The difference in our microbiomes, just to put into context, because, you know, five years ago, you'd probably be talking to someone about how the genetic revolution is going to give us genetic testing to tell you what to eat right it turns out that you know we share 99.5 percent of our dna with each other you and i are fifth cousins on average right oh lovely well i'd expect a christmas card and you can send me some cake yeah so um but we only share less than 20 25 percent of our gut microbes so most of our microbes are completely unique to us and so it's that and this is why our response to food is so different and even in identical twins who have 100% of the same genes so it starts to make sense only in the context of having discovered the gut microbiome you can see why people got it wrong before they didn't really think there was anything else that should you know theoretically we should all behave the same in this old-fashioned idea that you know our gut is like this tube and our metabolism is like a furnace you put calories in one end you burn it the other end and that's all that matters