Could you grow better gut flora?

Chris - Kevin, it's very interesting you raised this because we're just at the stage now where we can begin to answer these sorts of questions which are really important, but it dawned on people about 10 years ago that when we look at the human genome, we're ignoring at our peril something which is orders of magnitude more complicated which our metagenome. In other words, the genetic contribution made to our health and well-being by the millions and millions of bacteria that live on us and in us. They're all lending us their genetic know-how and they contribute to our health, every bit as much as our own DNA does. When we take antimicrobial agents like the antibiotics you took for Streptococcal throat infection, then this does wipe out many populations of those microbes that naturally live in your intestines and it upsets the balance. What the consequences of that are, varies from person to person. What the long term consequences are, at this stage, we don't really know. But now, scientists are in a position to answer those sorts of questions because we have very powerful DNA technology today that we didn't have 10, 20 years ago. It's now perfectly possible to take samples from individuals, before, during and after antibiotic therapy which is what scientists have now been doing to read the genetic sequences in there and work out what the genetic fingerprint of the microorganisms that live in someone's intestines and on their skin are. And then to see what impact taking antibiotics has on those microbial populations. The evidence is that it makes a very big difference and there's some evidence that it makes an indefinite difference. In other words, once you've taken antimicrobial agents, then some bacteria disappear for good from your intestines and that may have a health consequence. For instance, there are microbes that get lost which breakdown a chemical called oxalic acid. Oxalic acid contributes to kidney stones and it's interesting that people tend to get kidney stones once they reach middle age. And by middle age, they've also had a certain number of doses of antibiotic drugs which makes them much more likely therefore to have wiped out that particular population of bugs. So, it might be that in the future, what we do is either build better antibiotics that are kinder to our native intestinal bugs and leave them alone while treating bad bugs or it sounds rather unpleasant, but what we may end up doing is basically banking samples of what lives inside us. And then periodically feeding them back to ourselves to keep our gut microflora in tiptop condition because we know that that's really critical to be healthy