Boston—The human gastrointestinal tract harbors 10 times more bacterial cells than there are cells in the entire human body. These intestinal microflora can benefit health by breaking down toxins, synthesizing vitamins, and defending against infection. But they also play a role in such diseases as peptic ulcers,
diarrhea, colorectal cancer, and inflammatory bowel disease.
A great deal remains unknown about this collection of microbes in our “microbiome,” according to molecular microbiologist Colin Hill, PhD, of University College in Cork, in Ireland. “Each person has an individual fingerprint of bacteria of between 500 and 1000 different species that is established early in life,” he said. “While each person's microbiome is thought to remain relatively stable throughout life, many of the bacteria can't be cultured and are difficult to study.”
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