WEBVTT - Episode Six: The Truth About Health and Weight 0:00:05.080 --> 0:00:09.280 In two thousand five, Katherine Flegal and her colleagues did 0:00:09.480 --> 0:00:14.280 a research study. Catherine didn't think it was going to 0:00:14.360 --> 0:00:19.160 be controversial. Unfortunately, that was a miscalculation on my part. 0:00:19.440 --> 0:00:23.000 It was a huge deal. Catherine was a researcher at 0:00:23.000 --> 0:00:26.400 the Centers for Disease Control and Prevention at the time, 0:00:27.120 --> 0:00:30.000 and the study she was working on looked at weight 0:00:30.080 --> 0:00:36.880 associated deaths. It actually found something surprising, something that ran 0:00:37.080 --> 0:00:43.840 contrary to a pretty core idea about weight. Their analysis 0:00:43.840 --> 0:00:48.360 suggested that extra pounds might not be so bad for you. 0:00:49.320 --> 0:00:52.519 When they published what they found, their study kind of 0:00:52.560 --> 0:00:57.080 went viral. I had to get a separate phone line 0:00:57.120 --> 0:01:00.360 just to feel the calls from reporters and criticism them 0:01:00.480 --> 0:01:07.200 came really quickly. This one professor had begun preemptively contacting reporters. 0:01:07.480 --> 0:01:09.679 The study had been featured in the Journal of the 0:01:09.720 --> 0:01:14.640 American Medical Association, a highly respected journal that vetted the 0:01:14.680 --> 0:01:19.440 work before publishing it. But an academic was going around 0:01:19.680 --> 0:01:23.840 telling the press that Catherine's study was bad. So by 0:01:23.840 --> 0:01:26.040 the time they talked to me, they had already talked 0:01:26.120 --> 0:01:29.080 to another person who had said that my stuff was 0:01:29.319 --> 0:01:33.720 rubbish and completely wrong and fatally flawed. And things like that, 0:01:34.040 --> 0:01:37.479 And something similar happened at a scientific meeting not long 0:01:37.520 --> 0:01:40.720 after the paper came out, and this other professor took 0:01:40.760 --> 0:01:43.959 the stage when he wasn't supposed to be speaking and 0:01:44.800 --> 0:01:48.120 just issue the condemnation of our article, just out of 0:01:48.120 --> 0:01:52.640 the blue. So what was everyone so angry about. Anyway, 0:01:52.800 --> 0:01:55.520 We were trying to estimate the proportion of this in 0:01:55.560 --> 0:01:59.240 the United States that were associated with different bm I levels. 0:01:59.520 --> 0:02:03.480 Cavin specifically for a CDC division known as the National 0:02:03.560 --> 0:02:08.040 Center for Health Statistics. That's the agency responsible for coming 0:02:08.120 --> 0:02:12.480 up with data to help make Americans healthier, And like 0:02:12.680 --> 0:02:17.160 Catherine said, she was focused on figuring out how many 0:02:17.240 --> 0:02:21.560 deaths in America were associated with different b m I s, 0:02:22.320 --> 0:02:26.959 or body mass index, which is basically a mathematical formula 0:02:27.120 --> 0:02:32.880 for estimating a person's body fat. In other words, Catherine 0:02:32.919 --> 0:02:39.119 was investigating the link between weight and death. But these 0:02:39.120 --> 0:02:43.280 weren't just numbers something to stick on a website or 0:02:43.480 --> 0:02:47.840 pamphlet somewhere and forget about a lot of things done 0:02:47.960 --> 0:02:51.480 at the National Center for Health Statistics are supposed to 0:02:51.480 --> 0:02:57.720 influence policy. At the time, body weight was already emerging 0:02:57.919 --> 0:03:02.679 as public health enemy number one. The deadly impact of obesity. 0:03:02.800 --> 0:03:06.639 The toll on Americans far greater than previously thought. Why 0:03:06.680 --> 0:03:09.960 are Americans so fat? The United States is the world's 0:03:10.000 --> 0:03:13.960 baddest developed nation, with an obesity right double of that 0:03:13.960 --> 0:03:18.600 in many European countries. The CDC had declared obesity a 0:03:18.800 --> 0:03:25.960 growing epidemic years earlier, and Catherine and her colleagues weren't 0:03:26.040 --> 0:03:29.080 the first to look at the subject. The paper that 0:03:29.240 --> 0:03:32.600 came out before ours estimated that obesity was about to 0:03:32.639 --> 0:03:34.800 overtake smoking is the major cause of death in the 0:03:34.880 --> 0:03:39.080 United States. Remember, at