when it comes to using antibiotics, both gria and martin believe we need a better balance. - by and large, we have overestimated the value of antibiotics. we're giving antibiotics like water. the big dogma is it might not help you, but it won't hurt. but what if it does hurt? the's more and more evidence we're losing microbial diversity, it's just going down. - [julia] martin and gloria wa to prevt the further loss of diversity in our microbiomes. - we've overdone it. now we have to find a more moderate approach. and ultimately, if we find a more moderate approach, then maybe we can stop the decline in diversity, but how do we get it back? that's gonna require restoration. - [julia] one intriguing candidate for microbial restoration is the h. pylori bacteria, the same one that barry marshall infected himself with. - most doctors in the world are trying to get rid of helicobacter on the idea that it's a bad guy and its. but since then, we've been finding all kinds of good things that e bacteria does. - it turns out that some microbes are double agents and can be both bad and good for the b