Most Replayed Moment: Is There A Safe Amount Of Alcohol? What Happens To The Body When You Drink!

Sarah Wakeman is a physician and Medical Director specialising in substance use and addiction treatment, working on the front lines of alcohol-related harm. In this Moment, she breaks down what the science actually says about having just one drink, debunks old narratives and reveals what alcohol is really doing to the body. Listen to the full episode here! Spotify: https://g2ul0.app.link/BVLeOxhOTZb Apple: https://g2ul0.app.link/vw2IpvzOTZb Watch the Episodes On YouTube: ⁠⁠https://www.youtube.com/c/%20TheDiaryOfACEO/videos Sarah Wakeman: https://www.massgeneral.org/doctors/19383/sarah-wakeman

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:04Steven Bartlett?

  So alcohol.

• 0:04Speaker 01

  Yes.

• 0:05Steven Bartlett?

  There's, I mean, alcohol's been on a journey.

• 0:08Speaker 01

  Yes.

• 0:09Steven Bartlett?

  It's been on a journey in terms of society's opinion about it. Can you take me on that journey and tell me where we are now?

• 0:15Speaker 01

  Yeah.

• 0:16Steven Bartlett?

  And when I'm saying that, I'm talking about society's opinion on its health benefits and what it is. And then also what we're getting wrong now about alcohol.

• 0:24Speaker 01

  Yeah, yeah. I mean, the journey of alcohol is fascinating. So first, I think they think of this as a relatively modern thing. But, you know, archaeologists have discovered like beer-making equipment in hunter-gatherers' cave dwellings from 13,000 years ago. That's wild.

• 0:39Steven Bartlett?

  Wow.

• 0:39Speaker 01

  Like 13,000 years of people figuring out how to make beer. You know, you look at China, 9,000 years ago. It was really about like a spiritual journey or a social thing. It was never really about health. At some point, we started talking about this as something that is good for your health. Like, drink red wine, it's going to improve your health. And that's where I think we got wrong. And the reason why was actually from how we were looking at the data. So first, if you look at only one health condition, there are some health conditions where a moderate amount of alcohol actually improves your health. But it was also how people were conducting the studies. So in most of those studies, what people do is they take like a massive population, tens of thousands of people, where we have some data where they're reporting how much alcohol they used. And then we look at health risks over time. And scientists would lump people into sort of non-drinkers versus light drinkers, moderate

• 1:24Speaker 01

  drinkers, or heavy drinkers. And what they're finding is that people who are drinking even up to the moderate level were actually doing better than the people who weren't drinking at all. And so that was where that concept that drinking is good for your health came from. And so people talk about this like J-shaped curve, meaning that moderate drinkers actually have lower risks of health problems. And then it's really only when you start drinking very high levels that you start having more risk of health problems than people who don't drink at all. What they realize was wrong with that is that in the people who don't drink at all, many of those people are not drinking because they're actually really unhealthy for another reason. Like, they might have heart failure and they like don't want to drink because they don't want it to mix with their medication. Or they might have had a history of alcohol use disorder and they're actually in recovery. So they've already had some damage from alcohol and they are not drinking because of that.

• 2:08Speaker 01

  And so when you change the reference group, you actually make the the sort of group that you compare people to to people who very rarely drink. So it's not that they're not drinkers at all, but they drink, you know, very, very light levels. Then you start to see that those like health benefits of alcohol go away, especially if you look across all conditions.

• 2:26Steven Bartlett?

  Are you telling me that there's no healthy level of alcohol consumption?

• 2:30Speaker 01

  Yes, I would never say drinking alcohol is good for your health. That doesn't mean that drinking at what we call low risk levels can't be a part of a healthy lifestyle. So it's a slight slight shift that like, don't fool yourself into thinking that drinking that glass of wine is like going to exercise for 30 minutes. Like, it's not something that's going to promote your health. I think of it more like having dessert, eating bacon, going out in the sun. There are risks associated with all those activities. It doesn't mean that I would say you can never do any of that, but you need to understand what the risks are and then make choices for yourself.

• 3:01Steven Bartlett?

  So I look at this glass of wine here and this pint of beer.

• 3:05Speaker 01

  Yep.

• 3:06Steven Bartlett?

  If I drank one of these a day, not a huge amount, I think what people tend to think is they think, well, it's only one. So my body will just flush it out and there'll be no adverse health consequences.

• 3:18Speaker 01

  Yep.

• 3:19Steven Bartlett?

