Learn. Share. Evolve…

0:00:02 – Welcome to Huberman Lab Essentials,
0:00:04 where we revisit past episodes
0:00:07 for the most potent and actionable science-based tools
0:00:10 for mental health, physical health, and performance.
0:00:12 I’m Andrew Huberman,
0:00:15 and I’m a professor of neurobiology and ophthalmology
0:00:17 at Stanford School of Medicine.
0:00:20 Today, we are going to talk all about healthy
0:00:21 and disordered eating.
0:00:23 And indeed, we are going to talk about
0:00:24 clinical eating disorders,
0:00:29 such as anorexia, bulimia, and binge eating disorder,
0:00:32 as well as some other related eating disorders.
0:00:34 However, before we get into this material,
0:00:38 I want to emphasize that today’s discussion will include
0:00:41 what it is to have a healthy relationship with food.
0:00:44 We are going to talk about metabolism.
0:00:46 We are going to talk about how eating frequency
0:00:51 and what one eats influences things like appetite and satiety,
0:00:54 as well as whether or not we have
0:00:57 a healthy psychological relationship to food
0:01:00 and our body weight and so-called body composition,
0:01:04 the ratio of muscle to fat to bone, et cetera.
0:01:07 So as we march into this conversation,
0:01:09 I’d like to share with you some interesting
0:01:11 and what I believe are important findings
0:01:15 in the realm of nutrition and human behavior.
0:01:18 I know these days, many people are excited about
0:01:21 or curious about so-called intermittent fasting.
0:01:24 Intermittent fasting is, as the name implies,
0:01:28 simply restricting one’s feeding behavior, eating,
0:01:31 to a particular phase of the 24-hour
0:01:33 or so-called circadian cycle.
0:01:37 Other forms of intermittent fasting involve not eating
0:01:40 for extended periods of time, for entire days,
0:01:43 or some people will extend to two days or three days.
0:01:46 Typically, and hopefully, they will drink water
0:01:50 during those times, sometimes referred to as water fasting,
0:01:52 which means that they are ingesting fluids,
0:01:55 and hopefully they are ingesting electrolytes,
0:01:57 such as salt, potassium, and magnesium as well,
0:02:02 because while one can survive for some period of time
0:02:04 without ingesting calories,
0:02:06 it is extremely important to continue
0:02:10 to ingest plenty of fluids and electrolytes.
0:02:12 And the reason for that is that the neurons
0:02:14 of your brain and body that control your movements,
0:02:18 your thoughts, clarity of thinking in general, et cetera,
0:02:22 is critically dependent on the presence of adequate levels
0:02:26 of sodium, potassium, and magnesium, the electrolytes.
0:02:28 And that’s because neurons can only be electrically active
0:02:31 by way of movement of particular ions,
0:02:34 which include things like sodium, potassium, and magnesium.
0:02:37 So without those, you can’t think, you can’t function,
0:02:39 and it actually can be quite dangerous.
0:02:42 So why all the excitement about intermittent fasting?
0:02:45 Well, a lot of the excitement relates to work
0:02:47 that was done by a former colleague of mine
0:02:50 down at the Salk Institute for Biological Studies
0:02:51 in San Diego named Sachin Panda.
0:02:55 Sachin’s lab identified some very important
0:02:57 and impactful health benefits
0:03:00 of restricting one’s feeding window
0:03:02 to particular times within the 24-hour cycle,
0:03:07 or even to having extended fasts that go for a day
0:03:08 or two days or maybe even three days.
0:03:13 What they saw was an improvement in liver enzymes,
0:03:15 an improvement in insulin sensitivity,
0:03:17 which is something that is good.
0:03:20 It means that you can utilize the calories
0:03:23 and the blood sugar that you happen to have.
0:03:25 Being insulin insensitive is not good
0:03:28 and is actually a form of diabetes.
0:03:33 What Sachin’s lab and subsequently other labs showed
0:03:35 was that restricting one’s feeding window
0:03:39 to anywhere from four to eight or even 12 hours
0:03:42 during each 24-hour cycle was beneficial in mice.
0:03:45 And some studies in humans have also shown
0:03:47 that it can be beneficial for various health parameters.
0:03:51 However, the excitement about intermittent fasting
0:03:56 seems to be related to the foundational truth
0:03:59 about metabolism and weight loss
0:04:01 and weight maintenance and weight gain,
0:04:04 which is that regardless of whether or not
0:04:05 you intermittent fast
0:04:08 or whether or not you eat small meals all day long
0:04:10 or you eat one meal in the evening
0:04:11 and snack up until then,
0:04:15 it really doesn’t matter in the sense
0:04:19 that the calories that you ingest from whatever source
0:04:23 are going to be filtered through the calories
0:04:26 that you burn by way of exercise,
0:04:27 basal metabolic rate,
0:04:29 which is just the calories that you happen to burn,
0:04:32 just being alive and thinking and breathing
0:04:33 and your heart beating, et cetera.
0:04:38 And the reason why many people prefer intermittent fasting
0:04:41 to other forms of, let’s just call it what it is,
0:04:43 diet or nutritional framework,
0:04:47 is that many people find it easier to not eat
0:04:50 than to limit their portion size.
0:04:53 And here I’m not talking necessarily about eating disorders,
0:04:54 I’m talking about the general population.
0:04:56 So why are we talking about this?
0:04:59 And in particular, why are we talking about this
0:05:01 during an episode that includes a discussion
0:05:02 about eating disorders?
0:05:07 The reason is nobody, not the government,
0:05:09 no nutritionists, no individual,
0:05:13 no matter how knowledgeable they are about food
0:05:14 and nutrition and food intake,
0:05:19 can define the best plan for eating for any one individual.
0:05:21 I’m going to repeat that.
0:05:25 Nobody knows what truly healthy eating is.
0:05:27 We only know the measurements we can take,
0:05:31 liver enzymes, blood lipid profiles, body weight,
0:05:34 athletic performance, mental performance,
0:05:36 whether or not you’re cranky all day,
0:05:37 whether or not you’re feeling relaxed.
0:05:39 Nobody knows how to define these.
0:05:43 And these have strong cultural and familial
0:05:46 and socio-societal influence.
0:05:50 So if you hang out with people that intermittent fast all day,
0:05:51 that will seem normal.
0:05:52 If you spend time with people
0:05:54 that have never heard of intermittent fasting,
0:05:57 intermittent fasting is going to seem very abnormal.
