We share our bodies with trillions of microbes that are critical to staying healthy, but now scientists are getting a much-needed close look at how those bugs can spur disease.
A single test to see what gut bacteria you harbour would not tell much. Research published on Wednesday found that repeat testing spotted the microbial zoo changing in ways that eventually may help doctors determine who’s at risk of preterm birth, inflammatory bowel disease, even diabetes.
At issue is what’s called the microbiome, the community of bacteria, viruses and fungi that live on the skin or in the gut, nose or reproductive tract.
“The instability of our microbiome might be an early indicator of something going awry,” said Dr. Lita Proctor, at the National Institutes of Health.
A hot field
Microbiomes start forming at birth and are different depending on whether babies were born vaginally or via C-section. And they change with age and different exposures, such as a course of antibiotics that can wipe out friendly bacteria along with infection-causing ones.
For a year, a Harvard-led team tracked 132 people with conditions such as Crohn’s disease and some healthy people for comparison. As the diseases wax and wane, so does microbial activity, researchers reported in the journal Nature . Surprisingly, many times a patient’s gut microbiome changed radically in just a few weeks before a flare-up.
Some of the microbes produce molecules that keep the intestinal lining healthy, likely one reason the disease worsened when those bugs disappeared, Proctor said.
Also in Nature , a Stanford University-led team tracked 106 people for four years, some healthy and some pre-diabetic. Up to 10% of pre-diabetics will develop diabetes each year, but there’s little way to predict who.
The researchers did quarterly tests for microbial, genetic and molecular changes, plus testing when the volunteers caught a respiratory infection and even while some deliberately put on and lost weight. Not surprisingly, they found a list of microbial and inflammatory early warning signs of brewing diabetes.
But most interestingly, people who are insulin-resistant showed delayed immune responses to respiratory infections, correlating with tamped-down microbial reactions.