  Is that true?

• 3:21Speaker 01

  Well, so part of the challenge is what we think of as one drink. So I think much like, you know, if you learn to read the serving size on a food, you realize that like, oh, a serving of ice cream is like a half scoop. It's not like a giant ice cream sundae. The same is true with alcohol. So in the UK, the kind of low risk drinking limits talk about units of alcohol, which is the equivalent of eight grams of alcohol. So how much of a drink has eight grams of alcohol? And to be in that low risk category, you have to be below 14 units. The problem is that glass of wine, just eyeballing it, has several units of alcohol. So it is not a, even though we think of it as a single drink, it's probably, I mean, I have to guess, but it's probably like three units of alcohol.

• 4:02Steven Bartlett?

  So if I have a glass of wine every day, I'll be over that limit then?

• 4:06Speaker 01

  You'd be right at that limit. The problem is, most people don't drink just one glass. If you, you know, you have two glasses one day and then one glass one day and then three glasses one day because you're at a social function, all of a sudden, you're actually quite a lot over that limit.

• 4:19Steven Bartlett?

  So if you said that this is roughly three units, roughly?

• 4:22Speaker 01

  And you get 14 a week.

• 4:24Steven Bartlett?

  You get 14 a week?

• 4:25Speaker 01

  Mm hmm.

• 4:25Steven Bartlett?

  So three times seven?

• 4:26Speaker 01

  Mm hmm.

• 4:27Steven Bartlett?

  Twenty one.

• 4:27Speaker 01

  Yep. So yes, you're over if you're drinking that size. Yep.

• 4:31Steven Bartlett?

  Okay, so if I have this glass of wine every day, then I'd be over the UK limit of?

• 4:37Speaker 01

  Lower risk drinking.

• 4:38Steven Bartlett?

  Lower risk drinking. So I'd be medium risk drinking.

• 4:40Speaker 01

  You'd be in what we call moderate risk, which is associated with pretty much every form of cancer, which I think people don't know.

• 4:48Steven Bartlett?

  Okay, because I was wondering why cancer has been increasing.

• 4:53Speaker 01

  Yes.

• 4:53Steven Bartlett?

  A variety of different forms of cancer have been increasing. You know, breast cancer is one of the ones we always hear about that's increasing. So you're saying, what is the data in terms of low or moderate risk of drinking and cancer?

• 5:06Speaker 01

  Yeah. So the data is growing and really worrisome. So for breast cancer, so there's really, there's a few cancers that even at low risk limits, you see the risk begin to increase. So where we would say there's kind of no healthy, or there's no even like low risk amount. So breast and esophageal cancer are two examples of that. So breast cancer, if you were to drink below those low risk limits, so in the US, that would be fewer than seven drinks, but a drink in the US is five ounces of wine, which is smaller than that. Or in the UK is below that 14 units. So it would be, you know, fewer than seven of that, that size glass of wine. We still see a slight increase in the risk of breast cancer. It's about a 5% increase. So that means your risk of breast cancer would increase by about 5%. And that's not huge. So I think, you know, percent increase is kind of hard

• 5:51Speaker 01

  to do the math on. But if you think in the US, for example, the average woman has a 13% likelihood of getting breast cancer in their lifespan.

• 5:58Steven Bartlett?

  13% likelihood?

• 6:00Speaker 01

  Really, yeah.

• 6:01Steven Bartlett?

  Wow.

• 6:01Speaker 01

  Really high. So 5% increase would increase that to like 13.6 or so.

• 6:06Steven Bartlett?

  So that means that if there's nine women in this room?

• 6:10Speaker 01

  Yeah.

• 6:11Steven Bartlett?

  One of them has, is going to get breast cancer probabilistically?

• 6:14Speaker 01

  In their life. Yep.

• 6:17Steven Bartlett?

  Damn.

• 6:17Speaker 01

  Yeah.

• 6:18Steven Bartlett?

  Why is it, and it's increasing?

• 6:20Speaker 01

  Yeah, and so the reasons for that are likely environmental because your genes don't change over that time period. So the risk factors, you know, if you think about breast cancer, it's alcohol, it's obesity, it's, you know, age when you have children or don't have children because it's a really hormonally driven cancer. Same thing if you think about colon cancer. That's a really scary one where we're seeing more and more cases in younger people. Some of the drivers of that, eating meat. So processed meats increase your risk of colon cancer. So, you know, these very sort of normal behaviors. There's probably other environmental things, honestly, that we're not yet measuring or able to measure, just given the rate of acceleration. When I talk to my colleagues who are oncologists, you know, things like plastics or other things that we don't yet know, there's, it's clearly something in the environment that is driving

• 7:05Speaker 01

  these increased cancer risks.