0:05:59 Now, we are going to talk about eating disorders
0:06:01 that really fall into the category
0:06:04 of clinically diagnosable eating disorders
0:06:07 for which there’s actually serious health hazards
0:06:09 and even the serious risk of death.
0:06:12 There are clear criteria in the psychiatric
0:06:13 and psychological communities
0:06:17 to define things like anorexia, bulimia,
0:06:18 binge eating disorder,
0:06:19 all of which we will talk about.
0:06:21 But as we have that discussion,
0:06:24 I want to emphasize that self-diagnosis
0:06:28 can be both a terrific but also a very precarious thing.
0:06:30 There’s always a temptation
0:06:33 as one learns about the symptomology of a given disorder,
0:06:35 doesn’t really matter what the disorder is,
0:06:37 to ask the question,
0:06:38 well, do I have that?
0:06:40 Does so-and-so that I know have that?
0:06:42 It’s tempting to diagnose them and or ourselves
0:06:45 as either having or not having a particular disorder.
0:06:50 However, diagnoses really need to be carried out
0:06:53 by people who are trained in that particular field
0:06:54 and that have deep expertise
0:06:56 in recognizing the symptomology,
0:06:59 including some of the more subtle symptomology
0:07:00 of eating disorders.
0:07:03 So if any of the symptoms resonate with you
0:07:06 by way of you thinking
0:07:07 that you have this particular disorder
0:07:09 or someone that you know has a disorder,
0:07:11 I would take that seriously,
0:07:13 but I would take that information
0:07:15 to a qualified healthcare professional
0:07:18 that could diagnose or rule out
0:07:19 any of these possible disorders.
0:07:21 I’d like to take a quick break
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0:08:53 So what is an eating disorder?
0:08:56 Well, we have to take a step back
0:08:58 and confess to the fact
0:09:00 that every society, every culture,
0:09:01 every family,
0:09:02 and every individual
0:09:04 has a different relationship to food.
0:09:06 Eating disorders, however,
0:09:08 have particular criteria
0:09:10 that allow us to define them
0:09:13 and to think about different modes of treatment
0:09:15 as it relates
0:09:17 to the particular symptoms,
0:09:18 in particular,
0:09:20 the psychological and biological symptoms
0:09:21 of those disorders.
0:09:23 What are the major eating disorders?
0:09:26 Anorexia nervosa,
0:09:29 most commonly referred to as anorexia,
0:09:32 is perhaps the most prevalent
0:09:34 and the most dangerous
0:09:35 of all eating disorders.
0:09:37 In fact,
0:09:39 anorexia is the most dangerous
0:09:40 psychiatric disorder of all,
0:09:42 even more than depression.
0:09:45 the probability of death
0:09:47 for untreated anorexia
0:09:48 is very high.
0:09:50 And sadly,
0:09:51 the prevalence of anorexia
0:09:52 is very high.
0:09:54 If you look it up online
0:09:55 or you talk to a qualified professional,
0:09:57 it’s essentially a failure
0:09:58 to eat enough
0:09:59 to maintain a healthy weight.
0:10:01 You can see all sorts
0:10:04 of very troubling symptoms
0:10:05 of somebody who’s been anorexic
0:10:06 for some period of time,
0:10:10 a general loss of muscle mass
0:10:12 because they’re ingesting fewer calories
0:10:13 than they burn.
0:10:15 They will have a low heart rate.
0:10:17 This is the body
0:10:18 and brain’s attempt
0:10:19 to lower energy output.
0:10:21 They will have low blood pressure.
0:10:23 They will sometimes have symptoms
0:10:24 like fainting,
0:10:26 loss of bone density,
0:10:28 osteoporosis,
0:10:29 loss of periods
0:10:31 in girls and women,
0:10:35 and all sorts of disrupted gut
0:10:36 and immune functions.
0:10:38 So there are just tons
0:10:39 of terrible symptoms
0:10:40 of anorexia
0:10:41 that really place
0:10:42 the anorexic
0:10:45 into a very risky state,
0:10:47 which is why mortality
0:10:49 from anorexia gone untreated
0:10:50 is extremely high.
0:10:53 Now, one of the misconceptions
0:10:55 about anorexia
0:10:57 is that it stems
0:10:58 from an overemphasis
0:10:59 on perfectionism
0:11:00 or that because
0:11:02 of all the images
0:11:03 in social media
0:11:05 and in advertising
0:11:07 of extremely thin
0:11:07 and fit
0:11:07 and fit
0:11:08 or muscular people
0:11:10 that individuals
0:11:11 are looking at themselves
0:11:12 and comparing themselves
0:11:13 to those images
0:11:14 and thinking
0:11:15 that they don’t match up
0:11:17 and developing anorexia.
0:11:19 That turns out
0:11:20 to not be the case.
0:11:21 If you look
0:11:22 at the prevalence
0:11:23 or the rates
0:11:24 of anorexia
0:11:26 in the last 10 years
0:11:27 or 20 years
0:11:28 and you compare that
0:11:29 to when anorexia
0:11:30 was first identified,
0:11:32 which was in the 1600s
0:11:33 and perhaps even earlier,
0:11:34 what you find
0:11:36 is that rates
0:11:36 of anorexia
0:11:37 are not going up.
0:11:39 Classically defined anorexia
0:11:40 has existed
0:11:41 at essentially
0:11:42 the same prevalence
0:11:45 for the last 100,
0:11:45 200,
0:11:46 300,
0:11:47 and 400 years,
0:11:48 which is incredible
0:11:49 and really speaks
0:11:50 to the likelihood
0:11:52 that there’s a strong
0:11:53 biological contribution
0:11:54 to what we call
0:11:55 anorexia nervosa.
0:11:57 Anorexia nervosa
0:11:58 is extremely common.
0:11:59 It’s anywhere
0:12:02 from 1% to 2%
0:12:03 of women
0:12:05 and the typical onset
0:12:06 is in adolescence,
0:12:07 close to puberty,
0:12:09 but it can show up
0:12:10 later in life as well.
0:12:11 In fact,
0:12:13 the identification
0:12:14 and diagnosis
0:12:15 of anorexia
0:12:15 tends to be
0:12:17 in the early 20s,
0:12:19 but if you look back
0:12:19 at the history
0:12:20 of those individuals,
0:12:21 there were typically
0:12:23 signs of anorexia
0:12:23 that stem back
0:12:24 into their early teens
0:12:26 or maybe even before that.
