Your gut bacteria could be changing how many calories you absorb

The calorie count printed on a food package might seem like a straightforward measure of how much energy you will get from eating it. But the number on the label does not necessarily match the calories your body actually absorbs. One reason is that digestion involves more than just breaking down food. It also depends on trillions of microorganisms living inside your digestive system.

Researchers at Arizona State University have developed a mathematical model that explores this often overlooked part of digestion. Known as DAMM, short for digestion, absorption and microbial metabolism, the model tracks how food moves through the digestive tract, how much energy the body absorbs directly, and how gut microbes process whatever remains. It also estimates which products of digestion are absorbed and which leave the body as waste.