• 7:07Steven Bartlett?

  So even at, even at this sort of level, if I'm drinking, that might be one unit, right?

• 7:12Speaker 01

  Yes. So that would be one unit. So that would be fewer than 14 of that. So you could see like, you know, if you had double that, it would be a decent pour of wine. You could not have more than seven of those in a week to be in low risk. But even drinking that amount, your risk of breast cancer would go up a little bit.

• 7:27Steven Bartlett?

  Even this amount?

• 7:28Speaker 01

  Mm hmm. There's really sort of no safe amount of alcohol when, when it comes to breast cancer.

• 7:34Steven Bartlett?

  Is it just breast cancer?

• 7:36Speaker 01

  So that low risk category, so when we, these big cancer studies categorize people as sort of low risk or light drinkers, moderate or heavy. And for pretty much every cancer, once you get to the moderate category, we start seeing increases. And there's what we call a dose response relationship. So the more you drank, the higher your risk of cancer. There's only a few cancers that the risk seems to increase even at that very low level, and breast cancer is one of those. And then esophageal cancer is one of those. So there are certain cancers where even a small amount of alcohol will increase your risk.

• 8:07Steven Bartlett?

  Does it have an impact on thinking about cancers that are prominent in men?

• 8:10Speaker 01

  Yeah. So colon cancer, we're seeing that in a lot of young men. Liver cancer, yeah. Prostate cancer, which is obviously a male cancer, we don't think of as much as being sort of an alcohol sensitive cancer, but most cancers, because the way alcohol impacts your risk of cancer is not really on a specific organ outside of the liver. It's really about how it changes our DNA. So it's about inflammation and what are called reactive oxygen species that sort of change our cells and increase the risk over time of the mutations that lead to cancer.

• 8:41Steven Bartlett?

  So yeah, can you drill down on that? So if I'm a heavy drinker, so say that I'm drinking, let's say I'm drinking two glasses of wine a day consistently, which I guess would, like if I was drinking-

• 8:51Speaker 01

  If you're drinking two of those glasses, yeah, you'd be in the heavy category.

• 8:54Steven Bartlett?

  So two of those a day puts me in the heavy drinker category.

• 8:56Speaker 01

  Which would surprise most people, right? Like that, for many people, is very normal.

• 9:02Steven Bartlett?

  It is very normal, yeah. I think it's somewhat more difficult for younger people to understand because younger people drink less. But if I think about the generation above me, having two glasses of wine a day is quite normal, after work, on the weekends, with every meal that you have. So that would make me a heavy drinker. And then what are the stats saying in terms of my cancer risk profile?

• 9:25Speaker 01

  Yeah, so it varies by cancer, but roughly we're talking like a 40% increase in cancer, depending on the cancer type. And the more you drink, the more that's going to go up. So, you know, these are scientific studies where it's not precise to you as an individual. They're based on large populations, but definitely the more you drink, the greater the risk.

• 9:42Steven Bartlett?

  And then if I have other sort of, do they call them comorbid disease?

• 9:45Speaker 01

  Yeah, exactly.

• 9:46Steven Bartlett?

  So other illnesses, other diseases in my body, my probability is going to go further from obese, if I'm overweight.

• 9:52Speaker 01

  Exactly, if you smoke. So one of the main drivers of alcohol too and cancer is that it actually makes you more susceptible to the cancer-causing effects of tobacco. So if you drink and smoke, your risk of cancer is going to be even higher.

• 10:05Steven Bartlett?

  How does that work?

• 10:07Speaker 01

  The thought is like, if you take esophageal cancer at like the cellular level, it makes you more susceptible of the carcinogens, which are kind of the cancer-causing compounds in tobacco. And so rather than just saying like an additive risk, you actually almost get a multiplied risk in terms of the risk of cancer. So smoking and then obesity is the other big one. So a lot of cancers, your risk goes up if you're, if you're, you know, have an increase in your body mass.

• 10:30Steven Bartlett?

  What's going on in the body then? If I drink alcohol, how is that leading to cancer? You referenced it slightly there, but I'm trying to, I want to make sure I'm super clear in my brain as to like what the, the knock-on effects are and how that ends up as cancer.

