Best Behaviour: Neuroscience and Health
This month we’re lifting the lid on health-related behaviour at the UK's Academy of Medical Sciences and USA's National Academy of Medicine's Rosenthal Symposium on health behaviours. We're asking what neuroscience can tell us about why we tend to overdo it on the cake, despite knowing we shouldn’t, and looking at how understanding behaviour can help us change it for the healthier. Plus, we’ll discover what’s hot off the neuroscience newsreel with the help of some local experts.
In this episode
01:08 - Distracting car passengers
Distracting car passengers
with Duncan Astle, Cambridge University; Helen Keyes, Anglia Ruskin University
Joining Katie Haylor to cast their eyes over the latest neuroscience papers were cognitive neuroscientist Duncan Astle from Cambridge University and perceptual psychologist Helen Keyes from Anglia Ruskin University. First up, Helen came across news of research that could put a few passengers in a spin!
Helen - They wanted to address the idea that we know that in-car conversations are less distracting than conversations that happened, for example, on the phone for drivers, probably because passengers tend to modulate their conversation. So if a risky driving scenario arises a passenger will generally be quiet and stop the conversation, so they wanted to address this: would experienced passengers modulate their conversation more than a novice passenger? So a novice passenger might be aware of the driving danger that's happening.
Katie - So is this along the lines of if you are an experienced driver you can appreciate that roundabouts take, for example, quite a lot of concentration, so I'm going to hush up, be quiet and let them get on with it?
Helen - Absolutely, we call it situational awareness and we're wondering whether the passenger situational awareness would help the driver to also increase their situational awareness and not get distracted.
Katie - OK, so how did they study this then?
Helen - So they had forty, two person driving teams in a lab on a driving simulator and the teams would be watching driving scenarios that would include some hazards, and they were chatting. What was really happening was that they were having a word association task game, where the passenger would say a word such as yellow and the driver would say an associated word such as lemon, and then they would measure two things. They'd measure conversational modulation, in other words the length of time between the words. A bigger gap would mean you're taking into account the driving scene, and they also measured your situational awareness following each clip. So you'd be asked questions such as what color was the car behind you? Did you notice any traffic signals? Things like that to see what the drivers awareness was of the situation.
Katie - So, what did they find out?
Helen - They found that having a novice passenger led to less conversation modulation. In other words, novice passengers didn't stop talking when a dangerous situation arose, and interestingly having a novice passenger significantly reduced the drivers situational awareness. There wasn't any conversational modulation, therefore novice passengers are very distracting and therefore the driver situational awareness was worse.
Katie - This sounds quite significant, certainly not something that I had really appreciated before. How common is this knowledge?
Helen - We know that for example, when you're a learner driver you're only allowed to have somebody in the car with you that is an experienced driver with more than three years. So there is some awareness of this, and we are thinking about bringing in graduated drivers licenses. In fact, they are almost certainly going to come into the UK and they're already in existence in other countries and a graduated driver's license you would have for maybe two years after you pass your test. It might do things like limit the number of passengers in your car, restrict the hours that you are allowed to travel at, and the speeds you are allowed to go at. But studies like this are kind of showing that maybe we should have more of a focus on passenger experience, not just number of passengers.
Katie - And what about age? What about kids, for instance, screaming in the back of the car. Surely that's distracting for drivers?
Helen - Yes it's a big frustration. A kid screaming in the background is one of the most distracting effects you can have, particularly if they are your own children. So in this study when we're talking about novice or young people being quite distracting, we tend to be talking about young adults. But there's a whole separate category for children that's definitely distracting influence, which is going to be quite tricky to make laws about how distracting your own children are.
Katie - Okay. So bottom line, what should someone take away from this study?
Helen - If I were a novice driver and I'd just learned to drive, just passed my driving test, I think I would have a stern word with anybody I was going to be sharing a driving situation with as a passenger to either not speak with me, which is a good idea, or else I'd be aware myself not to have some novice passengers in the car with me.
Katie - Wow, so I can legitimately tell my friends to shut-up because I just passed my driving test?
Helen - You have my blessing, yes.
Katie - Duncan, do you have any thoughts or comments you'd like to add?