this point, there was also tons 0:03:39.160 --> 0:03:43.280 of awareness that smoking is bad for you, So the 0:03:43.400 --> 0:03:47.760 idea that being heavy could be more dangerous than smoking 0:03:49.040 --> 0:03:53.720 that really sent people into a tail spin. It looked 0:03:53.760 --> 0:03:58.560 like America had this big weight problem. But when Catherine 0:03:58.560 --> 0:04:01.880 and her colleagues sat down to do their own analysis, 0:04:02.640 --> 0:04:06.720 they came to a very different conclusion. Our paper didn't 0:04:06.720 --> 0:04:10.320 suggest that the city associated deaths were anywhere. They're likely 0:04:10.360 --> 0:04:13.240 to overtake smoking as a major cause of death. Using 0:04:13.320 --> 0:04:19.480 data from what's called the National Health and Nutrition Examination Survey, 0:04:19.560 --> 0:04:23.360 they examined the health of tens of thousands of Americans. 0:04:24.480 --> 0:04:28.760 They also tracked how many of those participating over the 0:04:28.880 --> 0:04:31.719 years had died. If you look at the number of 0:04:31.760 --> 0:04:34.279 deaths and you adjust for all these things like age 0:04:34.320 --> 0:04:38.479 and gender and socio economic data and so on, we 0:04:38.560 --> 0:04:41.440 get this many more desks than would be expected, and 0:04:41.680 --> 0:04:44.720 this many fewer deaths would be expected, making that comparison 0:04:44.760 --> 0:04:48.120 to normal weight. They basically wanted to figure out how 0:04:48.160 --> 0:04:53.839 many more people considered overweight or obese we're dying then 0:04:53.960 --> 0:04:56.640 would have been expected if they had been at a 0:04:56.920 --> 0:05:01.159 so called normal weight A. When they crunched the numbers, 0:05:01.800 --> 0:05:06.000 Katherine and co. Found that obesity wasn't about to pass 0:05:06.080 --> 0:05:09.120 smoking as a top cause of death in the US, 0:05:09.960 --> 0:05:14.400 not even close. They also found that the number of 0:05:14.440 --> 0:05:17.840 deaths connected to higher b m I s is actually 0:05:17.960 --> 0:05:21.200 pretty low, so it was a very different result. They 0:05:21.240 --> 0:05:25.320 find that fewer people with a b m I classified 0:05:25.360 --> 0:05:30.360 as overweight We're dying than would have been expected at 0:05:30.400 --> 0:05:33.400 a normal weight b m I. We didn't say that 0:05:33.480 --> 0:05:37.120 these things are caused or were protected, or that or 0:05:37.160 --> 0:05:39.479 we is protected. We just reported the numbers. Now, people 0:05:39.480 --> 0:05:41.520 have a lot of takeaways from that, but I don't 0:05:41.520 --> 0:05:44.599 feel responsible for all their takeaways. But to say the 0:05:44.680 --> 0:05:50.159 least they're finding was really unexpected. After all, carrying around 0:05:50.279 --> 0:05:54.000 extra pounds is supposed to be bad for you. That's 0:05:54.040 --> 0:05:58.360 the whole basis for medical categories like overweight or obese. 0:05:59.400 --> 0:06:03.440 This is the scientific foundation on which weight lost empires 0:06:03.520 --> 0:06:08.640 have been built. Where did that idea come from? Anyway? 0:06:09.080 --> 0:06:13.320 And is it even true? What Catherine and her team 0:06:13.560 --> 0:06:18.440 found called at least some of this into question, so 0:06:18.760 --> 0:06:23.599 other scientists freaked out. It seems like they decided the 0:06:23.680 --> 0:06:28.000 only explanation was that Catherine and her team had messed 0:06:28.080 --> 0:06:33.040 up somehow. That was easier for them to swallow than 0:06:33.160 --> 0:06:37.520 considering the opposite, that Catherine and her team could actually 0:06:37.560 --> 0:06:42.559 be right, that the relationship between weight and health could 0:06:42.600 --> 0:06:48.200 be different. The funny thing is this Catherine and her 0:06:48.240 --> 0:06:53.279 colleagues hadn't meant to call into question the very foundations 0:06:53.320 --> 0:06:56.800 of weight science. We just blundered into this. I mean, 0:06:56.839 --> 0:07:00.200 we weren't trying to cause a fire. Back to what 0:07:00.360 --> 0:07:04.080 Catherine and her colleagues found, It wasn't that there was 0:07:04.360 --> 0:07:08.800 no link between b m I and death exactly, but 0:07:09.080 --> 0:07:13.000 that link existed among people with higher b m I 0:07:14.000 --> 0:07:18.400 of thirty or higher, which is the cutoff for obesity, 0:07:18.640 --> 0:07:23.640 and especially thirty five or higher, and when the researchers 0:07:23.760 --> 0:07:27.800 added it all up, the total number of deaths tied 0:07:27.840 --> 0:07:33.000 to these categories of overweight and obees turned out to 0:07:33.080 --> 0:07:38.440 be pretty small. More people were dying in those years 0:07:38.480 --> 0:07:43.320 from car crashes and gun violence, and more people were 0:07:43.680 --> 0:07:47.800 definitely dying from smoking, so there was a very large difference. 