• 10:43Speaker 01

  Yeah, I mean, there's lots of different mechanisms. So I mean, maybe starting just with like, what does alcohol do in your body? So you ingest alcohol, the like fancy name for that is ethanol. It's a molecule and it basically gets absorbed pretty quickly from your stomach. And so, you know, it hits your bloodstream usually within 10 minutes or so of having a drink. How much it hits your bloodstream depends on how much water you have in your body. So alcohol doesn't penetrate into your fat. It just kind of diffuses into the water parts of your body. So that's actually why for many women, they will get more sort of drunk or more of an effect from alcohol at a lower level than men, because women have more body fat than men. But that's going to depend on you as an individual. If you have more body fat, you're going to have a different impact. So alcohol gets in your bloodstream. Alcohol can instantly cross across what we call your blood-brain barrier. So it impacts your brain instantly.

• 11:27Speaker 01

  And that's where you feel the initially pleasurable effects for many people of feeling a little relaxed, feeling more social, feeling a little bit, you know, less anxiety. If you keep drinking and that level keeps going up, then you start having impaired judgment. You might have motor, lack of motor coordination. So we've all seen this and many people have probably experienced it. You know, you may be stumbling, not able to drive safely. You're not going to make the same decisions you would make if you weren't drinking. And then if you keep drinking, then you get, you can actually lose consciousness of pass out and people have experienced that. Your body is going to try to break down alcohol as quickly as it's able to. Like anything, we want to kind of excrete any abnormality and get back to our normal functioning. And so that process happens mostly in your liver, which is why the liver is so sensitive to alcohol.

• 12:10Steven Bartlett?

  Because your body sees ethanol as poison.

• 12:13Speaker 01

  Yes, I mean, you know, I know you talked about this Dr. Lemke, but your body always wants to restore what's called homeostasis. You're always, your body's always going to fight to get back to what it feels its normal is. And so ethanol is not something that belongs in your bloodstream. Your body's going to try to excrete it as fast as it can. And then it converts it into something called acetate, and then you can pee that out and breathe that out and get rid of it. So to eliminate the alcohol in your body, you have to go through this process. And part of that process includes this toxic molecule that's going to be floating around and causing damage to your cells. So that's one way that alcohol can cause cancer. The other is just general sort of inflammation. People have probably heard that inflammation is just not good for the body and increases the risk of cancer.

• 12:54Speaker 01

  And alcohol generates a lot of that inflammation in the process of getting eliminated. And so it can actually change your cells that over time that can lead to cancer.

• 13:03Steven Bartlett?

  So I also found this graph, which shows, for anyone that can't see what we're describing at the moment, it shows the acceleration in liver disease, death rates and general liver disease compared to other parts of the body. Other organs in the body, I believe it shows. What impact does alcohol have on the liver? And we have our little mannequin here of the human body. Where is the liver?

• 13:24Speaker 01

  Yeah, great question. So here's our little mannequin. So just to orient people to the body, so we're looking at the inside of the body. So like the ribs are gone, the outside of the skin is gone. These two pink things are the lungs. They kind of encase the heart. You can see the heart's behind the lungs pumping your blood. The liver is this brownish organ. It's on the right side of your body, right under your ribs. It's quite large.

• 13:45Steven Bartlett?

  It's big.

• 13:46Speaker 01

  An amazing organ. It is quite big. It processes much of what, any kind of toxins that we take in, things that we eat, your glucose, alcohol. 90% of it's metabolized by the liver. So the liver is sort of the clearinghouse, getting rid of byproducts in your body. The other are the kidneys, but the liver plays a huge role, especially in alcohol. So it sits right here.

• 14:08Steven Bartlett?

  It almost looks like it's as big as the lung, as one lung.

• 14:11Speaker 01

  Yeah, yeah, it is.

• 14:12Steven Bartlett?

  Really?

