acidophilus milk and dietary supplements in this country, Europeans and Japanese gladly gobble them in cheese, juices, candy and other foods.
In the United States "there's a big communications hump to get over for people to see that these things are good for them," said Mary Ellen Sanders, a Colorado-based consultant who specializes in probiotics.
As medical research points to tantalizing new possibilities, American food manufacturers are investigating ways to bring them to market, Sanders said. Two yogurt-makers are rolling out products with higher levels of probiotics and/or prebiotics, a group of compounds that serve as food for probiotic bacteria in the gut where they hang out.
Two years ago Dannon began selling Actimel, a drinkable, dairy-based probiotic supplement, in Colorado. Actimel has been sold in Europe since 1994. It has been well-received in Colorado and eventually will be sold more widely, said Anna Moses, a Dannon spokeswoman.
Stonyfield Farm last year added a prebiotic known as inulin to some of its yogurts, according to Deirdre Fitzgerald, a company spokeswoman. Inulin is a dietary fiber that promotes the growth of helpful gut bacteria.
Stonyfield Farm products are available at several local grocery chains including Wild Oats, Hen House and Hy-Vee stores. Inulin is in O'Soy and YoSelf and Stonyfield's fruit blends. In the next year or two it should be added to all of the company's products, Fitzgerald said.
In addition, a probiotic-laced buttermilk drink from Japan called Yakult is expected to arrive in the U.S. market sometime this year. In Europe and Japan more than 24 million people consume it daily, said Gregor Reid, a professor of microbiology at the University of Western Ontario in London, Ontario.
Other food manufacturers are looking for ways to add pre- and probiotics to their foods -- non-diary products in particular, Sanders said. Because they're not alive, prebiotics can be baked and cooked, she noted.
The greatest challenge in marketing probiotics "is educating people that you need good bacteria," Fitzgerald said. "People think all bacteria is bad."
Although there's been plenty of misinformation through the years about the powers of probiotics, scientific data giving credence to them has mounted steadily.
"It's a whole new science," said Jon Vanderhoof, chief of pediatric gastroenterology at the University of Nebraska Medical Center in Omaha. Clinical studies have firmly demonstrated certain health effects of probiotics -- and left tantalizing clues of further benefits.
Vanderhoof has studied the use of Lactobacillus gg, a probiotic, to treat children with diarrhea resulting from antibiotic use. Lactobacillus gg clearly reduces the severity and duration of such diarrhea, said Vanderhoof, who also advises ConAgra Foods Inc. on functional foods.
"If you have a child who's prone to get diarrhea on antibiotics, you ought to consider this as a means of preventing it," he said.
Lactobacillus gg is not widely available here yet, although it's in Culturelle, a supplement made by ConAgra.
Probiotics also repeatedly have proven to reduce symptoms of people who are lactose-intolerant. There is less evidence for, but lots of interest in, the possibility that probiotics could calm various inflammations of the gastrointestinal tract, such as Crohn's disease, according to Gary Elmer, a professor of medicinal chemistry at the University of Washington.
Probiotics also may effectively treat vaginal and urinary tract infections, Elmer noted, if initial research bears out.
Probiotics appear to operate in several ways, Elmer said. By attaching themselves to the lining of the gut, they can elbow out troublesome bacteria.
Some scientists suspect that certain probiotics may discourage tumors, particularly cancerous growths in the colon, either by emitting protective chemicals or by inhibiting production of compounds that nurture cancers, Vanderhoof said.
Research also has yielded provocative clues that particular bacteria and other organisms may help to reduce the level of blood cholesterol, and may rein in overactive immune systems that can cause asthma, allergies and eczema, for example.
Many medical researchers suspect that the epidemics of asthma, Crohn's disease and other immune disorders may indicate we've become too clean for our own good. The "hygiene theory" surmises that immune systems learn to function in the presence of benign intestinal organisms. But as human communities have "cleaned up," reducing exposure to such organisms, immune systems have gone amok.
Joel Weinstock, who directs the Center for Digestive Disease at the University of Iowa Medical School in Iowa City, tested the premise that the immune system could be redirected by feeding a dose of the eggs of a harmless intestinal worm, common in pigs, to six people with Crohn's disease. Within a few weeks, five of the six were symptom free. After two more doses, the sixth subject was also.
Weinstock is now testing his theory on a larger number of subjects. Similar research in under way with subjects who have multiple sclerosis.
Scientists trying to understand the role of certain microbes in maintaining health point to a recent study in Finland as particularly intriguing. Researchers fed Lactobacillus gg to a group of pregnant women with a history of atopic eczema, asthma or allergic rhinitis in either their immediate families or their partners. Then they fed it to the infants until they reached 6 months of age.
When the children turned 2, researchers evaluated them for recurrent atopic eczema, considered the best predictor of allergy and asthma and other similar diseases later life. They found it twice as often in a control group of children who had not received the probiotic as in the group that had.
Vanderhoof considers these some of the most significant findings on probiotics. The study suggests that probiotics may teach a developing immune system to target harmful bacteria and viruses, "rather than developing what we'd call an allergic response," he said.
Probiotics have been largely overlooked by the federal government and by pharmaceutical companies, who do not stand to make much profit from them, according to a couple of researchers. However, Reid, the Canadian microbiologist, is hopeful that probiotics may be on the verge of winning over more support and interest in the United States, as has been the case in Europe and Japan for decades.
"The argument that `The science isn't there' doesn't stick anymore," he said. "People are saying, `Maybe there is something real to this.' "
To reach Karen Uhlenhuth, features reporter, call (816) 234-4783 or send e-mail to firstname.lastname@example.org.
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