S2 Episode 22: The Biology of Eating Disorders


After witnessing a childhood friend suffer from a severe eating disorder, Dr. Lauren Breithaupt dedicated her career to exploring the causes of anorexia, bulimia, and related syndromes. Now a PhD in psychology at Massachusetts General Hospital, Breithaupt explains that eating disorders – once thought to be a plague of teenage girls – can affect men and women of all ages and share a genetic link with other psychiatric disorders. Plus… how dinnertime conversations help your child’s brain develop.

Seeking Help? Here are two resources:
National Eating Disorders Associationhttps://www.nationaleatingdisorders.org/
The National Center of Excellence for Eating Disorders – https://www.nceedus.org/

Phil Stieg: Hello and welcome to Dr. Lauren Breithaupt, co-director of the Eating Disorders Clinical and Research Program at the Massachusetts General Hospital. She studies the impact of restrictive eating disorders, anorexia or bulimia, focusing on mental and physical health.   Lauren, thank you for being here with us.

Lauren Breithaupt: Thank you.

Phil Stieg: So as I understand it, there’s both restrictive and excessive, least for my simple knowledge. The eating disorders. Can you define them for us?

Lauren Breithaupt: Yea, so I would say eating disorders are definitely marked by sort of either weight and or appetite dysregulation. That’s the big one. So in anorexia nervosa, the core behavior that individuals often think of would be restrictive eating versus and bulimia nervosa, you might see overeating and feeling out of control in their eating and then engaging in behaviors to compensate for all the food that they consumed, such as exercise or purging.

Phil Stieg: What are the risks to the body and to the brain from these eating disorders?

Lauren Breithaupt: There’s actually so many physical challenges that result from eating disorders. Some of the big ones are bone loss and changes to one’s bone structure, which can actually be long lasting. Changes to estrogen, which can lead to infertility problems later on. Hair loss is a big one and in fact, actually sort of growing that Peachfuzz all over one’s body actually is also commonly seen as a way to mitigate the effects of weight loss.

Phil Stieg: 
Tell me, how common is anorexia and how common is bulimia?

Lauren Breithaupt: So for anorexia, the prevalence is somewhere actually between one and four percent. It’s about similar for bulimia, if not a little bit higher, which I think is actually a really important point. So if we think of sort of all of the psychiatric disorders that we think of as severe is schizophrenia. But the prevalence of schizophrenia is actually less than one percent.

Phil Stieg: Are these eating disorders more common in boys versus girls? Is it familial?  Is there a biological predisposition?  Where do they fall?  Or are they all over the spectrum?

Lauren Breithaupt: You’ve nailed that all over the spectrum, actually. Anyone can actually develop an eating disorder regardless of race, age, nationality or sex.  We see individuals across every spectrum that you could imagine. There is this really antiquated model of eating disorder that used to focus really sort of on family dynamics or socio-cultural factors. And so that’s why we thought that it could only happen perhaps in young adolescent girls with this really specific phenotype.

Phil Stieg: In preparing for this, I got the sense that these restricted disorders are more biologic and less and less psychological or psychiatric.  One of the things I don’t want people to feel is that, you know, I’ve got some psychological problem and that’s all it is. You know, there is some biologic genetic component. Can you explain that succinctly?

Lauren Breithaupt: We do know that there is a biological and genetic component to eating disorders. It’s been established now. We do know that part of the genetic component of this seems to be both psychiatric and metabolic. So when I say it’s psychiatric, we see that eating disorders itself are genetically related to other psychiatric disorders.  We also see that then it’s metabolically related, suggesting that if an individual is at this low weight, they are able to function at this low weight or perhaps that part of their genes is sort of drawing them to stay at a low weight.  So treatment’s hard because now we’re asking them to overcome sort of their core biology. And right now our treatment that we’re using, it’s talk therapy. We’re asking someone to think about and to change different, change their behaviors and change their thoughts. But really, we’re asking them to overcome this core biology.

Phil Stieg: 
Where I see it in practice is kids that are  ADHD and so their psychiatrist puts them on Adderall and then all of a sudden, they lose their appetite.  So that to me means that there’s a strong biological component to it. And so how are you managing that problem?

Lauren Breithaupt: Exactly, right? I think what you’re saying actually speaks to the fact there is definitely a biological component to this. So you take away their appetite and then all of a sudden you see the development of an eating disorder. And what’s interesting, I think with the Adderall piece that you just mentioned, is we see different types of eating disorder developed from the same environmental change. So in some individuals, when they lose their appetite, we actually do see kids develop binge eating disorder. So they end up binging and then purging. And then for some individuals, actually, that removal of appetite or that change in appetite leads to not eating anything. We see development of anorexia.