• 14:13Speaker 01

  Yeah, it's a giant organ. And it's an amazing organ. So you could actually cut out 80% of the liver and it would regrow itself. So kind of like, you know, those lizards that you cut off their tail and they regenerate a tail. The liver is fascinating. It's why we can do living liver transplant. So I could take half of your liver and give it to someone who needed a liver. You would still be able to live and they would get a second chance at life from that part of your liver. So it's this really cool organ that can regenerate. But it can only regenerate up to a point. So once you get to a level where you have a lot of scar tissue in your liver, we call that cirrhosis. You sort of reach a point of no return where at that point the liver can't heal itself. So I sort of think of it like, to use a baking analogy, if you're making muffins or a cake, you're going along,

• 14:57Speaker 01

  you're mixing all your ingredients and you realize, before you put things in the oven, like, oh, I forgot the eggs. You can still add the eggs in and like whisk it all together and it's going to be okay. If the muffins are baking in the oven and you forgot the eggs, you can't like pour the eggs on top and make the batter the same. And the liver's sort of like that, that up to a certain degree, you can actually completely repair the effects of things like alcohol or obesity, other things. But once you pass that point into scar tissue, the liver can't regenerate anymore. And so when you think about that graph or just the rising rates of liver disease, the main drivers of liver disease are obesity and two is alcohol. And so those are the leading causes of liver transplant. And the thing that is, you know, so sad is, I mean, I see this all the time working in the hospital

• 15:42Speaker 01

  is, first of all, we're seeing younger and younger people coming in and liver failure. So people in their twenties coming in and fulminant liver failure from alcohol and then dying in the hospital. And the terrible thing is that they often didn't even know that this was causing a problem in their health. And by the time they get to the hospital, they're so sick, it's too late. And yet, all of that could have been prevented or even repaired if it was caught sooner. And so that's where I think this education of understanding, like what really are the health harms of alcohol and that we have normalized binge drinking in many occasions, especially in young people, as being totally normal and yet there are very serious health consequences.

• 16:18Steven Bartlett?

  So I've got a bunch of questions around the liver.

• 16:22Steven Bartlett?

  Does that mean that my liver can take a bit of a beating before there's any real problems? Should I, you know, someone like me, I don't drink alcohol. I'm not engaging in anything too bad, but sometimes I do wonder if I could have like a blowout weekend and then my liver would just recover to normal again and I'd be fine.

• 16:38Speaker 01

  Yeah, I mean, so first, every person is different. One blowout weekend, you probably would be fine. Anyone would probably be fine. The challenge is one blowout weekend then leads to like multiple blowout weekends. And then over time, that can actually accelerate the damage to your liver.

• 16:52Steven Bartlett?

  You said that my liver regenerates though, so I'm thinking this thing will just pop back to normal again.

• 16:56Speaker 01

  As long as you haven't gotten to that scarring phase. So once you get too far down that path, even if you were to stop drinking, your liver won't recover. The hard thing is that that we don't totally understand who and why that happens so young too. So this is an active area of investigation because there are people who've been drinking for 60 years and their livers don't show signs of scarring. And then we're seeing these young people at 25 who come in and die in the hospital. And so there are individual factors that you don't have any way of knowing that are going to impact your risk of developing liver inflammation and scar tissue. And so the safest way to prevent that is to not drink in these really highways that we know are going to lead to harm. The other way is to get medical care because often we do detect these things through blood tests and we can do ultrasounds.

• 17:39Speaker 01

  And when we see those early phases, so what happens first is you actually get fat deposition in your liver. That's the first step. And then we see inflammation in fatty liver. And if you don't stop the thing that's driving those changes, over time, we see the development of what's called fibrosis, which is like scar tissue. And then that scar tissue gets more and more advanced to the point that your liver stops functioning and you either die or you need a liver transplant.

• 18:02Steven Bartlett?

  What activities outside of alcohol cause great stress on our liver that we might not see as obvious?

• 18:09Speaker 01

  Yeah, so obesity.

• 18:11Steven Bartlett?

  Food does.

• 18:12Speaker 01

  Yeah, food. So your liver is very involved in glucose metabolism. So our diet and our body weight impact our liver health. The other medication, so acetaminophen or Tylenol, which is a very common over the counter pain reliever, above a certain threshold can cause serious liver damage. So sometimes we'll see cases where someone didn't realize that like their cold medicine plus the Tylenol they were taking, both had that ingredient and then they go out and drink heavily and that kind of combination effect can cause liver damage.

• 18:44Steven Bartlett?

  Do you think, this might be a bit of a strange, a bit of an unclear question, but how much alcohol is going to cause liver damage?

• 18:52Speaker 01

  So again, it varies person to person. For liver damage, it does tend to be the moderate to higher amounts that cause damage. One thing is that, you know, that having these big surges, like these massive binge episodes, is probably more harmful than drinking like at a moderate level for a long period of time. Those like big surges cause a big buildup of that toxic byproduct that your body has to clear. And so, you know, if you have several years of binge drinking heavily, that actually probably is going to cause more damage than a longer period of time of just drinking above the risk limits. So really trying to minimize and avoid those very heavy drinking episodes is incredibly important. And then keeping it to those low risk guidelines, which we just learned are kind of eye opening and how low risk they are is going to reduce the risk of liver damage.