0:12:27 Now, of course,
0:12:28 men can be anorexic
0:12:29 as well,
0:12:30 but anorexia nervosa
0:12:31 does seem to occur
0:12:33 at 10 times
0:12:33 the rate
0:12:34 in women
0:12:35 and young girls
0:12:36 than it does
0:12:37 in men
0:12:38 and young boys.
0:12:40 So what is hunger
0:12:41 and what is satiety?
0:12:41 Satiety,
0:12:42 of course,
0:12:43 being sated
0:12:43 or feeling
0:12:44 like we’ve had
0:12:45 enough food.
0:12:46 I want to remind people
0:12:48 of the basic mechanisms
0:12:49 by which the brain
0:12:50 and body communicate.
0:12:51 The body
0:12:52 is communicating
0:12:53 two types of information
0:12:53 to the brain
0:12:55 on a regular basis,
0:12:56 but in particular
0:12:57 around feeding.
0:12:58 and those two types
0:12:59 of information
0:13:00 are mechanical information
0:13:03 and chemical information.
0:13:04 When your stomach
0:13:05 is full,
0:13:06 it sends signals
0:13:07 to your brain
0:13:08 that are purely based
0:13:09 on this mechanical fullness.
0:13:10 That’s nothing
0:13:11 to do with nutrients
0:13:12 that says,
0:13:13 I’m full
0:13:15 and therefore
0:13:17 don’t be as hungry.
0:13:17 Don’t motivate
0:13:18 to find
0:13:19 or ingest food.
0:13:20 Whereas when our gut
0:13:21 is empty,
0:13:22 even if we have plenty
0:13:23 of nutrients
0:13:25 or plenty of body fat stores,
0:13:26 we tend to focus
0:13:27 on food a bit more.
0:13:29 So volume
0:13:31 and mechanical influences
0:13:32 have a profound effect
0:13:33 on how we think
0:13:34 and what we consider
0:13:35 doing or not doing.
0:13:36 Likewise,
0:13:37 chemical effects.
0:13:39 When we ingest food,
0:13:40 our blood glucose goes up.
0:13:41 That information
0:13:42 is signaled to the brain
0:13:45 via neuronal pathways
0:13:46 and hormonal pathways.
0:13:48 And in particular,
0:13:49 there are neurons
0:13:50 within our gut
0:13:51 that signal to areas
0:13:52 of our brainstem
0:13:52 that are involved
0:13:53 in satiety
0:13:54 in our sense
0:13:54 of having enough
0:13:55 that there’s food
0:13:56 in our system.
0:13:58 So that’s chemical information.
0:14:01 So how are hunger
0:14:02 and feeding
0:14:03 and satiety regulated?
0:14:05 By way of mechanical
0:14:06 and chemical signaling.
0:14:08 You have,
0:14:08 I have,
0:14:09 we all have
0:14:11 neurons in our hypothalamus
0:14:12 that trigger eating
0:14:14 and neurons
0:14:15 that trigger
0:14:16 cessation
0:14:17 or stopping of eating.
0:14:18 Your hypothalamus
0:14:19 at the base
0:14:19 of your forebrain
0:14:20 sits more or less
0:14:21 above the roof
0:14:21 of your mouth.
0:14:22 The hypothalamus
0:14:23 contains lots
0:14:24 of different kinds
0:14:24 of neurons.
0:14:25 including neurons
0:14:26 that stimulate
0:14:27 sexual activity
0:14:28 and desire,
0:14:30 regulate your body temperature
0:14:32 and control appetite
0:14:33 and ceasing
0:14:34 of eating
0:14:35 and appetite.
0:14:38 There are two types
0:14:38 of neurons
0:14:39 within a particular area
0:14:40 of your hypothalamus
0:14:41 that are relevant here.
0:14:42 There are the so-called
0:14:45 POMC neurons.
0:14:46 Okay?
0:14:48 Pro-opioid melanocortin neurons
0:14:50 that tend to act
0:14:51 as more of a break
0:14:53 on appetite
0:14:55 by way of another hormone
0:14:56 called melanocyte
0:14:57 stimulating hormone.
0:14:58 And you have a class
0:14:58 of neurons
0:15:00 called the AGRP neurons.
0:15:01 The AGRP neurons
0:15:01 are the ones
0:15:03 that stimulate feeding
0:15:04 and they create
0:15:05 a sort of anxiety
0:15:06 or excitement
0:15:07 about food.
0:15:09 If you eliminate
0:15:10 or kill these neurons,
0:15:11 which has been done
0:15:13 in experimental mouse models
0:15:14 in the laboratory,
0:15:15 but also there are humans
0:15:15 that have lesions
0:15:17 or neurotoxic effects
0:15:18 on these AGRP neurons.
0:15:20 And what you find
0:15:21 is that they don’t want to eat.
0:15:22 They have no appetite
0:15:23 for food whatsoever.
0:15:25 Whereas if you stimulate
0:15:26 these AGRP neurons
0:15:27 or in humans
0:15:28 that have say
0:15:29 a small tumor
0:15:30 near these AGRP neurons,
0:15:32 they become hyperphagic.
0:15:32 They will eat
0:15:33 to the point of bursting.
0:15:35 Now there are signals
0:15:36 coming back
0:15:37 from the body
0:15:38 to inform the brain
0:15:39 about presence
0:15:40 of different levels
0:15:41 of nutrients.
0:15:41 And that generally
0:15:43 comes from three sources.
0:15:44 first of all
0:15:46 is body fat.
0:15:48 The more body fat we have,
0:15:49 the more we secrete
0:15:50 a hormone called leptin,
0:15:51 L-E-P-T-I-N,
0:15:53 leptin from body fat.
0:15:55 Leptin goes to the brain
0:15:57 and suppresses appetite.
0:15:58 Not incidentally,
0:16:00 leptin signaling
0:16:01 is disrupted
0:16:02 in people
0:16:03 that have bulimia
0:16:04 and obesity
0:16:05 and certain forms
0:16:07 of binge eating disorder.
0:16:08 The body fat
0:16:09 is doing something else
0:16:09 really interesting
0:16:11 that relates to anorexia.
0:16:13 When there’s sufficient levels
0:16:13 of body fat
0:16:15 and leptin circulating
0:16:16 in the blood
0:16:17 and that leptin signal
0:16:18 gets to the brain,
0:16:20 the hypothalamus
0:16:21 and the pituitary gland
0:16:22 register that signal
0:16:24 and in a completely
0:16:25 subconscious way
0:16:26 trigger
0:16:28 the deployment
0:16:28 of eggs
0:16:30 in females
0:16:31 and the production
0:16:32 of sperm
0:16:32 in males.