0:07:48.400 --> 0:07:52.680 Before Catherine published the research, she also looked at a 0:07:52.760 --> 0:07:56.680 bunch of other studies. She wanted to know whether her 0:07:56.720 --> 0:08:03.160 team's findings were unusual. After all, their paper contradicted what 0:08:03.360 --> 0:08:07.400 most people think about weight and health, at least when 0:08:07.440 --> 0:08:11.560 it comes to the category of overweight. But it turned 0:08:11.600 --> 0:08:15.720 out that there's wasn't even the first study with findings 0:08:15.760 --> 0:08:17.720 like these. There's a lot of other studies that have 0:08:17.720 --> 0:08:21.000 shown this already, so it's not a big deal. Those 0:08:21.040 --> 0:08:24.640 other studies had also found little risk of death associated 0:08:24.680 --> 0:08:28.800 with having a b m I classified as overweight, But 0:08:28.840 --> 0:08:31.920 it was Catherine's study that for some reason really struck 0:08:31.920 --> 0:08:35.360 a nerve, and a lot of those tacks were coming 0:08:35.559 --> 0:08:42.840 from academics at one particular institution, Harvard, especially this one 0:08:42.880 --> 0:08:48.240 guy Walter Willet. At the time, Walter was the chair 0:08:48.280 --> 0:08:53.520 of the nutrition department. After another paper, Catherine wrote, he 0:08:53.559 --> 0:08:57.640 went around calling her work a pile of rubbish and 0:08:57.640 --> 0:09:03.040 said people should ignore it. The prestigious journal Nature actually 0:09:03.160 --> 0:09:08.880 ended up writing an editorial basically criticizing Walter's comments and 0:09:09.000 --> 0:09:13.680 saying he was oversimplifying the science. But there was more 0:09:13.720 --> 0:09:17.319 than just that. And then the Harvard School of Public 0:09:17.320 --> 0:09:22.560 Health group that was mainly, although not exclusively, the antagonists here, 0:09:23.280 --> 0:09:27.560 they decided to schedule a symposium at Harvard to basically 0:09:27.559 --> 0:09:30.520 to show what was wrong with my article. That's right. 0:09:31.120 --> 0:09:36.080 Researchers opposed Catherine's findings so fiercely that they put together 0:09:36.200 --> 0:09:39.439 a whole event just to talk about how much they 0:09:39.480 --> 0:09:44.240 hated it. And Catherine says that the conference organizers didn't 0:09:44.280 --> 0:09:47.480 even make it possible for her and her co authors 0:09:47.520 --> 0:09:52.160 to attend. As you can imagine, all of this was 0:09:52.640 --> 0:09:56.080 a lot for Catherine. This is getting really stressful. I 0:09:56.080 --> 0:09:58.360 had a very high adrenaline level, I would say, because 0:09:58.400 --> 0:10:01.720 I was always finding the weird attacks in places that 0:10:01.800 --> 0:10:04.920 I just would not have expected, like Wikipedia. The gist 0:10:04.920 --> 0:10:07.640 of all this criticism was that there were things Katherine 0:10:07.679 --> 0:10:11.360 and her colleagues had simply missed. They had found. The 0:10:11.360 --> 0:10:14.680 people living in bigger bodies were dying at similar rates 0:10:14.720 --> 0:10:19.239 to those in smaller bodies. But like I said earlier, 0:10:19.760 --> 0:10:23.200 it was easier for prominent scientists to imagine that Katherine 0:10:23.280 --> 0:10:27.040 and co. Were wrong, then that they're finding could be true. 0:10:28.480 --> 0:10:32.679 The explanation critics landed on, according to news coverage at 0:10:32.679 --> 0:10:36.880 the time, was that their numbers must have been off. 0:10:38.040 --> 0:10:41.719 After all, people can be thin because they're sick with 0:10:41.840 --> 0:10:47.880 diseases like cancer, or because they're elderly. The critics said 0:10:48.080 --> 0:10:51.720 that these sorts of things must have thrown off the study. 