• 19:38Steven Bartlett?

  And does alcohol just impact the liver?

• 19:40Speaker 01

  No, I mean, alcohol has effects across our body. So many parts of the body can be affected by alcohol. So kind of starting from the top, your brain. And we can look at this with pictures, like an MRI.

• 19:51Steven Bartlett?

  Oh, I've got one next to me.

• 19:52Speaker 01

  Yeah, I think.

• 19:53Steven Bartlett?

  This is, by the way, shocking.

• 19:55Speaker 01

  Yes. So when we do an MRI of someone's brain, we basically, this is like a cross slice. So it's almost like you're, you're facing me and I'm cutting your face off and looking at your brain onwards. Healthy brain tissue is the gray and white matter and you want it to be as plump and like taking up as much space as possible because that's where all of your brain activity is. When people get really old or have dementia, one thing we see is more and more of the black space is essentially water. So we see the brain starts shrinking and shrinking and there's more water and less active healthy brain tissue. That process is accelerated with heavy alcohol use. And so you can see here, this is a 43 year old person with severe alcohol use disorder where their brain looks the way, you know, a 90 year old with dementia would look because of that brain

• 20:38Speaker 01

  damage over time from alcohol use. And so we can actually, a form of dementia is related to alcohol use. And so your brain can be hugely impacted with alcohol.

• 20:47Steven Bartlett?

  What is going on there? Like, what's causing the brain to deteriorate in such a way because of alcohol?

• 20:52Speaker 01

  Yeah, well, I remember I said ethanol, which is the molecule, crosses the blood-brain barrier. And so, especially when you're having these high levels of blood alcohol, that ethanol is sort of bathing your brain. And if you think about what we talked about, inflammation and changes to cells and to DNA and proteins that is happening at the brain level. The other thing that can cause, accelerate the brain damage we see with alcohol is actually nutritional deficiencies. So people may be drinking a lot and they're actually not getting really crucial nutrients in their diet. And that can accelerate the process of brain damage. We can even see a very, like, sudden onset amnesia from heavy alcohol use in the, in the setting of not getting enough nutrients in your diet.

• 21:33Steven Bartlett?

  Okay, so that's the brain.

• 21:34Speaker 01

  That's the brain. So the brain, for sure. The next is the mouth and your esophagus. So obviously, you're drinking alcohol, it's bathing your mouth, it's bathing your esophagus and your stomach. So we do see an increase in cancer, like we talked about, and that's accelerated by smoking. But we also see, like, benign but annoying and problematic health conditions, most notably acid reflux, so heartburn. So if you notice, like, oh, I'm, like, always having heartburn, I'm having to pop all these, like, antacids and take this medicine, you might want to think, like, how much am I drinking? Is that contributing to my heartburn? So that's a very common thing. The heart is affected by alcohol. So, you know, the heart is an organ where at low-risk levels, there doesn't seem to be harm from alcohol, but once you get into the moderate and high, we see harms. And the harms can be a couple-fold.

• 22:18Speaker 01

  One is something called atrial fibrillation, which is basically where your heart starts beating really irregularly.

• 22:24Steven Bartlett?

  Yeah.

• 22:24Speaker 01

  So, in your heart, there's four chambers. The two chambers at the top, so this is really showing the ventricles and the atrium. So there's two chambers that blood flows through. And in a normal heart, your electrical activity comes from the top of your heart, goes down to the bottom of your heart, and tells the heart to pump. And so you get a single impulse that goes to the bottom of the heart, says pump, and that pumps blood out to your brain and your body and your organs and your liver. In atrial fibrillation, the top of the heart is just kind of quivering with this abnormal electrical activity, and so the heart can't pump in a normal way. We actually, there's a term in medicine called holiday heart, because we see sometimes people drink a ton over the holidays and will end up in this abnormal rhythm just from that binge drinking pattern. And then over time, if you're drinking at high levels, your heart actually dilates

• 23:07Speaker 01

  and you can end up with congestive heart failure from a cardiomyopathy, which means the heart muscle gets kind of weak and thin and floppy and can't pump the way that it needs to.

• 23:18Steven Bartlett?

  What you just listened to was a most replayed moment from a previous episode. If you want to listen to that full episode, I've linked it down below. Check the description. Thank you.