0:16:34 So when body fat stores
0:16:35 are very low,
0:16:36 the reason why
0:16:37 periods shut off
0:16:38 or sperm production
0:16:39 is reduced
0:16:40 or even shut off
0:16:41 is because there’s
0:16:42 not enough leptin
0:16:44 getting to the hypothalamus
0:16:45 and to the pituitary
0:16:47 and they shut off
0:16:48 the signals,
0:16:49 the hormones,
0:16:50 things like gonadotropin,
0:16:50 releasing hormone,
0:16:51 luteinizing hormone,
0:16:52 follicle stimulating hormone
0:16:54 that travel to the ovary
0:16:55 or to the testes
0:16:56 and cause the ovary
0:16:56 and testes
0:16:57 to ovulate
0:16:58 or to produce
0:17:00 more sperm.
0:17:00 So you’ve got
0:17:01 two categories of neurons,
0:17:02 one that acts
0:17:03 as an accelerator,
0:17:04 the AGRP neuron
0:17:05 saying eat,
0:17:05 eat
0:17:07 and gets you excited
0:17:07 to eat
0:17:08 and then you have
0:17:09 a category of neurons,
0:17:10 the PMOC neurons
0:17:13 that are suppressing hunger,
0:17:14 they’re acting like a brake
0:17:15 and the body
0:17:16 is informing the brain
0:17:17 all the time
0:17:17 about the status
0:17:18 of the body
0:17:18 and whether or not
0:17:19 it needs more food.
0:17:20 So you might ask,
0:17:21 why is it
0:17:22 that people who are overweight
0:17:23 and have a lot of body fat,
0:17:24 why they would continue
0:17:25 to eat a lot?
0:17:26 It seems like
0:17:27 that just shouldn’t happen.
0:17:29 From an evolutionary standpoint,
0:17:31 it makes sense
0:17:32 that we should eat
0:17:34 as often as we can,
0:17:35 as much as we can
0:17:37 and as fast as we can.
0:17:38 There are circuits
0:17:38 in the brain
0:17:40 to reward eating often,
0:17:41 eating fast
0:17:43 and cramming
0:17:43 as much food
0:17:44 into you as possible
0:17:46 because from a purely
0:17:47 evolutionary standpoint,
0:17:49 food was scarce
0:17:50 and seeking food
0:17:51 was dangerous
0:17:52 whether or not
0:17:53 it was from animal sources
0:17:53 or not
0:17:55 and it’s always
0:17:56 been competitive.
0:17:57 Every animal,
0:17:58 including humans,
0:18:00 has a hardwired
0:18:00 circuit
0:18:01 that we were born
0:18:03 with that pays attention
0:18:04 to how much food
0:18:05 is available,
0:18:06 how much we are getting
0:18:07 now and how much
0:18:08 we are likely to get
0:18:09 in the future
0:18:11 and without going down
0:18:12 the rabbit hole
0:18:14 of arcuate nucleus biology,
0:18:17 in two sentences,
0:18:19 you have a hypothalamic area
0:18:20 called the arcuate nucleus.
0:18:21 It’s actually the area
0:18:22 that houses
0:18:23 these PMOC neurons
0:18:24 and these other types
0:18:24 of neurons
0:18:25 that regulate hunger
0:18:26 and satiety
0:18:29 and these neurons
0:18:30 in the arcuate nucleus
0:18:31 start getting active
0:18:33 when we see food
0:18:34 and think about food
0:18:35 and they drive hunger
0:18:36 in a way
0:18:36 that’s responsive
0:18:37 to what the food
0:18:38 looks like,
0:18:40 what it smells like,
0:18:42 but also our prior history
0:18:43 of interactions
0:18:43 with that food
0:18:45 and it takes into account
0:18:47 social context.
0:18:48 What’s the pathway?
0:18:48 How does this work?
0:18:52 Well, you can frame
0:18:53 all of behavior,
0:18:55 good decision-making
0:18:56 and bad decision-making
0:18:57 in a pretty simple
0:18:59 box diagram model.
0:19:01 We have knowledge
0:19:02 of what we should do
0:19:03 in one box, okay?
0:19:04 We should eat that,
0:19:05 we shouldn’t eat that,
0:19:06 we should wait for dinner,
0:19:07 we shouldn’t wait for dinner
0:19:08 and then we have
0:19:09 what we actually do
0:19:11 in another box.
0:19:13 In between those two boxes
0:19:15 are two intervening forces
0:19:16 and those intervening forces
0:19:18 are critically important.
0:19:19 those intervening forces
0:19:21 are homeostatic processes
0:19:23 that regulate the balance
0:19:25 of different systems
0:19:25 in your body,
0:19:26 hot and cold,
0:19:27 awake or asleep,
0:19:30 dopamine and the desire
0:19:31 to pursue things,
0:19:32 serotonin and the desire
0:19:34 to just relax and chill.
0:19:36 So homeostatic processes
0:19:38 and reward systems
0:19:40 and as we now move
0:19:41 into discussion
0:19:42 about anorexia
0:19:43 and bulimia specifically,
0:19:45 what you’ll see
0:19:47 is that anorexia and bulimia
0:19:49 are not a breaking
0:19:51 of the mindset
0:19:52 of what one should do
0:19:53 or shouldn’t do.
0:19:55 It’s a disruption
0:19:56 of these homeostatic
0:19:57 and reward processes
0:20:00 such that decision-making
0:20:01 is completely disrupted
0:20:02 and in many cases
0:20:03 is not available
0:20:05 to the anorexic or bulimic.
0:20:06 Now, I don’t want
0:20:07 to be abstract here.
0:20:07 What I’m saying is
0:20:09 that the person
0:20:11 who starves themselves
0:20:11 to the point
0:20:12 where they might die
0:20:13 and in some cases
0:20:14 sadly do die,
0:20:16 they can know perfectly well
0:20:17 that their behavior
0:20:20 is leading to bad outcomes
0:20:22 and possibly even death
0:20:24 and yet they are not able
0:20:25 to intervene
0:20:26 unless they get
0:20:28 particular clinical help
0:20:31 because the homeostatic processes,
0:20:32 the signals from the body
0:20:33 and brain that say
0:20:34 you need food,
0:20:36 those aren’t registering
0:20:37 in the same way
0:20:38 that they are
0:20:39 for other individuals
0:20:40 and just as a little teaser
0:20:41 of where we’re headed,
0:20:44 anorexics have a sort of switch
0:20:45 that’s been flipped
0:20:48 such that their decision-making
0:20:50 is actually pretty darn good.