Phil Stieg: Was there some major discovery or enlightening moment that transformed thinking that it’s a psychological to a metabolic issue?

Lauren Breithaupt: Yeah, so there’s been some really seminal work recently on the genetics of eating disorders, and it’s really focused on anorexia.  This work is actually led by one of my mentors, Dr. Cindy Bulik. And so she looked at the genomes of tens of thousands of individuals with and without anorexia and identified eight chromosome locations that may increase vulnerability to the disease. So some of these locations then were linked to a wide range of metabolic challenges. One of the most perplexing and actually really frustrating parts of that is that individuals we think, you know, we’ve re-fed the individual so that they’re back to a healthy weight and then we send them back out into the world and we see their weight just plummet again. And so this has made us think that there’s something actually in their biology that is actually causing them to stay at this low weight.

Phil Stieg: So thinking specifically since I’m most interested in the brain, what are the impacts of anorexia or bulimia specifically on the brain?

Lauren Breithaupt: So there’s a reward center in our brain itself, right, and it’s really connected with the front part of our brain that helps us make decisions, as well as more central parts such as the insula. So what we’re saying and eating disorders too is that there’s oftentimes a disruption in the reward pathway. So we’re saying that individuals, when we show them pictures of food and they have anorexia, we’re seeing a lack of activation in these reward pathways in the brain. So we’re not seeing our typical response in key centers of reward, such as the insula we would be expecting to see. On the other hand, though, in bulimia, you actually see under activation in prefrontal areas.  And we think that this could be actually because for these individuals, they’re actually relying more on impulsivity. After someone is eating,  they’re impulsively leading to a purge later on.

Phil Stieg: I hope I’m normal.  So there are days where, you know, I just devour food and then I’ll go home and I go, I’m not eating, I’m going to fast. And I, I don’t know whether it’s because I looked in the mirror and I don’t like the “little Buddha belly”.  Is that normal or what’s going on in my brain?

Lauren Breithaupt: It probably is, because the next day when you wake up, you probably don’t do the same thing over and over and over again. Or you don’t think to yourself,  hey, that really worked for me. Let me keep trying it as well. I think the other thing that distinguishes, you know, normal versus un-normal, because that’s something I hear all the time, too, is that for individuals with eating disorders, their entire life revolves around oftentimes food when they’re going to eat, when they’re not going to eat.  And so it’s completely engulfed.

Phil Stieg: 
And as I understand it, there are specific changes in brain structure as a result of these restricted disorders.  What are those?

Lauren Breithaupt: Yeah, so one of them, one that we most commonly see an eating disorder is we see an overall decrease in gray matter in our brain, which is going to be important. Right, because gray matter helps us process information. It allows – sort of holds the cells that transport nutrients and energy to our brain. So if we’re overall decreasing that gray matter, we’re going to have a harder time communicating within areas of our brain.

Phil Stieg: The excessive exercise component of this is, I found a little bit interesting, you know, people might have a normal eating pattern, but then they’re addicted to running. What is the similarity there between that excessive exercise and an eating disorder? Is that genetic? Is that biologic?

Lauren Breithaupt: So I do think that there’s probably a biological drive for individuals with eating disorders to more easily develop ingrained habits. Right. Sometimes we hear the story too –  individuals will say, you know, I started doing one thing and then I couldn’t stop. And so that excessive exercise seems to be some somewhat similar. Right in some individuals. It’s fine to go on a run, whatever you want to, and you can stop.  In fact, it feels great stopping. But for individuals with an eating disorder, the way that habits develop tends to be a little bit different, such that  individuals will switch from practicing a behavior and then an inability to stop.

Phil Stieg: So what do you tell people you know, is your gestalt, your sense of this, that, you know, moderation is good?

Lauren Breithaupt: Yeah, that is definitely my sense of this, is that, in fact, moderation is good and that these extreme levels are really challenging. . I think with exercise, you know, the part that we don’t even think about, too, especially for females, is that exercise also impacts and influences the hormonal system as well. In females who are exercising a lot or restricting their diet, we do see changes in their estrogen cycle. So basically, they don’t have enough estrogen to have a period anymore. And we know that estrogen itself is actually neuroprotective.  So estrogen actually serves by actually filtering out inflammation in our brain.

Phil Stieg: What part of having these disorders is hormonal?  Is there a hormonal change that makes you anorexic or bulimic or vice versa?