Duncan - It’s very interesting because it implies that even when we're not driving but we're just in the car, on some kind of almost subconscious or implicit level, we're appraising the situation and moderating our conversation, our behaviour accordingly. And that to me is very interesting, because as someone who drives a lot but also as a passenger quite a lot in the car, I'm totally unaware. But, on some level I must be doing it, right? If I'm an expert driver and I'm moderating my conversation.
Helen - I love that you describe yourself as an expert driver! Congratulations, but secondly yes, expert driver, I'm sure you are modulating your conversation. Absolutely, and the fact that you're not aware of it means you probably are an expert driver, but you're just doing it subconsciously.
Next up, Duncan Astle took Katie Haylor through a paper that's rather close to home!
Duncan - So this is slightly self-indulgent as this is one of our own papers. How do we study the human brain? And one of the main ways is we take a cognitive skill or behavior that we're interested in and we group everybody together that has that cognitive skill or cognitive impairment or behavior, and then we compare them to a control group and we put both groups in the brain scanner and whatever difference we find is the neural correlate or the brain correlate at that particular aspect of behavior, and almost everything we know about brain behavior relationships in human beings is derived using that kind of logic.
But there's a really important problem with it. Even though we've grouped people according to our behavior or cognitive skills, it doesn't mean that has arisen for the same reason in every individual in that group. There might be multiple different pathways that lead toward that particular behavior and by putting them all together in one big group, we're actually really muddying the waters and maybe not really getting to the underlying root cause of why that behavior might occur in the first place and so that's the problem that we were trying to address.
Katie - So you’ve turned brain science on its head then?
Duncan - In a way. Yes we use three large samples of individuals, one from New York, two from here in Cambridge, and rather than trying to group them using cognition or behavior we put the brain data itself into a machine learning algorithm. So, just like the country's road network is organized around some really big motorways, there are some really big pathways in the brain. They're made of white matter and they are really designed for the smooth, efficient transfer of information over really quite large distances within the brain and so we extracted information about the quality of those pathways in all of our subjects and we submitted those to a machine learning algorithm. What it was trying to do was to see whether it could group individuals because they have very similar brains to one another, those tracks or those motorways, and that they're different from people in another group rather than grouping according to cognition or behavior.
Katie - OK, so how successful was it? What did you find?
Duncan - And so we found that we could group them. One of the interesting things we found was that there was one particular set of pathways called the cingulum, right at the front of the brain, part of the brain called the cingulate cortex, all the way to the back and then around and underneath, and these tracts seem to be really important for determining which group subjects went into. We then had some functional brain imaging data looking at brain metabolism and we found that actually the areas that this tract connects were also different across the groups, and then we looked at the cognitive skills and we found that they were also really very very different. So grouping on the basis of subject’s brains unlocked a way of looking at behavior that we otherwise wouldn't have learnt about.
Katie - Is this study one that's more for the scientists?
Duncan - Well I think it's for anyone who's interested in the brain and how the brain, our brains, might relate to our behaviour. So the way that we traditionally think about it is that we, let's say, we group everyone that has long term memory problems and then we think - “what's the brain cause of that”? But actually, maybe there are multiple different brain causes that can give rise to a problem with long term memory. it's very hard for us to know that unless we start to group people by the underlying brain physiology, and this paper is important I think because it's the first demonstration that that can be done.
10:45 - Apple, or chocolate cake?
Apple, or chocolate cake?
with Todd Hare, University of Zurich
How does the brain make decisions about what to eat? And how does stress influence this decision? Katie Haylor spoke with neuroeconomist Todd Hare from the University of Zurich, to find out.
Todd - So that will mean different things to different neuroscientists. My primary behaviour of interest is decisions and one thing, just to give an example, a lot of my work focuses on how people decide what to eat. So the behaviour is - I'm going to eat the apple and not the chocolate cake, or maybe I am going to eat the chocolate cake, but that's what I'm interested in.
Katie - Tell me a bit about your research and the kind of studies that you do.
Todd - Dietary choices are a big part of what we do. So we generally set it up such that people are coming into our experiments hungry. That means motivated to get some food, and we give them different options. Apple and chocolate cake is an example I just gave, but we give them hundreds of different combinations of junk food and healthy food. Sometimes they're choosing between two healthy foods, sometimes between two junk foods, sometimes between a junk food and a healthy food. While they're doing this, we are looking at the levels of activity, brain activity, loosely defined using functional magnetic resonance imaging devices.
