Okay, so maybe it isn’t a headline you expect to see very often, but lately things are changing, and I say they’re definitely changing for the better. More and more people are becoming aware of the vast numbers of microscopic bacteria living inside their bodies, and a whole new field of science has emerged to study the literally trillions of microorganisms that grow and thrive inside us—helping us do everything from digesting our food to boosting our immune defenses and protecting us against illness and disease.

To help you get an idea of just how important these bacteria are, consider this: In the human body there are 10 times more microbial cells than human cells. Just think about that for a second—it means that roughly 90% of our genetic makeup is microbial. Whoa! I don’t know about you, but I think it’s pretty amazing that something we can’t even see can be such an important part of who we are.

In the gut especially, there are about 100 trillion bacterial cells. Some are good, some are bad, and some are neutral, but the key is making sure you always have more good than bad (somewhere around 80% to 20%), because the good guys—called probiotics—help to nourish and protect not just your digestive tract, but your whole body.

In just the last few years scientists have made some pretty amazing discoveries about the role of probiotics in human health, and studies show that taking a daily probiotic supplement can help with digestive conditions such as irritable bowel, diarrhea and constipation, as well as aid in vitamin production, weight loss, mental health, and of course building up our immune defenses by crowding out harmful, disease-causing bacteria.

So the next time you hear someone talk about bacteria, resist the urge to cringe and remember the good guys! Probiotics literally means “for life,” and no wonder. I heard this great quote the other day by Dr. Jeffrey Gordon at the Center for Genome Sciences at Washington University, and it really sums it up: “Most people have this view of our encounters with microbes from the perspective of disease. But that couldn’t be farther from the truth. Most of our interactions with microbes are beneficial and are healthy.” Like I said, hooray for bacteria!