0:20:51 It might even be better
0:20:51 than yours
0:20:52 in terms of evaluating
0:20:54 food nutritional content
0:20:55 but their habits
0:20:56 are disrupted
0:20:57 so they’re not even
0:20:59 consciously aware
0:20:59 of the fact
0:21:00 that they’re making terrible
0:21:01 and in some cases
0:21:03 very dangerous food choices.
0:21:04 It turns out habits
0:21:06 and the way that we build
0:21:07 and break
0:21:09 and rebuild new habits
0:21:10 is one of the most
0:21:11 effective treatments
0:21:11 for anorexia.
0:21:13 I’d like to take
0:21:13 a quick break
0:21:14 and acknowledge
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0:22:49 So now let’s talk
0:22:50 about anorexia,
0:22:51 this failure
0:22:52 to consume enough energy
0:22:53 such that the individual
0:22:55 is at risk of death
0:22:56 and if not death,
0:22:58 then severe metabolic disorders,
0:23:00 lack of bone density,
0:23:01 et cetera.
0:23:02 A careful analysis
0:23:04 through medical epidemiology
0:23:05 has shown
0:23:06 that you find anorexia
0:23:07 even in cultures
0:23:08 and societies
0:23:09 where food is scarce.
0:23:11 So that really speaks
0:23:13 to biological mechanism.
0:23:13 Typically,
0:23:14 anorexia starts
0:23:15 in adolescence
0:23:16 right around puberty.
0:23:17 Puberty
0:23:19 at a very broad level
0:23:21 is the most significant
0:23:23 and dramatic developmental step
0:23:24 anyone goes through
0:23:24 in their lifespan.
0:23:25 The body changes,
0:23:26 the brain changes,
0:23:27 perceptions change,
0:23:29 one’s own self-perception
0:23:30 changes.
0:23:32 And most of those changes
0:23:33 are driven by changes
0:23:34 in circuitry
0:23:36 within the hypothalamus.
0:23:37 So neurons
0:23:37 that are controlling
0:23:38 the production
0:23:39 of the so-called
0:23:40 sex steroid hormones,
0:23:41 things like testosterone,
0:23:41 estrogen,
0:23:42 and related hormones,
0:23:43 prolactin,
0:23:43 et cetera,
0:23:45 those are all changing
0:23:46 at very rapid rates.
0:23:48 Let’s look under the hood.
0:23:50 Let’s look at what’s known
0:23:51 about the neural circuitry
0:23:52 and the sorts of perceptions
0:23:53 and behaviors
0:23:54 of the neural circuitry
0:23:55 is driving
0:23:56 in order to understand
0:23:58 what they are truly
0:23:59 suffering from
0:24:00 at the level of cause,
0:24:01 not just symptoms.
0:24:03 First of all,
0:24:04 there’s a challenge
0:24:05 in studying anorexia
0:24:06 because in anorexia,
0:24:07 what you’re essentially studying
0:24:09 is the absence
0:24:09 of a behavior.
0:24:10 It’s very hard
0:24:11 to study
0:24:12 the absence
0:24:12 of a behavior
0:24:13 as opposed
0:24:14 to a behavior.
0:24:15 So they did
0:24:16 some experiments
0:24:17 with anorexics,
0:24:17 giving them
0:24:19 a gallery
0:24:19 of pictures
0:24:20 of different foods
0:24:21 and allowing
0:24:23 those anorexic patients
0:24:25 to arrange those foods
0:24:26 according to preference
0:24:28 about what they would select,
0:24:31 about food nutrient content,
0:24:32 about caloric content.
0:24:33 They essentially
0:24:34 asked these anorexics
0:24:36 to evaluate food
0:24:37 and in doing so,
0:24:38 they were able
0:24:38 to identify
0:24:39 something that’s
0:24:40 very unique
0:24:41 to anorexics
0:24:42 at the level
0:24:43 of their perception
0:24:44 of food.
0:24:45 Anorexics,
0:24:47 rather than being anxious
0:24:48 in the presence
0:24:48 of food,
0:24:50 have a hyperacuity,
0:24:51 a hyperawareness
0:24:52 of the fat content
0:24:53 of foods,
0:24:54 almost to the point
0:24:55 of being sort of
0:24:56 fat content savants.
0:24:57 Now,
0:24:58 it’s a well-known
0:24:59 symptom of anorexia,
0:25:02 especially young anorexics
0:25:02 that they have
0:25:04 kind of an obsession
0:25:05 with food,
0:25:06 caloric contents,
0:25:07 macronutrient ratios,
0:25:08 meaning fat,
0:25:08 protein,
0:25:10 and carbohydrate ratios.
0:25:12 They are actively
0:25:13 avoiding
0:25:15 high-fat content foods,
0:25:16 calorie-rich foods,
0:25:17 and defaulting
0:25:18 towards
0:25:19 very low-calorie foods
0:25:21 if they have to eat.
0:25:23 And that’s very important
0:25:24 because what that means
0:25:25 is that we need
0:25:25 to look at
0:25:26 the areas of the brain
0:25:27 that drive
0:25:29 habit formation
0:25:31 and habit execution.
0:25:32 In the case
0:25:32 of the anorexic,
0:25:34 those habits
0:25:35 are exactly
0:25:36 the place
0:25:36 where things
0:25:37 start to go awry
0:25:39 and that drive
0:25:39 this very
0:25:41 dysfunctional,
0:25:41 under-eating behavior
0:25:43 that sadly
0:25:43 often leads
0:25:44 to death
0:25:45 or certainly
0:25:46 bad medical outcomes.
0:25:47 And it turns out
0:25:49 that the brain areas
0:25:50 associated with
0:25:51 habit formation
0:25:52 and execution
0:25:53 are the best
0:25:54 point of intervention.
0:25:55 So
0:25:57 you have reflexes
0:25:59 and you have
0:26:01 neural processes
0:26:02 that include
0:26:03 what are called
0:26:04 duration path
0:26:04 and outcome
0:26:05 type processes.
0:26:06 A duration path
0:26:07 outcome type process
0:26:08 we can shorten
0:26:09 with DPO.
0:26:11 DPO is
0:26:13 for all types
0:26:14 of goal-related behaviors.