Katie - Okay, so this is looking at the brain while it is actively engaged in doing something and using proxy markers to indicate which bits of the brain are busy and which bits are not?
Todd - Exactly right. So one of the projects we just recently finished up is looking at how stress will change the way that people make decisions about these different food items. So we brought people into the lab. Half of them we randomly assigned to go through a psychosocial stressor. That meant that they had to stick their hand in an ice cold bucket of water and one of our experimenters is there observing them judging how well they're doing this the whole time. That's the social part of the stressor.
Katie - That sounds hideous. So you've got a physical sensation that's not very nice and you feel like you're being judged by somebody. That sounds hideous. Why would you do this?
Todd - It works very well. It creates stress, sort of along the same levels of having a fight with your spouse or your boss, being late to an important meeting. We get to about that level of stress, so things that occur on a regular basis in daily life.
Katie - OK, so what does that kind of, I guess, kind of chronic lowish level stress do to our decisions to eat a cake or the apple for instance?
Todd - We don't know about the chronic, just to be clear, because we do this one time. It may be that this adds up over time, we just can't answer that with this experiment. But what we see in the acute level is that you seem to shift more toward the immediate benefits and those are the taste of the food items. So I'm much more likely to eat the chocolate cake in that case if I've been through this stress protocol than the apple.
Katie - Is that because it tastes better or is that because it's got way more sugar and fat in it that I can use to run away from my virtual Lion?
Todd - That's a very good question. In this case we don't know for sure. It would make sense that given that you're in a situation you might need to escape from when you're being stressed, you would focus more on things like energy that could help you do that, but we can't definitively establish that with this experiment.
Katie - OK. So what do you think is going on then in the body to encourage us, potentially when we're stressed, to reach for that piece of cake, which I've got to be honest, I've been there. I'm sure everyone has.
Todd - We actually see that there are two different pathways that seem to be influenced following this stress protocol. One of them is most closely associated with the physiological reaction. So we measure this with cortisol, something your body produces whenever you're stressed. There we see that if your cortisol level is higher, there are more interactions between a region of the brain known as the amygdala, which is in a region that has a lot of cortisol receptors. This seems to have a stronger interaction with regions that are involved in making the choice. The amygdala is also something that is reflecting the tastiness of these foods. So it could be that taste is having a stronger impact on choices via the cortisol effect on the connectivity between these regions.
Katie - But taste is subjective, right? I might think that an apple is really tasty and you might think it's horrible.
Todd - So that's a very important part of the experiment. We ask each individual person how tasty they think the different foods are. So I get your rating for how good an apple is, I get your rating for how good broccoli is, I get your rating for how much you like ice cream. All these things, so I know exactly your subjective opinion of taste.
Katie - OK. So I'm kind of my own control in a way.
Todd - So what we've shown is that stress makes you, stress makes it harder for you to overcome taste temptations.
Katie - If we know this about stress, can we apply it in some way to help people change the behaviours that are sometimes quite ingrained and sometimes really difficult to change?
Todd - One possibility is that stress sort of pushes you toward a default pattern of behavior. Your stress, you want to allocate resources in your brain to avoiding the stress or overcoming the stress. So you fall back on a pattern of behavior or choices that you generally make. If before you're stressed you've established a pattern of making healthy choices in the domain of food, this would be one way to use stress or be resilient to stress if your stress causes your default to be a healthy choice in the first place.
17:51 - Pick a pint glass
Pick a pint glass
with Marcus Munafo, University of Bristol
Drinking excessively and smoking cigarettes are major health problems. But can the physical environment around booze and cigarettes impact our behaviour? Katie Haylor spoke with University of Bristol psychologist Marcus Munafo, who's been looking into this. Firstly, Katie wanted to know what goes on in the brain when someone decides to have a 2nd, or maybe 3rd, drink...
Marcus - Well there are a lot of things going on. There are different influences coming from different places. There's the environment that you're in, for example. You're in a social context, you are presented with lots of different cues that might encourage you to have a drink, for example. But then when you have a drink the drug, the alcohol, is having an effect on your brain itself and the disinhibiting effect of alcohol might mean that even if you intended to only have one or two drinks you end up having three, four or five. So you've got this set of competing influences that are acting on different parts of the brain, on the reward centers, on mechanisms that manage to control those impulsive behaviors, and that complicated interplay of effects on different brain regions is difficult to understand, but really important if we want to get a handle on how and why people drink
Katie - Is it a pretty similar picture, if I was to come out of the pub, step outside, and have a cigarette, for instance?