0:10:52.840 --> 0:10:57.080 They also said that Katherine's team didn't use enough long 0:10:57.200 --> 0:11:03.000 term data, but Katherine says, no, that wasn't it at all. 0:11:03.720 --> 0:11:06.160 The issue was that people had already meet up their 0:11:06.160 --> 0:11:10.480 minds about weight and health, and Catherine was undermining those 0:11:10.480 --> 0:11:16.280 preconceived notions. Catherine was basically an atheist, renouncing the gospel 0:11:16.360 --> 0:11:19.960 about weight and health. There's this real drive to say 0:11:20.080 --> 0:11:22.440 anything finding like that is unusual. It needs to be 0:11:22.440 --> 0:11:25.839 explained away. We need to get rid of this. How 0:11:25.840 --> 0:11:27.440 do we get rid of it? We've got to say, well, 0:11:27.440 --> 0:11:29.520 maybe it's because of ages, or maybe it's because of this. 0:11:30.040 --> 0:11:32.320 It's because of that, you know. So there's all you 0:11:32.320 --> 0:11:36.160 have to explain away in convenient findings. Catherine says this 0:11:36.320 --> 0:11:40.600 stuff wasn't really an issue, and in fact, she and 0:11:40.640 --> 0:11:44.560 her team said right in their paper that factors like 0:11:44.679 --> 0:11:48.960 illness and duration of follow up didn't have a big impact. 0:11:49.679 --> 0:11:52.160 So this was all based on pretty much nothing, But 0:11:52.200 --> 0:11:55.439 it was very influential, and this kind of stuff went 0:11:55.440 --> 0:12:00.160 on literally for years. Disagreements like these are actually a 0:12:00.280 --> 0:12:04.560 really key part of the scientific process. The whole point 0:12:04.760 --> 0:12:08.440 is to go back and forth about findings so people 0:12:08.480 --> 0:12:12.480 can trust that they're accurate. But the way Catherine describes it, 0:12:13.080 --> 0:12:16.920 the criticism crossed the line. What could have been a 0:12:17.000 --> 0:12:24.120 legitimate scientific debate evolved. Misinformation started flying, Like when one 0:12:24.160 --> 0:12:28.360 group claimed that Catherine's findings were renounced by the CDC, 0:12:29.679 --> 0:12:33.559 she says they weren't. When I asked the CDC about it, 0:12:33.679 --> 0:12:36.120 they didn't get back to me. So there's just all this, 0:12:36.280 --> 0:12:39.360 at least falsehoods lying around, and I didn't know what 0:12:39.400 --> 0:12:42.040 to do about them. Some of it was just kind 0:12:42.040 --> 0:12:46.719 of disrespectful about Catherine's skills as a scientist. The one 0:12:46.760 --> 0:12:49.960 who was kind of insults saying that my paper was 0:12:50.080 --> 0:12:53.680 my faintly flawed. That was nonsense. It was rubbish, that 0:12:54.120 --> 0:12:58.000 we made very simple errors that were completely wrong. Harvard 0:12:58.040 --> 0:13:01.680 didn't return a request for comment by our deadline. In 0:13:01.760 --> 0:13:05.640 an email to me, Walter Willett said that Katherine's paper 0:13:05.960 --> 0:13:10.920 quote was causing serious confusion among physicians and patients, with 0:13:11.000 --> 0:13:16.720 potentially dangerous clinical and public health consequences. He also says 0:13:16.800 --> 0:13:21.480 that many large analyzes have refuted the findings showing that 0:13:21.600 --> 0:13:26.240 overweight and obesity have poor health effects. It's clear from 0:13:26.240 --> 0:13:31.200 talking to Catherine that these criticisms rankled her because she 0:13:31.320 --> 0:13:34.800 cares a lot about the science. She retired from the 0:13:34.840 --> 0:13:40.439 CDC in and is currently a consulting professor at Stanford. 0:13:41.480 --> 0:13:47.400 But the attacks became personal too. Lisa and Darovitch, who 0:13:47.480 --> 0:13:50.760 was a PhD student at Harvard about a decade ago, 0:13:51.640 --> 0:13:58.000 said a professor there even criticized Katherine's weight, saying that 0:13:58.120 --> 0:14:01.000 was why her work couldn't be trust stid. I got 0:14:01.080 --> 0:14:04.199 very stressed trying to deal with this stuff and trying 0:14:04.200 --> 0:14:07.920 to respond to things that people were saying. This was 0:14:08.120 --> 0:14:12.679 Catherine's scientific reputation on the line, This is her career, 0:14:13.600 --> 0:14:18.000 and this loud chorus of scientific feedback is saying legal 0:14:18.120 --> 0:14:20.880 must be wrong. Legal is wrong. Legal is wrong. She 0:14:20.960 --> 0:14:23.440 must be wrong, or this must be wrong, or therefore 0:14:23.480 --> 0:14:28.000 she's wrong. But what if Catherine wasn't wrong? What if 0:14:28.040 --> 0:14:33.080 the dangers of being heavy have been overstated or misrepresented? 