Lauren Breithaupt: With the hormone piece itself, we do actually see this interaction right, where individuals we do see these changes in hormones. What is challenging, though, is that these hormones sort of perpetuate the disorder.  So two hormones that we’ve done a lot of work on, looking at are ghrelin as well as leptin. And so these control  how hungry or full we’re going to feel. And they’re activated actually by eating.

Phil Stieg: I want to get into the ghrelin.  I was fascinated by it. I understand ghrelin is secreted by the gut.  Through the blood, it gets up into the brain, goes through the blood-brain barrier and has all these impacts. Can you explain that?

Lauren Breithaupt: Ghrelin itself, is activated actually by eating. So it’s secreted in the gut, but then we actually see ghrelin receptors in the brain itself.  What we see in anorexia is that typically more and more ghrelin is expressed when an individual is hungrier. But we don’t see that hunger response in anorexia. So we see this as “ghrelin resistance” . So individuals with anorexia, we believe, are actually developing resistance to ghrelin.  So basically, once they start eating, we do see fluctuations in ghrelin. We see tons and tons of ghrelin being released, but we see no response to hunger itself.

Phil Stieg: Now, I know you’re a scientist, not a dietician or a nutritionist, but tell me, you know, if I go eat Big Macs and too many cheeseburgers, what’s that doing to the gut and what does that do to ghrelin?

Lauren Breithaupt: Over time, if you eat more and more food, you actually should see that you actually have more and more ghrelin actually being released. So you actually might feel more hunger over time as well.

Phil Stieg: By eating more of the junk food.

Lauren Breithaupt: It’s shown to be some of the time that the more food or more junk food that you have, so a lot of time sort of these foods with additives, we’ll have and create this growing resistance as well. So you actually might feel more and more hungry as you start eating.

Narrator: Anthropologist Margaret Mead famously wrote that  “food is for gifting”, meaning that food provides us with something more than simply nutrition.  The rituals of a shared meal are important to everyone, but they are of particular significance to children.
Sfx- dinner table conversation
The concept of the family meal is a relatively modern development.  For centuries, children weren’t expected to eat with their parents – or speak at the table if they did.  (some parents today refer to this as the “golden age”…) Sfx – fussy baby noises
Recent research shows that regularly sharing meals, with active conversation, improves a child’s vocabulary and self-esteem. It also gives kids and teens the opportunity to hear about current events, and offer their own opinions about the news.
Today, digital technology has had an impact on dinnertime. Linguistic anthropologist Kathleen Riley of Rutgers University points out that “when people look at their devices and send photos of their meal on social media, instead of talking to each other while they eat, they lose so much of the multi-sensuous aspects of food.”
Of course,  Riley also observed that eating together is not the norm in all cultures.  And those who do have family meals often don’t talk while eating — in the Polynesian islands of The Marquesas, for example, it’s considered distracting. What adults there want to represent to children is an attentiveness to their food — and gratitude for it.
Closing theme music
Eating in silent gratitude – now there’s something you may want to try the next time you have to invite all those  relatives over for the holidays!
End Interstitial 

Phil Stieg: What got you interested in this in the first place?

Lauren Breithaupt: Growing up I had a close friend of mine who had an eating disorder when we were both really young.  I was totally perplexed by this because I remember right before she went to treatment, when she was really sick, she told me that she didn’t want to be this way. And in my naive 10-year-old brain, I thought, well then, fix this. I don’t I don’t get why you won’t just solve this problem. It makes no sense to me that this individual just couldn’t change. And I think really it did stick with me all throughout undergrad into my PhD and throughout that there must be sort of this biological component to these eating disorders, because I had never then met someone that had an eating disorder and said that they wanted to be that way.

Phil Stieg: You touched upon it a little bit earlier, but can you tick through the way these disorders are treated now?  Is there a medicine and also cognitive behavioral therapy, psychological therapy, cognitive remediation?  Please touch upon those.

Lauren Breithaupt: Yeah.  So there’s not any approved medication for anorexia nervosa or bulimia nervosa. There’s some evidence of medications being effective for binge eating disorder. Yet, that’s still sort of not always the first standard or gold standard as well. Most effective for binge eating disorder is in fact medication plus therapy. The gold standard of treatment that we currently have is cognitive behavioral therapy for adults with eating disorders, but for adolescents with eating disorders, it’s family-based treatment.  This is actually really bringing in the family to every single session and then capitalizing on the fact that the family knows best how to refeed their child and having the family actually help to re-feed their child, allowing them to still live at home rather than in a hospital.  And then once they are able to be fed, also making sure the family understands that they have to actually continue to monitor the child.