Marcus - Different drugs have different effects. Some of the effects are common to different drugs, some of them are unique to specific drugs. But generally speaking you have this same issue of a range of different influences working in different ways on different parts of the brain, and there are some similarities between different types of drug but there are also some differences as well. So we do need to look at each one individually.
Katie - How are you using neuroscience to understand our behavior around things like smoking and drinking, habits we may want to change?
Marcus - Most neuroscientists tend to start with the brain and understand how the brain works and therefore how that might influence how we use different drugs, for example. Our approach is slightly different, in that we start with cues in the environment that we have reason to believe might be influencing our behavior, and then use human laboratory studies to try and understand how that works. There's been a lot of work done on branding on cigarette packs and how that captures the attention of people who are looking at those cigarette packs. There's also been work done on the design of glasses that you serve beer in and how that might influence drinking behavior. So we're trying to understand what it is about the features of cigarette packs and glasses and so on that influence behavior through those cognitive mechanisms in the brain, to then be able to reverse engineer that knowledge and change people's behavior in a healthier direction by targeting those features.
Katie - Let's hone in on the glasses, then. What is it about different types of drinking glasses that might make us more or less likely to drink?
Marcus - Well, if you go into a bar now you'll see that certainly if you order a pint of lager there'll be an array of different glasses that that drink will be served in depending on exactly what drink you order.
Katie - Sure. So, you've got your standard pint glass which actually isn't straight, is it? It kind of comes out a little bit at the top. You've got the really fancy Belgian beer glasses, a whole array.
Marcus - That's right. So they're shaped so that most glasses are curved. They will often, certainly if they're being used to serve lager, will have a nuclear nation stamp on the inside, which is texture on the inside of the glass that promotes bubble formation that keeps it fizzy, that keeps the head on your lager, and so on. There's branding typically on the glass, so depending on which brand of beer you're drinking you'll be served that beer in that specific glass, and all of those things have been introduced for a reason, or might have been introduced for a reason. So, understanding what impact they have on how fast you drink, or whether or not you'd like the taste of the drink, is important if we want to then be able to decide which of those features we might want to modify to promote healthier behavior.
Katie - And is there evidence to suggest that those kinds of aspects of the glass really do make a difference on someone's drinking behavior?
Marcus - Well, there is some evidence. It's still quite early days, but we ran one laboratory study where we brought people in and we randomised them to drink from either a curved glass or a straight glass. One of the things that we did was look at how people judge the halfway point on different shaped glasses using psycho-physical techniques. If you've ever had a hearing test, you have taken part in that kind of study where you have a staircase procedure, in the case of a hearing test where you have sounds that are getting louder and then getting quieter, and that going up and going down allows you to detect very precisely the point at which people can and can't hear something, and you can use a similar kind of approach when you ask people to judge where the halfway point is in a glass, for example, by presenting images that have more or less liquid in them. We found some evidence that when they were drinking lager they tended to drink faster from the curved glass than they did from the straight gl ass. The reason that we think that's happening is because when you look at the glass and try and judge how much is left in it, that's easy to do in a straight glass but much harder to do in a curved glass because the side of the glass is what your eye follows. But actually the volume changes at a different rate to what you might expect from just following the shape on the side of the glass. So in other words when you think you've got to half way in your drink you've actually drunk more like two thirds of it.
Katie - Okay, so if you're saying ‘oh no I'm going to steady myself, I'll have half a pint in half an hour’, actually it's much more difficult than that.
Marcus - Yeah, because by the time you get to where you think it's halfway actually, another couple of drinks and you finished the thing. So, that might have an influence on how fast you drink and we did find some evidence that the greater the extent to which people misjudged how much was left in the glass at the halfway point, the faster they drank. If that's the case, then it suggests ways in which we could reverse engineer that knowledge and shape behavior in a healthier way. We could either put markings on the side of the glass so that people have a clearer cue as to how much of that drink was left. Or we could encourage people to drink from straight glasses because it's easier to make that judgment in a straight glass.
Katie - So that's booze. What about smoking?