0:26:16 So for instance,
0:26:17 if you want
0:26:17 to go to the grocery store
0:26:18 and pick some stuff up
0:26:20 and then head home,
0:26:21 you’re going to think
0:26:22 duration,
0:26:23 how long do I have?
0:26:23 Okay,
0:26:24 do I have 45 minutes
0:26:25 to get to the store?
0:26:25 How long does it take
0:26:26 to get to the store?
0:26:27 Path,
0:26:28 which way am I going
0:26:28 to drive there?
0:26:29 Which way am I going
0:26:29 to navigate
0:26:30 through the grocery store?
0:26:31 Outcome,
0:26:32 was I able to get in
0:26:33 and get the items
0:26:33 I need
0:26:34 and get home in time?
0:26:35 Okay?
0:26:35 DPO,
0:26:36 duration path outcome.
0:26:37 It’s a very conscious
0:26:39 process that requires
0:26:40 decision-making
0:26:41 and it’s reward-based.
0:26:42 You use these
0:26:44 DPO type processes
0:26:45 in the short term
0:26:47 to pick up groceries
0:26:48 and pick a line
0:26:49 at the grocery store
0:26:50 and decide which
0:26:52 trajectory to take home
0:26:53 and you use them
0:26:54 for navigating
0:26:56 long extended processes
0:26:56 in life,
0:26:57 trying to get a degree
0:26:58 or raise children
0:26:59 or get through
0:27:00 a particularly
0:27:01 challenging year,
0:27:02 et cetera.
0:27:04 So duration path outcome
0:27:06 and that entire process
0:27:07 relies on your
0:27:08 forebrain,
0:27:09 this prefrontal cortex.
0:27:11 The prefrontal cortex
0:27:13 is what allows you
0:27:14 to take information
0:27:14 from memory,
0:27:15 combine it
0:27:16 with information
0:27:17 about what’s happening
0:27:18 in the present context
0:27:20 and then to direct
0:27:20 your behavior,
0:27:22 your speech,
0:27:23 et cetera,
0:27:24 toward particular outcomes.
0:27:25 Reflexes,
0:27:26 on the other hand,
0:27:28 don’t involve
0:27:28 the prefrontal cortex
0:27:29 in the same way.
0:27:31 Habits and reflexes,
0:27:32 like once you know
0:27:32 how to walk,
0:27:34 that doesn’t rely
0:27:34 on prefrontal cortex.
0:27:35 It’s subconscious
0:27:37 as it’s sometimes called,
0:27:37 but basically
0:27:38 you don’t have
0:27:39 to use the parts
0:27:39 of the brain
0:27:40 that are involved
0:27:41 in duration path
0:27:42 and outcome type analyses.
0:27:44 But basically
0:27:45 you have a brain area
0:27:46 and anorexics
0:27:46 have a brain area
0:27:47 that’s involved
0:27:48 in evaluating
0:27:49 and decision-making
0:27:49 around food
0:27:51 and then another brain area
0:27:52 that’s involved
0:27:53 in the reflexive
0:27:54 consumption
0:27:55 of particular foods
0:27:56 and the reflexive
0:27:57 avoidance
0:27:58 of other foods.
0:27:59 There are always
0:28:00 homeostatic
0:28:02 and reward systems
0:28:03 influencing
0:28:04 this kind of thing.
0:28:05 well,
0:28:07 in the brain
0:28:07 of the anorexic,
0:28:09 it turns out
0:28:10 that the reward systems
0:28:11 have been attached
0:28:13 to the execution
0:28:14 of habits
0:28:15 in a way
0:28:16 that is unhealthy
0:28:17 for body weight,
0:28:18 but at least
0:28:19 from a purely
0:28:20 neural circuit perspective,
0:28:22 the reward
0:28:23 is now given,
0:28:24 this chemical reward
0:28:25 in the brain
0:28:25 is given
0:28:26 for avoiding
0:28:27 particular foods
0:28:29 and only approaching
0:28:30 these very low-calorie,
0:28:32 low-fat foods.
0:28:33 so there really
0:28:34 does seem
0:28:35 to be a flip
0:28:36 in the switch
0:28:38 in the anorexic brain
0:28:39 that rewards
0:28:39 them internally.
0:28:41 They feel good
0:28:42 when they avoid
0:28:43 certain foods
0:28:44 and they approach
0:28:44 others.
0:28:45 So it’s not
0:28:46 a deprivation-based
0:28:47 model where
0:28:48 they are
0:28:49 flagellating themselves
0:28:50 or masochistic
0:28:51 or actively
0:28:52 avoiding food
0:28:53 in order to punish
0:28:54 themselves,
0:28:55 which is interesting
0:28:56 because a lot
0:28:57 of psychological theories
0:28:58 support that idea.
0:28:59 rather,
0:29:01 once this transitions
0:29:02 into a set
0:29:03 of habits,
0:29:04 they are actually
0:29:05 getting a sense
0:29:05 of reward.
0:29:07 They feel good,
0:29:07 presumably from
0:29:08 the release
0:29:08 of a different
0:29:09 neuromodulator
0:29:10 called dopamine,
0:29:12 by approaching
0:29:13 foods that are
0:29:14 low-fat,
0:29:15 low-calorie content,
0:29:16 and so their
0:29:17 whole brain circuitry
0:29:18 is skewed
0:29:19 toward avoiding
0:29:20 particular things
0:29:21 and they actually
0:29:22 are rewarded
0:29:22 for that
0:29:24 and they feel good.
0:29:25 they feel better
0:29:26 than if they were
0:29:27 eating in a healthy
0:29:28 weight-supporting way.
0:29:29 So how do you
0:29:30 break a habit?
0:29:31 How do you rewire
0:29:32 the brain circuitry
0:29:32 that’s literally
0:29:33 causing a reflex
0:29:34 and in this case
0:29:35 causing a reflex
0:29:36 that is killing
0:29:37 the individual
0:29:38 or at least leading
0:29:40 to very bad
0:29:40 health outcomes?
0:29:42 The way that you
0:29:44 do that is
0:29:45 through a cognitive
0:29:46 mechanism where
0:29:47 you teach the
0:29:48 individual what
0:29:49 is leading up
0:29:49 to the habit.
0:29:50 So let’s talk
0:29:51 about what those
0:29:53 things are that lead
0:29:53 into a habit.
0:29:54 because those
0:29:55 turn out to be
0:29:56 the exact points
0:29:57 of entry for
0:29:58 changing and
0:29:59 eliminating and
0:30:00 rewiring habits
0:30:01 toward more
0:30:02 healthy behaviors.