0:14:34.400 --> 0:14:38.200 A small but vocal contingent of experts and advocates say 0:14:38.320 --> 0:14:43.360 just that. They argue that weighing more isn't inherently bad 0:14:43.400 --> 0:14:47.280 for you. In fact, when people say that, they are 0:14:47.360 --> 0:14:53.880 mixing up correlation and causation, a classic scientific error. This 0:14:53.960 --> 0:14:58.080 is obviously counter to the predominant thinking. But the idea 0:14:58.200 --> 0:15:00.600 here is that we have been folk using on the 0:15:00.640 --> 0:15:05.920 scale too much and not enough on healthy behaviors. Our 0:15:06.000 --> 0:15:10.240 weight bias has become a major blind spot, something that 0:15:10.320 --> 0:15:14.480 keeps us reciting the same old lines about weight and health, 0:15:15.280 --> 0:15:19.280 even as a body of scientific evidence suggests that this 0:15:19.320 --> 0:15:23.440 way of thinking is wrong. We're going to get into 0:15:23.480 --> 0:15:26.720 that in this episode, and we're going to take a 0:15:26.880 --> 0:15:31.600 close look at evidence behind it. I'm Bloomberg News health 0:15:31.680 --> 0:15:37.560 reporter Emma Court and from the Prognosis podcast This is 0:15:37.640 --> 0:15:51.520 Losing It. There's some things pretty much everyone will agree 0:15:51.800 --> 0:15:56.120 is true. The earth is round, the sky is blue, 0:15:57.040 --> 0:16:01.920 and weighing more is bad for you. That's the message 0:16:02.000 --> 0:16:05.720 we get in a million overt and subtle ways every 0:16:05.760 --> 0:16:09.920 single day. Just look at who gets featured on the 0:16:09.960 --> 0:16:15.400 cover of fitness magazines. And then there's the actual messages 0:16:15.840 --> 0:16:20.480 people with bigger bodies get from their doctors, from friends 0:16:20.520 --> 0:16:25.280 and family, and even sometimes from random people on the street. 0:16:26.520 --> 0:16:31.800 Lose weight and you'll be healthier. Tracy Man, a psychologist 0:16:31.880 --> 0:16:34.760 who runs a health and eating lab at the University 0:16:34.800 --> 0:16:39.240 of Minnesota, puts it really well. The air we breathe 0:16:39.400 --> 0:16:43.320 is weight stigma. Treating people in bigger bodies poorly is 0:16:43.360 --> 0:16:46.760 so common that lots of people don't even notice it 0:16:47.280 --> 0:16:50.360 or think of it as discrimination. We've been brought up 0:16:50.400 --> 0:16:54.600 with views that it's not okay to be obese and 0:16:54.640 --> 0:16:57.680 that you need to be thin, and you, at least 0:16:57.840 --> 0:17:01.920 a minimum need to be trying to be thin. Tracy 0:17:02.000 --> 0:17:05.520 thinks that's why diets keep getting pushed over and over 0:17:05.560 --> 0:17:08.919 and over again, even though they don't really work for 0:17:09.000 --> 0:17:13.639 long term weight loss, not for most people anyway. Like 0:17:13.920 --> 0:17:16.680 she says, even if the deck is stacked against you, 0:17:17.359 --> 0:17:20.479 the expectation is that you should at least try to 0:17:20.560 --> 0:17:25.479 be thin. The message is persistent. Getting thin should be 0:17:25.520 --> 0:17:30.720 your goal, otherwise you're doing it wrong. The way Tracy 0:17:30.840 --> 0:17:35.720 put it really struck me. Wait, stigma is the air 0:17:35.760 --> 0:17:39.879 we breathe, and so is the idea that living in 0:17:39.920 --> 0:17:45.320 a bigger body means you're unhealthy. Think about it. When 0:17:45.359 --> 0:17:48.719 did you first hear that weighing more is bad for you? 0:17:50.280 --> 0:17:54.040 And how often have you heard it since then? Every month, 0:17:54.760 --> 0:17:59.240 every hour? Did you ever question why that's the case 0:18:00.400 --> 0:18:03.840 or have you always just accepted it at face value? 0:18:05.040 --> 0:18:08.160 I'm guessing that for most of us it's the latter. 