 All right, and that's true of social interactions as well. OK, so, and like I said, television entrains our daytime rhythms. And that can explain a paradox. So every time they do studies of television viewing, they find that it's terrible for your health. One Australian study found that for every hour of television viewing, you lose 22 minutes off your life. Plus, you have to watch 12 minutes of commercials. So, you know, basically it's a really bad idea to watch TV. But it's funny. You know, you would think if looking at a screen was such a problem, then all these people who get jobs where they're looking at computers all day would have terrible health. But you look at them and know there's no negative health effect to having an office job where you look at a computer all the time. All right, so what's going on? It's that the TV viewing is happening at night. It's disrupting their circadian rhythms. Whatever happens at the office in the day is not disrupting circadian rhythms. All right, so in the evening, what do you want? You want companionship, all right? You want loving support. And like I said, with a lot of these things, even if you can't get the really authentic loving mate, you can often find substitutes. A good substitute is a dog. So it turns out here's a heart disease study of people who had had a heart attack, and they looked at the likelihood of having another heart attack and dying. And of the dog owners, there were 87 dog owners. Only one died in like the five or six year follow up. But of the 282 people who didn't have a dog, 19 died. All right, so that's more than a six-fold higher risk for the non-dog owners. So having some kind of companionship loving support is really crucial. Very important to create a pro-sleep environment. As Shakespeare said, sleep is a nourisher of our health. We need it. Disrupted sleep increases mortality by 90%. And for good sleep, it's really important that you control your environment. Create a quiet environment, a dark environment. Have a regular bedtime. Go to bed early enough so that you can wake to a natural waking. Don't wake with alarms. And like I said, all of these circadian rhythm training effects, their influence extends for 36 to 48 hours. So everything that you've done in the previous 48 hours will affect your sleep. And the better you've entrained your circadian rhythms in the previous 48 hours, the better your sleep will be that night. So tend to all those other things like social interactions, like exercise, like meal timing. And particularly if you have sleep problems, you need to fix those. All right, so summary, what's the best strategy? Get bright, natural light in the day. Arrange your environment so that you get orange, red lights at night. And I recommend having two sets of lighting in your home. Nighttime lights, daytime lights. And define your own 12-hour day. So in our home, we use 8 AM to 8 PM. And at 8 AM, I go around our home. Open all the drapes, get as much sun as I can. Turn on all of our bright, natural 5,500, 6,000 Kelvin color temperature lighting. Make the environment light as bright as I can. At 8 PM, I go around, close all the drapes, turn off all the white lights, turn on orange lights. And then we're lit like a campfire. Get daily exercise, very important. Intermittent fasting, have an extended overnight fast. Do your eating only in the daytime. Try to get most of your calories between noon and 4. So make that your biggest meal. Now most people will have to do cooking in the evening. So get used to having leftovers. So do all of your cooking in the evening, but don't eat immediately after cooking. Save it. Eat it the next day when it's going to be healthier for you. Make sure you're exposed to warmer temperatures in the day, cooler temperatures at night. Make sure you get social interactions in the daytime. Have a calm, loving environment. All of your stress. Schedule it. If you have to have a fight with your spouse, agree to have it the next day in the daytime. Don't do it at night. And make sure you have a regular sleep schedule where you can get plenty of sleep. All right. Third driver of health, germs, bacteria, other things. Now this is really crucial for health. And how do we know this? Well, we can look back at history. And going back to about 1880, life expectancy in 1880 in the US was under 40 years. Nowadays, it's about 80 years. So we've doubled our life expectancy. And how did we do that? Well, here's the rates of mortality from all these diseases. And we only have data going back to 1900. But that blue line that's falling, that was infectious disease mortality. None of the other lines have gone down. Now, one of them is heading down now, cardiovascular disease. And why is that? Well, heart attacks are caused by infections. All right, so all of these serious infections, they used to kill mostly infants who have suppressed immunity. And they killed a lot of young people. When people survived childhood infections, they'd still maintain all those infections in their body. And those infections would gradually build up and eventually give them a heart attack 50, 60 years later. And so this line is really the echo of this line. These are the people who survived these. And once you got to the point where no one was having them, then the heart disease rate is going to go down to zero, similar to this. It's projected to reach down to this level about 2020, which is about one human lifetime after the time we got rid of these infectious diseases. Now, what got rid of them? It's really hygiene. There were two big things that did it. One of them was the invention of things like flush