Probiotics, or friendly bacteria, can help fight digestive tract problems

• Bacteria in your food are a bad thing, usually: Think of E. coli or other harmful bugs.
• But there's a whole other world of "friendly" bacteria.
• Called "probiotics" and found in yogurt, among other foods, they provide health benefits beyond the regular live cultures found in those foods.
• Probiotics are among the fastest-growing category of functional foods, according to the market research firm Mintel, which cites a 140 percent increase last year in the launch of new probiotic-fortified products.
• So far, the strongest evidence on probiotics has focused on digestive-tract problems such as lactose intolerance and diarrhea -- including infectious diarrhea among children and the type that develops after a person has taken antibiotics (which wipe out both good and bad bacteria, altering the natural balance of the digestive tract).
• Europeans have long embraced the concept of probiotics (which is derived from the Greek, meaning "for life"), but Americans haven't fully warmed up to the idea of downing a drink swimming with billions of live microorganisms.
• "We've done a good job in this country of scaring people to death of microbes," said Mary Ellen Sanders, president of the International Scientific Association for Probiotics and Prebiotics, a non-profit scientific organization.
• Some of the most exciting research on probiotics involves the potential to boost immunity, said Allan Walker, a professor of nutrition and pediatrics at Harvard Medical School.
• Probiotics appear to communicate with the cells in our intestines to turn on antibodies to fight infections, Walker said.
• This "cross-talk" helps rev up our immune response so we're better prepared to deal with invading bacteria and viruses that could make us sick, he said.
• · A seven-month study of more than 570 children in day-care centers found that intake of a probiotic milk reduced the number and severity of respiratory infections and the need for antibiotics.
• If you want a yogurt with probiotics, check the label.