0:30:02 There are two
0:30:03 main features of
0:30:04 thinking that go
0:30:05 into the sorts
0:30:06 of habits that
0:30:07 anorexics execute.
0:30:09 The first is
0:30:10 something called
0:30:10 weak central
0:30:11 coherence.
0:30:12 Weak central
0:30:13 coherence is
0:30:14 essentially an
0:30:15 inability to see
0:30:16 the forest through
0:30:17 the trees.
0:30:18 It’s a hyper
0:30:19 acuity and focus
0:30:21 on details within
0:30:21 a given environment.
0:30:22 You miss the
0:30:23 big picture.
0:30:24 The other
0:30:24 is a challenge
0:30:25 in set shifting
0:30:26 that once you
0:30:27 identify something
0:30:28 that’s of particular
0:30:30 interest and that’s
0:30:31 driving some sort
0:30:33 of reward for the
0:30:33 anorexic, that would
0:30:34 be identifying the
0:30:36 high fat foods or
0:30:37 identifying the one
0:30:37 food on the table
0:30:38 that one could eat
0:30:39 without anyone
0:30:40 hopefully noticing
0:30:41 that they’re eating
0:30:43 just the green beans
0:30:44 and not touching any
0:30:45 of the other food.
0:30:46 If you ever had a meal
0:30:47 with an anorexic,
0:30:48 they become masterful
0:30:49 actually at trying
0:30:50 to keep people’s
0:30:51 awareness away
0:30:52 from what they’re
0:30:53 doing, which is to
0:30:53 home in on these
0:30:54 low-fat, low-calorie
0:30:55 foods.
0:30:57 What’s amazing and
0:30:58 frankly also important
0:31:00 are these findings that
0:31:01 once you teach
0:31:02 anorexics what’s
0:31:03 happening to them,
0:31:04 that they’re doing
0:31:06 this, they are able
0:31:06 to intervene.
0:31:07 Now, they need
0:31:09 support, right?
0:31:10 And another form of
0:31:11 therapy that seems
0:31:12 to work well for
0:31:14 anorexics that ideally
0:31:15 is combined with this
0:31:18 habit rewiring is a
0:31:19 family-based model.
0:31:21 Family-based models are
0:31:22 starting to surface a lot
0:31:23 now in various therapy
0:31:24 settings.
0:31:26 Therapy-based models in
0:31:27 short are basically
0:31:29 where the entire family
0:31:30 is made aware of the
0:31:31 individual’s challenges
0:31:32 with a particular eating
0:31:33 disorder or other
0:31:35 disorder and in
0:31:36 understanding some of
0:31:36 the biology and
0:31:37 psychology around it,
0:31:39 they stop condemning
0:31:40 the individual, they
0:31:41 start to support that
0:31:42 individual through
0:31:44 queuing them towards
0:31:45 their own habits that
0:31:46 they observe, they
0:31:46 give them some
0:31:47 autonomy, they realize
0:31:48 that none of this
0:31:49 changes overnight, but
0:31:50 they’re taught about
0:31:50 things like
0:31:51 neuroplasticity and
0:31:52 the ability to change
0:31:53 one’s brain in response
0:31:54 to experience.
0:31:55 And so there’s a whole
0:31:57 internal support network.
0:31:58 All of these things
0:31:59 fall under the umbrella
0:32:01 of cognitive behavioral
0:32:02 therapy, and I should
0:32:02 mention that cognitive
0:32:03 behavioral therapies
0:32:05 are often done in
0:32:06 conjunction with
0:32:07 pharmacologic therapies.
0:32:09 before we move on to
0:32:10 talking about bulimia and
0:32:11 some related disorders, I
0:32:12 want to talk about an
0:32:13 aspect of anorexia that’s
0:32:15 very interesting, quite
0:32:17 troubling, in fact, but
0:32:18 that has received a lot of
0:32:21 attention, and that’s the
0:32:23 distorted self-image.
0:32:26 Now, in the episode on
0:32:27 depression, we talked about
0:32:30 a very powerful aspect of
0:32:32 major depression, which is
0:32:33 this anti-self-confabulation
0:32:34 that people who are depressed
0:32:37 seem to genuinely believe
0:32:38 and even confabulate about
0:32:39 the fact that they are
0:32:41 performing poorly in life and
0:32:42 that they are no good or
0:32:43 worthless, et cetera.
0:32:45 It’s literally a lie that
0:32:47 they believe, and their
0:32:48 statements and their
0:32:49 feelings and their behaviors
0:32:51 start to reflect that lie.
0:32:52 They’re not conscious of it.
0:32:53 That’s why we call it a
0:32:54 confabulation.
0:32:58 Anorexics often will see
0:33:00 themselves as overweight or
0:33:02 imperfect in ways that are
0:33:04 of an obsession for them.
0:33:04 In the case of the
0:33:06 anorexic, the problem seems
0:33:08 to be that they have a
0:33:11 genuine distortion of their
0:33:13 self-image, so much so that
0:33:15 they don’t actually see
0:33:16 themselves accurately.
0:33:18 Their visual perceptions are
0:33:20 off, and the reason we know
0:33:21 this is because of some
0:33:22 really important and
0:33:23 beautiful studies that were
0:33:25 done in my colleague Jeremy
0:33:27 Balenson’s lab at Stanford.
0:33:28 What’s really interesting
0:33:29 about these studies is they
0:33:30 give us a window into the
0:33:32 perceptual defect that
0:33:33 anorexics have.
0:33:34 I’ve actually done one of
0:33:35 these experiments.
0:33:36 I’m fortunate to not be
0:33:38 anorexic, but I’ve done some
0:33:39 work with the VR lab over
0:33:40 there, and what you get to
0:33:41 do is you get to adjust this
0:33:43 avatar of yourself to the
0:33:44 point where you think it’s as
0:33:46 accurate as it could possibly
0:33:48 be, and anorexics really
0:33:50 distort this avatar.
0:33:52 In other words, they create
0:33:54 this serious mismatch between
0:33:55 their perception of
0:33:56 themselves and the reality.
0:33:58 So, indeed, it does seem to
0:33:58 be the case.
0:34:01 Now, what’s relieving, or I
0:34:02 should say, what’s encouraging
0:34:05 about some of the therapies that
0:34:06 we talked about before, the
0:34:08 family-based model, the cognitive
0:34:10 behavioral treatments, yes, and the
0:34:12 drug treatments as well, but this
0:34:15 habit intervention model is that as
0:34:18 one starts to shift those things, it
0:34:19 does appear that the perception of
0:34:22 self seems to follow, that the
0:34:24 perception of self seems to shift
0:34:26 along with the change in habits.
