Many people still regard bacteria and other microbes just as disease-causing germs. But it’s a lot more complicated than that. In fact, it’s become increasingly clear that the healthy human body is teeming with microorganisms, many of which play essential roles in our metabolism, our immune response, and even our mental health. We are not just an organism, we are a “superorganism” made up of human cells and microbial cells—and the microbes outnumber us! Fueling this new understanding is NIH’s Human Microbiome Project (HMP), a quest begun a decade ago to explore the microbial makeup of healthy Americans.
About 5 years ago, HMP researchers released their first round of data that provided a look at the microbes present in the mouth, gut, nose, and several other parts of the body . Now, their second wave of data, just published in the journal Nature, has tripled this treasure trove of information, promising to further expand our understanding of the human microbiome and its role in health and disease . For example, the new DNA data offer clues as to the functional roles those microbes play and how those can vary over time in different parts of the human body and from one person to the next.