0:18:09.080 --> 0:18:11.639 I've just heard it said that that you can be 0:18:11.640 --> 0:18:14.840 fat and healthy. Actually you can't think. I'm sure that 0:18:14.880 --> 0:18:18.359 you're excess if that is unhealthy, I don't think anyone 0:18:18.520 --> 0:18:21.000 is agons off with it. But how do we know 0:18:21.400 --> 0:18:26.520 that being heavy is bad for you? Tracy and others say, 0:18:26.560 --> 0:18:32.360 we actually don't. We don't know that. We know that 0:18:32.400 --> 0:18:37.360 people at heavier weights can have health problems, but they 0:18:37.440 --> 0:18:42.479 don't always, and it's not clear that weight itself is 0:18:42.560 --> 0:18:47.560 the issue. Here's the deal. Higher B M E s 0:18:47.680 --> 0:18:51.360 are at greater risk for a lot of different diseases, 0:18:51.680 --> 0:18:56.560 medical conditions, and depth. It's a really long list, so 0:18:56.720 --> 0:19:00.400 I'll just read it off the cdc S website. High 0:19:00.400 --> 0:19:06.719 blood pressure, high cholesterol, type two diabetes, coronary heart disease, stroke, 0:19:07.400 --> 0:19:13.320 gall bladder disease, ost arthritis, sleep apnian, breathing problems, many 0:19:13.359 --> 0:19:18.760 types of cancer, mental illness like depression and anxiety. You 0:19:18.800 --> 0:19:21.880 get the idea. You hear this kind of thing all 0:19:21.880 --> 0:19:25.040 the time, like from doctors who say, all of the 0:19:25.119 --> 0:19:30.120 chronic diseases that we deal with, high blood pressure, cardiovascular disease, diabetes, 0:19:30.440 --> 0:19:33.720 they're all related to weight problems. The CDC also lists 0:19:33.720 --> 0:19:37.200 some more vague sounding things as risks if you're heavier, 0:19:38.040 --> 0:19:42.399 like low quality of life and body pain and difficulty 0:19:42.520 --> 0:19:47.440 with physical functioning. You might be wondering what the connection 0:19:47.680 --> 0:19:52.879 is between weight and all these problems, the why of 0:19:52.960 --> 0:19:59.000 it all. Doctors and scientists are specifically concerned with extra fat, 0:20:00.000 --> 0:20:03.080 which they say can put lots of stress on the body, 0:20:04.200 --> 0:20:09.120 including pressure on bones and joints, and fat cells can 0:20:09.240 --> 0:20:15.080 lead to inflammation, affecting things like regulation of blood sugar levels, 0:20:15.280 --> 0:20:19.960 which can lead to diabetes. But again, the conditions I 0:20:20.080 --> 0:20:25.679 listed earlier are risks associated with higher weights, Like the 0:20:25.760 --> 0:20:30.679 doctor we just heard talking said, heart disease and diabetes 0:20:30.840 --> 0:20:36.200 and all the rest are linked with weight or associated 0:20:36.280 --> 0:20:42.159 with weight the reason for all that careful language. Here's 0:20:42.200 --> 0:20:47.719 tracy again. Weight is correlated with many problems, but correlation 0:20:47.960 --> 0:20:53.320 does not mean it's causing those problems. Correlation is not causation. 0:20:54.160 --> 0:20:58.240 That's kind of a big rule in statistics. Admittedly, I 0:20:58.280 --> 0:21:00.959 haven't been in a math class in a long time, 0:21:01.880 --> 0:21:05.840 but I remember pretty clearly that in high school one 0:21:05.880 --> 0:21:09.160 of our teachers actually had us banging on our desks 0:21:09.280 --> 0:21:16.920 and enchanted. Correlation is not causation. Correlation is not causation. Now, 0:21:17.119 --> 0:21:20.879 there are a lot of places where conflating correlation and 0:21:20.920 --> 0:21:26.000 causation becomes a problem. One of the classic examples has 0:21:26.040 --> 0:21:30.840 to do with ice cream and murder. Ice Cream sales 0:21:31.000 --> 0:21:37.160 increase in the summer, and so do the number of murders. Therefore, 0:21:37.920 --> 0:21:44.080 ice cream causes murders. Seems straightforward enough, but of course 0:21:44.480 --> 0:21:48.600 that's wrong. Murders and ice cream consumption both go up 0:21:48.640 --> 0:21:53.520 at the same time because of a third factor, rising temperatures. 