0:00:04.662,0:00:06.465 The next time you look in the mirror. 0:00:06.465,0:00:07.585 think about this. 0:00:07.585,0:00:08.432 In many ways, 0:00:08.432,0:00:10.661 you're more microbe than human. 0:00:10.661,0:00:12.283 There are ten times more cells 0:00:12.283,0:00:13.753 from microorganisms - 0:00:13.753,0:00:15.483 bacteria, viruses, fungi- 0:00:15.483,0:00:18.651 than human cells in and on our bodies. 0:00:18.991,0:00:20.391 And our genes are outnumbered 0:00:20.391,0:00:23.742 a hundred to one by microbial genes. 0:00:23.742,0:00:25.214 Scientists even have a name 0:00:25.214,0:00:27.243 for all these microbial genes: 0:00:27.243,0:00:29.386 the human microbiome. 0:00:30.484,0:00:32.323 Now, this might make a lot of people 0:00:32.323,0:00:34.355 rush for the hand sanitizer, 0:00:34.355,0:00:36.035 but it turns out most 0:00:36.035,0:00:38.172 of these microorganisms aren't bad, 0:00:38.172,0:00:40.124 germs that will make us sick, 0:00:40.124,0:00:41.702 most are good. 0:00:41.702,0:00:43.410 And without these good microbes 0:00:43.410,0:00:45.405 our bodies don't seem to do as well. 0:00:45.405,0:00:47.272 We don't seem to be as healthy, 0:00:47.272,0:00:49.166 and we actually might get sick 0:00:49.166,0:00:50.165 more often. 0:00:52.205,0:00:53.272 So one question is: 0:00:53.272,0:00:54.621 where do our microbiomes 0:00:54.621,0:00:56.564 come from in the first place? 0:00:56.564,0:00:57.894 Well, like a lot of things, 0:00:57.894,0:00:59.425 it starts with our mothers. 0:00:59.710,0:01:02.031 As the infant passes [br]through the birth cannal, 0:01:02.031,0:01:04.970 it gets coded with microbes from the mom. 0:01:04.970,0:01:06.822 These microbes may kind of 0:01:06.822,0:01:08.705 seed the baby with just the right mix. 0:01:09.315,0:01:11.205 Combined with bacteria in breast milk 0:01:11.205,0:01:13.405 and other microbes we encounter early on, 0:01:13.405,0:01:15.551 they seem to slowly take shape 0:01:15.551,0:01:18.082 in our first few years of life. 0:01:19.223,0:01:20.933 The overall mix of our microbes 0:01:20.933,0:01:22.693 becomes very personal, 0:01:22.693,0:01:25.674 sort of like a fingerprint, [br]or maybe a blood type. 0:01:25.674,0:01:27.346 But our microbes tend to resemble 0:01:27.346,0:01:29.331 those of our parents and siblings. 0:01:29.331,0:01:32.552 And may stay with us [br]for much of our lives. 0:01:35.714,0:01:38.173 They may also be doing [br]all sorts of things, 0:01:38.173,0:01:40.993 such as educating our immune cells, 0:01:40.993,0:01:41.970 like this one. 0:01:41.970,0:01:43.352 Teaching them the difference 0:01:43.352,0:01:45.232 between things they should fight off 0:01:45.232,0:01:46.903 –bad bugs that might make us sick- 0:01:46.903,0:01:48.704 And things that aren't a threat, 0:01:48.704,0:01:50.603 like our good microbes. 0:01:54.176,0:01:55.455 When we are adults, 0:01:55.455,0:01:57.730 microbes become our first line of defense, 0:01:57.730,0:01:59.700 fighting off germs that try to invade our 0:01:59.700,0:02:01.084 bodies, protecting their 0:02:01.084,0:02:03.012 turf, while protecting our health. 0:02:05.591,0:02:07.325 Scientists have discovered they can 0:02:07.325,0:02:09.752 even spew out their own antibiotics. 0:02:16.172,0:02:18.055 The types of microbes in your body 0:02:18.055,0:02:20.443 vary depending exactly where they live, 0:02:20.443,0:02:23.055 like different ecosystems in nature. 