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MLA Full: "Obesity." YouTube, uploaded by SciShow, 26 February 2012,
MLA Inline: (SciShow, 2012)
APA Full: SciShow. (2012, February 26). Obesity [Video]. YouTube.
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Chicago Full: SciShow, "Obesity.", February 26, 2012, YouTube, 11:59,
Hello everyone. Today I'm here to tell you how you can lose four to nine pounds of belly fat in a single week by eating whatever you want and without doing a lick of exercise.


(Laughs) No, seriously, I'm here to tell you about Skinny Hank. For ten days you eat nothing but corn dogs and my patented fat-metabolizing peanut sauce wrapped in a flour tortilla. Make sure you take the stick out. You eat that, and exclusively that, you understand, for ten days. You might notice and that your face and feet start getting a little puffy, but don't worry about that, that will go away. After ten days of that, you can eat whatever you want, I promise, and bada-bam, you've got Ryan Gosling abs. I'd show you mine, but they're under there I promise, but we've got an agreement with our advertisers and I'm contractually bound to keep my shirt on.

Was that too much? I dunno if that was too much. It may have been to much. I apologize, but there was a point, in there somewhere amongst the Cheetos, and the point is that you can't go anywhere these days without someone telling you how you might be able to become thinner.

And yeah, partially it's because it's a really good way to sell people things, because we're very conscious about our bodies. But it's also because Americans, these days, are getting fat. And not just fat but obese and it's happening really really fast.

And this is a map of the United States. Starting in 1982, that's when the CDC starting collecting data on obesity, it was about at ten percent. And as time goes on, things start to get a little scary, and the whole country, but mostly focusing... Mississippi, wh- what is Mississippi doing? Stop doing that! You can see suddenly in the last thirty years, a lot of America has an average obesity rate above 30%. I don't want to hurt anyone's feelings or anything but we're fat, and we're getting fatter.

And it's not just Americans, we like to make fun of America particularly for getting so rotund so quickly, but it's the whole world, really, the whole developed world. We have 7 billion people on the earth right now, and a lot of people studying this think that 2.3 billion of them will be obese by 2015. I mean, that is.. a lot of people. 

And to be clear here, doctors don't go around hollering about how we need to lose weight because they're being paid off by the health foods industry, it's actually really bad for us. 

Carrying around a lot of extra body weight can kill you in many unpleasant ways, including our two favorite ways to die: heart disease and cancer, but also the new epidemic of type two diabetes. 

So being fat is objectively bad for you, but the question remains, how did it happen so quickly, and why did it happen so quickly? So, what's going on? Because the data on obesity would suggest that we're all just sitting around eating pork cracklings all day. That, I think was the very first pork crackling I've ever eaten in my life. And I can tell you why. Why do people eat these? That's not food.

And it's not just certain groups of people, it's everybody, it's little kids, and adult people, and it's rich people and it's poor people, and it's new immigrants to America and it's people whose ancestors came over on the Mayflower.

Conventional wisdom, and, uh, scientific rationality tells us that this is a numbers game, it's calories in versus calories out. It's the first friggin' law of thermodynamics, people. Our doctors never shut up about having us eat right, and exercise, and they're basically right, if we do that, we should be able to maintain a normal, healthy body shape. Whereas a quick perusal of the contents of your average grocery store will tell you, that we do not eat right, and a quick examination of the way that I, for example, live my life would indicate that we don't exercise very often. I... love to sit. 

But, doctors are now pretty sure that it is not in fact just diet and exercise, there has to be some other reason why America and the rest of the world is having this crazy obesity epidemic. Because scientists and doctors have been setting out again and again to prove that it's just diet and exercise, every time they come back and they pretty much fail. 

For example, in the year 2000, they took 1,700 schoolchildren from forty different schools, and they divided them into groups -- it's kinda a cruel thing to do, but they did it -- and they gave one of the groups better physical education and a better diet and they gave the other group less physical education and worse-- and the SAME, old diet, not a worse diet, but the one that they had always been eating, which if you remember school lunch, not good. At the end of three years of that, some of the smartest people in the world, armed with the best research equipment that you could buy, millions of dollars and lots of free time couldn't find a difference in the body mass index of those two groups of kids. 

So researchers are now setting their sights on overall macro-changes in the way humans are living, and even changes to our genes that may be defining why we are so obese now. Maybe we don't need to blame ourselves anymore. 

First reason: not enough sleep. It's hard to get precise data on how long people sleep at night, but our best guess is that since the 1960s, we've lost about 2 hours of sleep per night. We're just very busy people. And there are a bunch of studies that show that as you sleep less, your body mass index goes up. Which is why I like to sleep, like, 10 to 12 hours a day. And this is kinda hard data to figure out because obesity actually leads to sleep disorders, and so obese people have a harder time sleeping, so it's hard to figure out whether the lack of sleep is leading to the obesity or the obesity is leading to the lack of sleep. But scientists have actually done a pretty good job of figuring out that sleep deprivation has actually led to obesity. They've figured out one mechanism, at least, as to why. For example, there's a hormone called leptin, and there's another one, which I'll just put up here because I don't know how to pronounce it. And when you're sleep deprived, those hormones get all out of whack, and they start to tell your body that you're hungry when what in fact you probably need is not food, but sleep. 