0:21:54.440 --> 0:21:58.840 When it's warm, people eat ice cream, and just generally 0:21:59.040 --> 0:22:02.439 people are out and about more. They're doing more of 0:22:02.520 --> 0:22:08.440 lots of kinds of activities, including apparently committing felonies. Ice 0:22:08.480 --> 0:22:13.600 Cream may be delicious, but it is not to blame again, 0:22:13.840 --> 0:22:18.560 Correlation is not causation, and with weight, just like with 0:22:18.640 --> 0:22:22.480 ice cream and murders, there are other factors that could 0:22:22.520 --> 0:22:28.280 help explain what's going on, things like lifestyle. More on 0:22:28.359 --> 0:22:33.160 that in a minute. We want to understand why so 0:22:33.240 --> 0:22:38.359 many diseases occur so we can prevent them, and many 0:22:38.400 --> 0:22:43.880 diseases are associated with weight. Studies have also shown that 0:22:44.000 --> 0:22:49.160 when people lose weight, they lower their odds of developing conditions, 0:22:49.200 --> 0:22:56.200 including diabetes, and improve things like cholesterol levels. Evidence seems 0:22:56.320 --> 0:23:01.520 clear right losing weight is the way to improve your health. 0:23:02.880 --> 0:23:06.160 But the experts and advocates I spoke with for this 0:23:06.200 --> 0:23:11.439 episode tell a very different story. They say that we 0:23:11.720 --> 0:23:17.960 unfairly blame weight for really complex scientific questions and treat 0:23:18.080 --> 0:23:23.480 dieting as a quick fix. Except it's actually not a 0:23:23.560 --> 0:23:28.679 quick fix because, as we've learned in this podcast, losing 0:23:28.720 --> 0:23:34.919 weight long term is a really challenging and almost impossible enterprise. 0:23:36.560 --> 0:23:41.120 So what could be actually causing these diseases and other 0:23:41.200 --> 0:23:46.399 issues if not weight? Now, this is a subject that's 0:23:46.680 --> 0:23:52.520 really charged, so I ask you to reserve judgment. Here 0:23:52.520 --> 0:23:56.560 are experts out. It turns out that there are a 0:23:56.600 --> 0:24:00.920 lot of things that are correlated with weight, aren't so 0:24:01.000 --> 0:24:05.720 good for you, including being sedentary. Sedentary a k a. 0:24:05.960 --> 0:24:09.719 Not moving around a lot. This is actually a pretty 0:24:09.720 --> 0:24:12.879 big issue, and not just for people at heavier weights. 0:24:14.119 --> 0:24:18.800 Many many people live sedentary lives. We drive to work, 0:24:19.480 --> 0:24:23.200 we sit at a computer, that kind of thing. In fact, 0:24:23.359 --> 0:24:25.720 people in the Western world have been living like this 0:24:25.920 --> 0:24:30.320 for hundreds of years. We talked about that in episode two, 0:24:30.760 --> 0:24:34.720 how the Industrial Revolution shaped the conditions of modern life 0:24:34.800 --> 0:24:38.280 and modern dieting and made us all a lot more 0:24:38.359 --> 0:24:42.359 likely to just sit around on our butts all day. 0:24:43.440 --> 0:24:45.720 At a certain point, it starts to get tough to 0:24:45.800 --> 0:24:49.640 separate out how we live from how much we weigh. 0:24:49.920 --> 0:24:51.879 You get into a little bit of a chicken or 0:24:51.880 --> 0:24:56.800 egg thing. Here's Glenn Geyser, a professor of exercise physiology 0:24:56.920 --> 0:25:01.320 at Arizona State University. People who are overweight or beasts 0:25:01.640 --> 0:25:04.600 tend to be less physically active. They tend to eat 0:25:04.680 --> 0:25:09.159 unhealthier diets. That is on average what we see. But 0:25:09.240 --> 0:25:12.800 that doesn't mean that the weight is the problem. Means 0:25:12.840 --> 0:25:17.880 that it's probably the lifestyle. The problem is lifestyle, not weight. 0:25:18.560 --> 0:25:21.440 This is the problem that we have in America. We've 0:25:21.440 --> 0:25:23.960 got this disconnect. We think weight is the big issue 0:25:23.960 --> 0:25:28.359 when it's really not. It's the lifestyle that oftentimes goes without. 0:25:28.800 --> 0:25:33.000 Of course, weight is way more complicated than just lifestyle. 0:25:33.760 --> 0:25:37.320 Not all of it is in our hands. Your genetics, 0:25:37.400 --> 0:25:42.040 for example, are a really important factor too, but you 0:25:42.080 --> 0:25:47.919 can actually change your lifestyle. Higher weights are also connected 0:25:47.960 --> 0:25:52.720 to other things too. Here's tracy again. It's also correlated 0:25:52.760 --> 0:25:58.600 with poverty, and there's a ton of research showing links 0:25:58.600 --> 0:26:04.679 between poverty and health problems. Heavier people also experienced stigma. 