Scientists have identified a key microbe in our guts that helps us glean more calories from food. The discovery backs the idea that the type of microbes in our gut help to determine how much weight we gain, and that seeding the intestine with particular bugs could help fight obesity.
Samuel Buck of Washington University in St Louis, Missouri, and his colleagues focused on one microbe called Methanobrevibacter smithii, which is effectively a waste-removal bug. “It’s a minor component of the gut flora with a major impact,” Buck says tactfully.
M. smithii may have a dirty job, but Buck and his colleagues have now shown that it is a vital one. They found that by clearing waste products it helps other gut bacteria digest some of the fibrous components of food that we cannot, and turn them into material that our bodies can use. Without these bugs, waste accumulates and blocks the activity of other gut bacteria.
The researchers found that mice with a hefty dose of M. smithii in their guts are fatter than those that don’t have the bacteria.
More details on the findings can be found at the link. The manuscript is forthcoming in PNAS, so I can’t comment much on the methodology, but it’s certainly another intriguing bit of evidence that suggests diet plus exercise isn’t all there is to it, as far as establishment and maintenance of our weight.