Probiotics are gaining in public popularity and are not just a health fad, according to Australian researchers. Speaking at the Asia Pacific Digestive Week conference in Adelaide last week Dr. Ross Butler, chief medical scientist at the Centre for Paediatric and Adolescent Gastroenterology at the Women's and Children's Hospital in Adelaide commented that although he believed that research on the health effects of probiotics has been limited the bacteria do appear to promote intestinal health. He and his colleagues recently identified non-invasive tests that could provide a way to assess the effectiveness of probiotics. One is a urine test to check the permeability of the intestine, and the other is a breath test that measures the metabolic activity of bacteria in the intestines. Excess intestinal permeability is common in diarrhea. . One of Butler's colleagues, Emma Southcott, gave healthy adolescents a probiotic (yogurt) for 2 days. Using the urine test, she found that their intestines became less permeable. "We are trying to define the wellness component first before we study disease states," "Butler commented. A second study, presented for the first time at the conference, examined patients with inflammatory bowel disease. There are two conditions categorized as IBD: ulcerative colitis and Crohn's disease, both of which are characterised by severe inflammation of the intestines. The researchers wanted to see if 5 days of consuming a probiotic preparation would change the metabolic activity of bacteria in patients' large intestines and the levels of short-chain fatty acids, which are believed to be beneficial for digestive health, in their faeces. The probiotic was given to 17 healthy people and 11 IBD patients, who all consumed 150 grams of two types of yogurt per day. This was an open trial to look at mechanisms rather than to treat disease, Butler said. The fecal short-chain fatty acid levels in the IBD patients were significantly different from those of the healthy individuals at the outset of the study, but were normalised after the patients took the probiotic, Butler said. "We also showed they altered their breath testing--it was diametrically opposite after the probiotic in the patient group compared with the normals who didn't change at all," he added. "That way we can say that this probiotic in this form got down to the large bowel and did something--and it did it within the lumen (lining) of the large bowel," Butler stated.