0:26:04.960 --> 0:26:09.000 Often they're treated worse because of how they look. That 0:26:09.240 --> 0:26:13.359 has been shown to be correlated to health problems, even 0:26:13.440 --> 0:26:17.199 controlling for whatever the person weighs, and there's lots of 0:26:17.240 --> 0:26:20.720 reasons for that. People in bigger bodies often go to 0:26:20.760 --> 0:26:24.560 the doctor and just get told to lose weight, almost 0:26:24.600 --> 0:26:28.200 as a reflex. Doctors just assumed that weight is the 0:26:28.320 --> 0:26:32.560 issue and don't investigate what might actually be causing someone's 0:26:32.560 --> 0:26:37.000 health issues. And when things like that happen, people get 0:26:37.119 --> 0:26:43.480 sicker and they also avoid doctors. That's wait stigma in action. 0:26:44.760 --> 0:26:49.600 Wait stigma is incredibly prevalent, not just for medical providers. 0:26:50.200 --> 0:26:53.000 Doctors are the number two source of fat phobia and 0:26:53.000 --> 0:26:57.760 wait stigma outside of family. This is Veronica Garnett. Veronica 0:26:57.800 --> 0:27:00.119 is a dietitian and one of the leaders of a 0:27:00.160 --> 0:27:04.680 group called the Association for Size Diversity and Health or ASDA. 0:27:04.800 --> 0:27:07.159 And then if you're in a fat phobic we live 0:27:07.160 --> 0:27:10.960 in a fat phobic society and world. It is stressful 0:27:11.200 --> 0:27:14.040 to be treated poorly because of the way you look. 0:27:15.000 --> 0:27:18.639 Lots of evidence has suggested that stress is not good 0:27:18.680 --> 0:27:22.520 for people and can have all sorts of terrible effects 0:27:22.560 --> 0:27:26.000 on their health. It starts to feel like some kind 0:27:26.040 --> 0:27:31.840 of vicious cycle. We assume people's weight makes them unhealthy, 0:27:31.960 --> 0:27:37.240 and those assumptions then harm their health. It's also stressful 0:27:37.280 --> 0:27:40.879 to navigate a world that, just in general, was not 0:27:41.080 --> 0:27:46.000 designed to accommodate your body. Here's Annie Jansen, another one 0:27:46.119 --> 0:27:50.640 of asda's leaders. Annie is also a dietitian and has 0:27:50.640 --> 0:27:54.720 a master's in public health. Fat people's health is impacted 0:27:54.760 --> 0:27:59.120 by fat phobian weight stigma. Even outside of the medical realm. 0:27:59.200 --> 0:28:02.520 Chairs are are not accessible to all people. In restaurants, 0:28:02.880 --> 0:28:07.520 um and theaters, and other public spaces. UM people face 0:28:07.880 --> 0:28:12.960 direct hate and comments about their bodies when they're out 0:28:13.000 --> 0:28:16.879 in public, limiting their ability to participate in public life. 0:28:17.600 --> 0:28:21.439 Doctors are people affected by bias like any other person, 0:28:22.280 --> 0:28:25.920 and bias can also affect the scientists doing the studies. 0:28:26.600 --> 0:28:31.119 It's easy for people to find diseases correlated to higher 0:28:31.160 --> 0:28:34.600 weights when the research itself is biased um, and it's 0:28:34.600 --> 0:28:37.639 easy for people to accept that and not really be 0:28:37.760 --> 0:28:42.000 critical about how well done those studies are. There's one 0:28:42.040 --> 0:28:47.840 more thing, a really important thing. As we've established by now, 0:28:48.400 --> 0:28:51.640 people who live in bigger bodies are facing all this 0:28:51.960 --> 0:28:57.480 pressure to diet and lose weight. Losing weight isn't usually sustainable, 0:28:57.680 --> 0:29:02.800 though so many people gave weight back. This is known 0:29:03.000 --> 0:29:08.360 as yo yo dieting, or, in more scientific terms, weight cycling. 0:29:09.560 --> 0:29:13.600 There's actually a lot of evidence connecting it with health problems. 0:29:14.200 --> 0:29:17.840 Weight cycling is an independent risk factor for diabetes, hypertension, 0:29:17.960 --> 0:29:22.480 insulin resistance, and a slipidemia, which is essentially high bad 0:29:22.520 --> 0:29:27.600 cholesterol and or good are low good cholesterol. You'll notice 0:29:27.640 --> 0:29:31.440 that all of those disease listed are typically diseases associated 0:29:31.440 --> 0:29:35.960 with higher BMI. This is again something that studies have found. 0:29:36.840 --> 0:29:39.720 I know you're sick of me saying it, but correlation 0:29:39.880 --> 0:29:44.840 is not causation. So how come with weight we've thrown 0:29:44.920 --> 0:29:50.040 out this incredibly basic scientific principle. A lot of doctors 0:29:50.080 --> 0:29:53.400 and scientists would say that we have it, and that 0:29:53.480 --> 0:29:58.600