Marcus - Well, one of the things that we've been looking at in a series of studies is how branding information, and also health warning information, on packs influences where people look. We used a range of techniques but principally eye tracking. We would have people look at a screen where we presented images of different types of cigarette pack and simply tracked where they were looking and did that for nonsmokers and for smokers. Now this was interesting in the context of the legislation that was introduced a few years ago in the UK, which has required packs to be standardised so that the most prominent feature of cigarette packs now is the health warning and there's very little brand information on them.
Katie - They can be pretty graphic, can't they? Pictures of lungs that look pretty horrible. Well, I would assume, to be fair, as a non-smoker, that they would make a pretty significant impact.
Marcus - Well, there is some evidence from tobacco control research that health warnings do have an impact. Not a huge impact, but as part of a comprehensive tobacco control policy to have a part to play. But we were interested in what happened when you take away the brand information. What we found was that amongst nonsmokers, the presence of a graphic health warning meant that people's attention was captured by that, but amongst smokers they tended to actively look away from the health warning. Even when there was nothing else to look at they would rather look away from the health warning than look at that.
Katie - Wow. So, they actually go into quite a lot of effort to avoid looking at these health warnings.
Marcus - Yeah, it looks like it. It's not necessarily a conscious effort, but they were diverting their attention away from that. So when we looked into that a little bit more deeply and it seems like health warnings are actively pushing the attention of smokers away, and if they're not looking at the health warning then of course there's a limit to the extent to which that health warning can be effective. And that kind of approach can then perhaps give us some insight into how we should design these health warnings, what information we should put on them, how prominent they should be on cigarette packs, and also whether we need to combine that with other approaches like providing a direct piece of information that allows people to take actions. Rather than just saying smoking is bad for you, you could frame the message more positively by saying ‘stopping smoking is good for you, and here's a way of doing that’, with a link to some kind of support website, for example.
Katie - Can these cognitive neuroscience approaches share any insight into resilience? Because it does seem, like in the case of smoking and alcohol, the social environment plays, I would say, probably a massive part, right?
Marcus - Well, I think that's one of the areas where cognitive neuroscience really can tell us something. So, for example, I mentioned earlier the prefrontal cortex is a region that is interesting in the context of drug use, substance use and behavior generally, and that is the region of the brain involved in executive functions, these top down control functions that that inhibit our more impulsive responses, for example. Of course people are different in terms of those functions and therefore different in terms of their ability to inhibit those behaviours, so understanding those mechanisms can give us some insights into why people respond differently, because no two people are the same. Getting a handle on how and why people are different, and how that relates to behaviour, is a big part of this.
27:17 - Helping kids develop healthy habits
Helping kids develop healthy habits
with Greg Miller, Northwestern University
Could stress play an important role in children's health-related behaviours? Katie Haylor caught up with Greg Miller from Northwestern University in Chicago, who looks at how kids who come from families with fewer economic resources tend to have worse health outcomes...
Greg - We're involved in a handful of studies. Some of them are trying to understand questions about why, so, to try to pick apart the biological pathways by which growing up in a low income family, the stressors that are often associated with it, change the brain and change the body. So we bring kids in late childhood or early adolescence into our research centre, we ask them lots of questions about the stressors and the positive features in their life. So how the relationships are with their parents and with their peers, how school is going, whether they face any kind of discrimination or social exclusion or bullying. We're really interested in their day to day lived social experience.
Then, we'll draw blood from them. We'll use the blood to study their cholesterol levels and how their immune cells are functioning. We'll take their immune cells, put them into a test tube with bacteria and viruses and see how they behave. Then, on another day, we might scan their brains to look at how it's developing, what kind of structure it has, how it functions under certain tasks, and we try to put together a picture that connects their day to day social experience with how their brain is functioning and how their heart and their immune systems and their other bodily systems are functioning.
Katie - I think it's pretty well established that stress, which you mentioned just a moment ago, can affect our immune systems. Can stress affects how the brain works? Specifically in the case of kids where their brains are obviously growing?
Greg- Yes, the strongest evidence is from animal studies, but also from human studies, showing that stress does impact the brain's structure and the brain's function. This is not to say that anytime somebody has a bad day or they get into an argument with their parent, that their brain is going to be irreparably changed, but with chronic long term stress, kids can show different kinds of brain development.