Phil Stieg: It’s family related therapy then not because the family’s dysfunctional, but because the family knows and loves the individual the most and everybody’s got to work together to help them get better.

Lauren Breithaupt: Exactly.

Phil Stieg: So you referred to something called refeeding or refeed. What is that?

Lauren Breithaupt: Yeah, this idea that basically you can feed your child again. The first part for all different types of eating disorder treatments is to help someone develop a regular pattern of eating, which simply means eating breakfast, lunch and dinner and two to three snacks. Getting someone to regularly eat because this actually helps us regulate those hormones that I talked about earlier, ghrelin and leptin. So that way they’re turning on and off at the right times as well.

Phil Stieg: Being a scientist, I’m presuming you’re looking for some way to treat this medically rather than psychologically. Where are you trying to go with this?

Lauren Breithaupt: I think one of the things for me is that I would really love to see us actually be able to develop a treatment that is more biologically based. So ideally, a medication would be great. I mean, family-based treatment is effective because we recognize that it’s too much basically to ask of the individual to be able to do this on their own.  We’re actually asking them to overcome their biology. So it’d be great if actually we could work towards developing a medication to actually target biology itself.  There’s a lot out there and not a lot coming to fruition yet.

Phil Stieg: Complex to me, however, is the associated psychological problems. You’ve got anxiety, you’ve got depression. Is it the chicken or the egg again? You know, which came first? Was it the anxiety and the depression and then they developed the eating disorder? Or are they just two separate problems and you’ve got to treat them separately?

Lauren Breithaupt: So in terms of the medication itself, for anxiety and depression, sometimes actually don’t even work in individuals with eating disorders because some of those medications actually rely on there being the presence of body fat. So those medications for anxiety and depression might not even be effective in terms of if the anxiety or the depression comes first;  we’ve seen both. We see oftentimes individuals will have sort of anxiety as a kid later on, develop an eating disorder.   But actually the treatment sometimes causes someone to feel more anxious. Oftentimes individuals with eating disorders will describe that once they start treatment, they feel worse at first during this period of time where they’re eating again.

Phil Stieg: Always like to end on a happy note, when we when we talk about treatment for these disorders, how successful are we nowadays?

Lauren Breithaupt: Umm, Maybe we should choose a different happy note?

Phil Stieg: (laugh) OK, let me rephrase the question. Thinking about the treatment options that we have available currently what can we say? How successful is it?

Lauren Breithaupt: So we’re about 50 percent effective across all different types of  treatment. One thing I think, though, that is true is that we do know over time, 80 percent of individuals with eating disorders do meet recovery. I think the hard part of that is now we’re talking twenty five years later. Do you really want to see someone have this disorder for twenty five years? And is that really effective at treatment or is this the passage of time?

Phil Stieg: One of the things I’m also surprised about is the family all of a sudden realizes one of their loved ones has a restrictive eating disorder. They go, “my God, I never thought so.”  What are the signs and symptoms that moms and dads should be looking out for?

Lauren Breithaupt: I think any time, you know, noticing a kid  is missing different meals or skipping a meal, avoiding different family meals, I feel like is a really, really big one. So I always say, you know, it is actually great. There’s so many reasons for our family to eat together. This just happens to be one benefit. But eating together can be a really important part to check in on if kids are even willing to eat with family members as well.

Phil Stieg: Treatment is now fifty percent successful.  Was it was there no treatment ten years ago, or were we far less successful ten years ago?

Lauren Breithaupt: Recovery from an eating disorder is definitely possible. We see it happen all the time. I see it happen with most of the patients that I do work with. I think one of the greatest changes, though, for eating disorder treatment is actually recognizing that there is a biological basis to these disorders. Some of the treatments that we do have are effective. The hard part is finding someone that does have the specialized
training in eating disorders, which is sort of the bigger problem I think, that we face.

Phil Stieg: I can imagine there are a lot of quacks in this area. You know, let me help you with your diet. What’s a good website to go to?

Lauren Breithaupt: There’s two websites that I would definitely recommend. The first one is the National Eating Disorders Association, and the second one is the National Center for Excellence in Eating Disorders, which is a newly created center and it really focuses on training and education of evidence-based treatments.  So the treatments that we know work for eating disorders itself.

Phil Stieg: Dr. Lauren Breithaupt. For me, you’ve provided hope because this is a difficult, difficult problem for many individuals. You indicated that it’s millions.  And I’m very happy to see that we’re making progress in terms of our biological understanding, but also in terms of our psychological therapies that we can offer to these individuals. Thank you so much for being with us today.

Lauren Breithaupt: Thank you, I’m excited to be able to be here, too.