Reason number two: Climate control. So this doesn't immediately makes sense, but we are warm-blooded mammals and we have to expend energy to keep our bodies at the temperature at which they can exist and if our bodies get too hot, then we die and if our bodies get too cold, then we die. In the past thirty years, our indoor spaces have become more and more exactly what we want them to be. We have really good climate control systems now. It's warm inside when it's cold outside and it's cold inside when it's warm outside. And don't get me wrong, I'm not going to argue against this, I love that, I love coming home and having it not be thirty degrees inside. But it does in fact take a huge amount of our calories to keep our bodies at the optimum temperature, and we're simply not expending those calories anymore because it's always 72 degrees inside. 

Reason number three: We all quit smoking. So to be clear: cigarettes are much more deadly than obesity. Facts is facts people, nicotine is an appetite suppressant so if you smoke, you eat less. And even worse, if you smoke and then stop, you eat more. And also in the same vein, I've heard that meth is a really great weight loss strategy, especially because you lose your teeth and hair, and those things have mass, so uh, you know... that- that... that's good.... I -I'm - what I'm saying here, is don't start smoking. uh, also don't do meth.

Speaking of crystal meth, number three (really four, Hank can't count) reason that we're all getting fatter: Industrial chemicals. every day you and I and everyone else in America are exposed to thousands of industrial chemicals. Resins, solvents, perfumes, dyes, all that lovely weird stuff they put in chicken nuggets. We swallow them, we inhale them, they absorb through our skin. Researchers for example are working with these poor, chubby little rats, exposing them to hexachlorobenzene which is an industrial pesticide and the rats that are exposed to hexachlorobenzene are significantly fatter than the ones that aren't, even when you feet the hexachlorobenzene rats half as much food as the control rats. That is unfortunate. 

Another reason why we may be getting fatter: your mom. The chances of you getting fat, unfortunately may be set even before you are born. First because overweight women tend to choose overweight men to father their offspring, and then you end up with two sets of overweight genes overlapping in your chromosomes. Also women who are overweight during their pregnancy or who contract gestational diabetes tend to give birth to babies who will later in life become obese. And the chances of being obese later in life are also affected by how old your mom was when she gave birth to you. The average age of a first-time mother jumped from 21 in 1970 to 25 in the year 2000. And some studies have come up with weird figures about this, like for every five years, a woman waits to have a baby, that baby is 14% more likely to become obese. And now, is the part where I explain to you why this is. Except, no one has any idea. And the final contender in the "your mom" category -- your mom, you can blame her for pretty much everything now -- is epigenetics, and we've done a whole episode on epigenetics, and you can click over here to go to that episode, and you'll learn all about all the things that your parents did to you before you were born. So you should watch that episode because it's totally gonna to make you be like, whaaa? Basically we used to think that your genes were your genes but it turns out that there's a bunch of information that's above the genome, which is what "epigenetics" mean, "above genetics" and that epigenetic information can be created just one generation before you, and totally change the way that your genomes are expressed. So basically the way that your mom ate food and whether she smoked cigarettes and how stressed out she was can all affect your chances of becoming an obese person. 

And finally, our last reason why people are obese: gut bacteria. So bacteria in our bodies are fantastic, and we like to think of bodies as big, independent individuals, but actually we're a symbiotic ecosystem up in here. There are actually more bacteria cells in our bodies than there are "us" cells. That's weird, huh? So the bacteria in our guts are super fantastic, really, great, hardworking guys, and they help us metabolize food, they help us create certain types of vitamins, and it turns out that skinny people tend to have more gut bacteria, and more different types of gut bacteria than obese people. I mean, the question is what do we do about that? I mean, it's not like we could take a healthy person's gut bacteria and put them... Actually, may-- you can do that, and it's really simple to do, it's just kinda hard to get people to agree to it. It's called a "fecal transplant" and it's exactly what it sounds like. So yeah, you take healthy gut bacteria, extract it from a healthy person's poop, and you just insert it into an unhealthy, uh, ecosystem of gut bacteria, and... it works. It can solve all sorts of problems, from like, really bad intestinal infections to, potentially, actually helping people with obesity. 

So in conclusion, skinny Hank, weight-loss peanut sauce is not going to help you, but we do now have a prescription for weight loss for you. 

Number one: get more sleep 
Number two: have your mom give birth to you when she's a little bit younger. 
Number three: see what you can do about before you're born making sure that your mom doesn't smoke, doesn't eat too much, and gets with skinnier guys. 
Number four: Do not heat or cool your house and think of all the money you'll save on utilities. 
And finally, number five: Move to a different planet that isn't laced with industrial chemicals. 
And yes, it's also probably a good idea to eat better and exercise more. 

If you're curious about where all the information for this video came from, we like to provide sources for you, I know they're down in the description. We're also available on Twitter and Facebook, and of course in the comments below, if you have any questions.