0:02:23.900,0:02:28.192 There are wet places, like[br]our mouths, noses and armpits. 0:02:28.192,0:02:31.014 Oily places, like our scalps and backs. 0:02:31.014,0:02:33.604 And dry places, like our forearms. 0:02:33.604,0:02:35.211 Different species of microbes 0:02:35.211,0:02:38.306 have adapted to each of these habitats. 0:02:40.503,0:02:43.181 The biggest, most important [br]microbial habitat 0:02:43.181,0:02:45.533 seems to be in the gut. 0:02:45.533,0:02:47.855 It's the most complex, the most diverse, 0:02:47.855,0:02:49.732 and everything microbes are doing 0:02:49.732,0:02:51.552 everywhere else in our bodies: 0:02:51.552,0:02:52.854 fighting off infections, 0:02:52.854,0:02:55.856 revving up and dampening down [br]our immune systems, 0:02:55.856,0:02:57.284 signaling cells... 0:02:57.284,0:03:00.083 That's all happening [br]in the gut in spades. 0:03:00.083,0:03:03.782 They even seem to help [br]regulate our metabolisms. 0:03:03.782,0:03:05.344 How much energy we burn, 0:03:05.344,0:03:07.165 and how much fat we store. 0:03:07.303,0:03:09.852 So, if it's not functioning properly [br]for some reason 0:03:09.852,0:03:12.686 because of what we eat, [br]antibiotics we take, 0:03:12.686,0:03:15.945 that may actually lead [br]to all kinds of diseases. 0:03:15.945,0:03:18.521 Diseases like colon cancer, colitis, 0:03:18.521,0:03:21.550 maybe even diabetes[br]and obesity. 0:03:24.954,0:03:26.583 Some scientists think one reason 0:03:26.583,0:03:28.282 a lot of diseases are increasing 0:03:28.282,0:03:31.394 is because we've lost key gut microbes. 0:03:31.394,0:03:34.694 Our microbiomes look far [br]less diverse compared to those 0:03:34.694,0:03:36.034 compared to those of people 0:03:36.034,0:03:38.794 in less developed countries [br]and earlier generations. 0:03:38.794,0:03:40.124 And remember how we get 0:03:40.124,0:03:41.882 our microbiomes in the first place? 0:03:41.882,0:03:43.683 From our mothers when we are born, 0:03:43.683,0:03:45.060 and from breast milk? 0:03:45.060,0:03:46.821 Well, some scientists think that 0:03:46.821,0:03:48.914 too many babies aren't getting that, 0:03:48.914,0:03:50.475 because of all the C-sections, 0:03:50.475,0:03:52.297 and not enough breast feeding, 0:03:52.297,0:03:55.112 plus all the antibiotics [br]kids get these days, 0:03:55.112,0:03:58.055 and our obsession with cleanliness. 0:03:58.055,0:03:59.994 All this may help explain why problems 0:03:59.994,0:04:02.315 like asthma and allergies,[br]have been soaring 0:04:02.315,0:04:04.784 Maybe because our microbiomes 0:04:04.784,0:04:06.314 never taught our immune systems 0:04:06.314,0:04:08.694 how to work the right way. 0:04:12.245,0:04:14.216 Maybe swallowing good microbes probiotics 0:04:15.213,0:04:17.473 could prevent and treat some diseases. 0:04:17.745,0:04:19.682 So could taking prebiotics 0:04:19.682,0:04:22.033 essentially food that good microbes love. 0:04:29.083,0:04:30.951 We end our story with a reminder. 0:04:30.951,0:04:32.984 This research is really new, 0:04:32.984,0:04:34.541 we still have a lot to learn 0:04:34.541,0:04:36.101 about what many of our microbes 0:04:36.101,0:04:37.355 are really doing. 0:04:37.355,0:04:38.563 But scientists say that 0:04:38.563,0:04:40.471 it's getting clearer and clearer that 0:04:40.471,0:04:43.504 the tiny organisms all over our bodies 0:04:43.504,0:04:47.143 are essential to our health and happiness.