The more squeamish among us may prefer to ignore their unwitting role as landlord to this invisible community. But do so at your own risk! These friendly bacteria have important roles in metabolizing our food, producing vitamins, and protecting us from infectious overgrowth of harmful yeast and disease-causing bacteria. Beyond these established roles, there is a growing body of research investigating associations between the health of one's gut flora and the health of one's body.
Although the implications of this emerging research remain controversial, it has been noted that people with normal digestive function tend to have a different profile of gut flora than people with Irritable Bowel Syndrome (IBS), and obese people may have gut flora skewed toward different classes of bacteria than those at a normal weight. It has also been observed that infants given antibiotics in their first six months of life have a greater risk of obesity later in childhood, and those given antibiotics in their first year may have an increased risk of asthma. While these associations most certainly do not imply causation, there does seem to be growing consensus in the research community that our gut flora play a role in health that is far wider-reaching than once presumed. [Read more: Tending Your Inner Ecosystem]
Angela Haupt is a health reporter for U.S. News & World Report. You can follow her on Twitter or reach her at email@example.com.