Then again, we shouldn't think of this as some kind of permanent brain damage effect. The changes are subtle, consistently observed, but it isn't the case that kids who are exposed, for example, to violence in their families or in their neighbourhoods, necessarily have any kind of permanent brain damage that would preclude them from living a healthy normal life. But those kinds of experiences, if they happen on a regular basis, do lead to changes in the brain's grey matter, the volume of certain regions of the brain like the amygdala, that's involved in responding to threats, the hippocampus, involved in long term memory and regulating stress responses, and also the prefrontal cortex, which is involved in a lot of the things that make us human around regulating our own behaviour and thinking. Stress can change all of those areas, and probably more critically, the way those different regions of the brain talk to each other.
Katie - How does stress do that?
Greg - We know that stress causes fairly substantial changes in the release of hormones to the rest of the body. So, stress related changes in adrenaline, noradrenaline and cortisol, and we're all pretty familiar with the fact that those hormones do things like speed up the rate of your heart, cause your heart to contract more forcefully, so these are metabolic changes and changes in the way that many organs like the heart and the lungs function, that prepare you or allow you to fight or flee more effectively.
Well some of those hormones we also know travel to the brain and can change the way brain cells communicate with each other, there's also a whole set of hormones that are released specifically in the brain under conditions of stress that with prolonged and repeated bouts of stress, those hormones can again change communication between cells, change the structure of networks between different regions of the brain, essentially at a basic level the wiring diagram of the brain.
Katie - So, how does this relate to these everyday, really difficult problems like eating too much, drinking too much, or smoking?
Greg - So many of us recognize that when we have a lousy day, oftentimes we’ll cope with our frustration or sadness or anxiety by doing things that feel good. One of those things is often eating. Oftentimes stress promotes the kinds of unhealthy behaviours you're asking about by changing activity in parts of the brain that are involved in decision making, in seeking out rewards, seeking out pleasurable activities. There's a lot of work done in rats and some in monkeys and some in humans, that when you put it all together suggests that stress, especially these long term stresses, definitely change the way that our brain seeks out and responds to pleasurable stimuli. And also changes those decision making regions of the brain in ways that make it harder, potentially, to resist a pleasurable stimulus like a milkshake or a beer.
Katie - And so is part of the motivation for looking at how this works in kids' brains because they are obviously juvenile, so if they have chronic illnesses it's going to be affecting them for an awful long time?
Greg - Yeah. That's part of it. The other part is that the brain and a lot of the other organs in the body have a lot of plasticity in childhood and adolescence, and by plasticity I mean the capacity for change and development. A lot of the more serious health problems don't arise in childhood. They begin in childhood, but they don't manifest clinically until much later. So, the classic example of this would be heart disease, which often shows up in the form of a heart attack or a stroke when people are in their 60s or 70s or 80s, but we know from autopsy studies that heart disease itself begins often in mid to late adolescence.
Katie - If kids' brains have this plasticity in comparison to adult brains, does that mean there’s a bit more hope for interventions?
Greg - Yeah, I think many of us who are developmentalists believe that the return on investment for interventions in childhood is going to be quite high relative to other points in the lifespan. In part, it's because of the plasticity that you refer to, in part it's because any return on investment has a lot of time to compound, and it's in part because kids' health is pretty good so they're not so far down the path to overt disease that an intervention might create some kind of fork in the road, where you wouldn't have an opportunity for that much change in an older adult where, say, the underlying pathophysiology of disease, the amount of plaque, was already pretty significant.
Katie - Have you had any hints at potential interventions?
Greg - Yeah. We've had some luck working with collaborators focusing on building strong family relationships and strong communities. It's tough for kids to make substantial behaviour change on their own. Kids often don't have a lot of flexibility about what they eat, about when they engage in physical activity, a lot of those things are determined by the family they live in, the community they live in, the neighbourhood they live in, the school they go to. And also developmentally it's just hard for kids to enact the kinds of goal setting and follow through that's required for sustained behavioural change.
Working through their families and through their schools and through their communities, we can use older kids as role models and adults, sometimes parents, sometimes extended family members, sometimes teachers, as scaffolds that can help kids make these sort of sustained changes, or find different kinds of meaning in challenges they may face, in ways that help them not necessarily see the stress in their lives as permanent, not to see it as as big of a threat and to reinterpret it and cope with it in a manner that is less likely to cause health problems down the line. So, instead of going and drinking a milkshake after an argument with a friend, to go out and play basketball for an hour or release stress in other, more productive ways.
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