toilets, indoor plumbing, sewage treatment, piped water coming to everyone. So we'd all get clean water. And when we had diarrhea, we'd go to the toilet and we'd flush it down and it would all get treated. So the germs would no longer spread from one person to another. And that was a huge improvement. And if you know the timeline, when did Thomas Crapper invent the flush toilet? That was around, like, 1870. When did we complete the build out of sewage treatment and sewage lines in the United States? It was in the 1930s, 1940s. So that whole process was going on between about 1870, 1940. And that coincided with this drop. And then the other big factor, the invention of the automobile. So Thomas Edison's Scourge of Humanity by Henry Ford, great benefactor. So what happened? We used to have all these horses going around all of our towns and cities. And the horses would leave horse manure all over the place. And people would have to go collect it and they'd pile it up in New York City. They were generating something like a million tons of horse manure per day, just from in the year 1900. They'd pile them up on street corners and eventually they'd be ferried out to the country for use as manure. But what do you have when you have all this manure around on the streets? You've got lots of flies. And the flies go sit on the manure and then they go around and they sit on food and everything else. And they're spreading germs all over the place. And so when we replaced all the horses with the automobiles, and by about 1940, everybody has an automobile. So we got rid of a lot of germs. And there were a few other things like the invention of vaccines. Antibiotics didn't come around until the 1940s. So penicillin, the first antibiotic, I think it was discovered around 1938 but wasn't available until after World War II. That was really after. And the only thing it really helped with was syphilis among the major causes of death. All right, now it's important to realize although we brought infectious disease mortality low, we haven't eliminated infections. And everybody carries chronic infections, everybody gets them. All right, so here's just one study. They looked at five common infections. They looked at who's got antibodies against these infections. The prevalence was 94% have antibodies to cytomegalovirus. 90% have antibodies to herpes-symblex virus one. That gives you cold sores in the mouth if you don't brush your teeth for a long time. 38% have herpes-symblex virus two, 80% H. pylori, 42% comitophile anemone. And here's a plot, well over 70% of people had at least three of the five. Okay, so everybody gets these infections. They have significant health effects. It's almost impossible to get diabetes if you're not infected with cytomegalovirus. All right, but unfortunately, almost everybody is. So, all right, but all of these things sabotage our health. As we go through life, we acquire more of them. So here's a rate of acquisition. C. pneumoniae, if you're 20 years old, 27% chance you're infected by 40, 34% chance by 50, 53% chance by 75, 65% chance. And similarly with herpes-symblex virus two, 16%, 24%, 46%, 56%, 63%. Every year of your life, you have some chance of getting exposed to these things. Once they're in your body, they're there to stay. They gradually multiply over the course of your life. The burden becomes greater and greater and they cause more and more health problems for you as you get older. All right, now it turns out there's a geographic distribution of germs where you're most likely to be exposed to germs. Tends to be in the US, the South has the highest infection rates. And if you look at diseases, disease rates, they track the infection rates. So this particular one was chlamydia, but others are similar. Generally speaking, places with high infection risk, they tend to be wet, wooded, warm. They have a lot of ticks and mosquitoes. Alaska has high rate of infections. That's probably because they don't entrain circadian rhythms well. They don't get a lot of sunlight. They don't make vitamin D. All right, so here's diabetes prevalence. Here's stroke prevalence. Here's obesity prevalence. Where is a good place to live if you don't want to be exposed to microbes? The Rocky Mountains, really good location. They don't really have mosquitoes. They don't have ticks. When you go to high elevation, you're pretty well protected. Some keys to hygiene. Cook things in water. And so if you're simmering, boiling, you're gonna kill all the germs. Food is a major vector for germ transmission. If you think of what are we putting into our bodies every day or putting in three or four pounds of food, you can easily, some germs can hijack or take stow away and take trips along with that. And it's really good to kill them before you eat them. How did the recent Ebola epidemic start? It's thought that the reservoir of Ebola in Africa is the bat population. And bat stew is a pretty popular food. In Africa. So maybe the way it got started, somebody ate an undercooked bat. They hadn't simmered their bat long enough and they picked up an Ebola infection. And there's others. So pork tends to be a good source of infections. A lot of people get hepatitis infections from eating pig liver. You wanna cook things well. It's important to wash your hands. So again, hygiene, like I said. Automobiles, plumbing, and hand washing helps. Marriwell, sexually transmitted disease are a very common source of infections and burden. Avoid mosquitoes and ticks. So that's another major vector for infectious disease transmission. All right, now there's another aspect to these microbes. They're not all bad.