0:34:28 So it doesn’t seem that trying to
0:34:29 tell someone, oh my gosh, you’re so
0:34:31 thin, you really need to eat, that
0:34:32 doesn’t seem to work.
0:34:35 They just don’t see themselves the
0:34:36 same way that you see them.
0:34:39 And so I offer that as a point of
0:34:40 consideration if you know someone
0:34:42 that’s anorexic or if you look at an
0:34:43 anorexic and you think, how is it
0:34:45 that they are still critical of the
0:34:48 small, even non-existent amount of
0:34:49 body fat on their triceps or
0:34:50 something?
0:34:51 How is that?
0:34:52 Well, it’s literally that their
0:34:54 brain, as it relates to perceptions,
0:34:56 visual perceptions in particular,
0:34:58 they’re completely off.
0:35:00 And fortunately by changing habits, you
0:35:01 rewire those circuits as well.
0:35:04 I’d like to take a quick break and
0:35:05 acknowledge one of our sponsors,
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0:36:45 Okay, so let’s talk about bulimia, which
0:36:49 is overeating and then purging, typically
0:36:52 by self-induced vomiting or by ingestion
0:36:53 of laxatives.
0:36:54 And then we’ll also talk about binge
0:36:56 eating disorder, which has a lot of
0:36:59 the same features as bulimia, but
0:37:00 typically no purging.
0:37:02 The criteria that were described to
0:37:05 me is that if somebody is doing this at
0:37:07 least once a month over a period of
0:37:08 anywhere from two to three months, then
0:37:10 one, it likely would qualify.
0:37:12 They’re not making the decision to
0:37:13 overeat.
0:37:16 They are driven from the inside to
0:37:19 ingest far more food than they need.
0:37:21 And in some cases than they would want
0:37:21 to eat.
0:37:24 So it’s a lot like the habit that we
0:37:26 described for anorexia.
0:37:28 It’s almost like it’s turned into a
0:37:29 reflex once they get going.
0:37:32 All the homeostatic signals are being
0:37:33 overridden.
0:37:35 All the signals from the body, the
0:37:38 leptin, the insulin, the glucose, all
0:37:40 that stuff is cosmically sky high.
0:37:42 And yet they’re just what we, you
0:37:45 know, the nerds call hyperphagic.
0:37:46 They’re just eating like crazy.
0:37:49 There’s a lot of shame associated with
0:37:53 bulimia, oftentimes because people are
0:37:55 vomiting and it’s hard to hide that
0:37:56 vomiting behavior.
0:37:58 People are aware of it.
0:38:00 The hallmark feature of bulimia that
0:38:03 distinguishes it from anorexia, aside
0:38:04 from the fact that it’s overeating as
0:38:06 opposed to under eating, is a lack of
0:38:08 what they call inhibitory control.
0:38:10 And that might come as no surprise.
0:38:15 But first of all, the bulimic, unlike the
0:38:21 anorexic is hyper impulsive and oftentimes has
0:38:22 other types of impulse behaviors.
0:38:25 And for that reason, many of the treatments
0:38:26 that you see for bulimia and binge eating
0:38:29 disorder are the sorts of treatments that
0:38:32 don’t seem to work so well, or at least most of
0:38:33 the time for anorexia.
0:38:36 So the drugs that increase the neuromodulator
0:38:41 serotonin, for instance, fluoxetine, also called
0:38:45 Prozac, Paxil, et cetera, those things oftentimes can be
0:38:47 effective in bulimia.
0:38:49 Some of the drugs that are used to treat attention
0:38:52 deficit hyperactivity disorder and ADD, some of those
0:38:56 same drugs like Adderall, Vyvanse, and things of that sort
0:39:01 can also be used to treat bulimia and binge eating disorder.
0:39:02 Why would that work?
0:39:05 Well, now you are familiar with the prefrontal cortex.
0:39:08 Prefrontal cortex is involved in this analysis of duration,
0:39:09 path, and outcome.
0:39:13 Duration, path, and outcome is how we avoid impulsivity.
0:39:15 It’s how we think, okay, if this, then that, if that,
0:39:18 then this, you can imagine how for the obsessive compulsive
0:39:22 or for the anorexic, these are circuits that are overactive.
0:39:26 For the bulimic, this is the circuit that’s going to
0:39:27 essentially be underactive.
0:39:30 So really the polar opposite of what you see in anorexia.
0:39:35 So this lack of impulsivity implies a lack of prefrontal
0:39:37 control, what we call top-down control.
0:39:38 They become more impulsive.
0:39:45 So bulimics have an issue with impulsivity and therefore drugs
0:39:48 that can increase serotonin and sometimes these drugs that
0:39:52 increase dopamine and norepinephrine levels in the brain
0:39:54 allow for more top-down control.
0:39:57 And that’s also why they’re used to treat ADHD and attention
0:39:58 deficit disorder.
0:40:01 These drugs tend to create a hyper-focus and tend to push the
0:40:04 brain and general mode of processing into one in which you
0:40:06 think, if this, then that, if this, then that.
0:40:07 So anticipating outcomes.
0:40:10 Do behavioral interventions work for bulimia?
0:40:14 In some cases, yes, provided that those interventions are done
0:40:15 early enough.
0:40:20 Regardless, behavioral interventions coupled with drug-based
0:40:22 interventions are always more effective than either one alone.
0:40:27 Fortunately, there is a decent-sized kit of drugs that can help
0:40:27 with bulimia.
0:40:30 We have, on the one hand, anorexia, which seems to be a
0:40:35 disruption in habit and a coupling of unhealthy habits, in this
0:40:38 case, food restriction, to the reward pathway.
0:40:42 And on the flip side, we have binge eating disorder and bulimia,
0:40:46 where a very unhealthy habit of gorging oneself with food, sometimes
0:40:49 followed by purging, is not necessarily coupled to reward.
0:40:51 They feel terrible when they do that, right?
0:40:54 The anorexic feels great about restricting their food intake.
0:40:56 They feel like they’re winning some sort of game.
0:40:59 The circuitry is flipped somehow that way.
0:41:04 With bulimia, they feel horrible about the fact that they’re binging.
0:41:05 There’s immense shame.
0:41:07 They can’t control themselves.
0:41:10 The reward is set up before the behavior.
0:41:16 The reward is set up in drawing them to food and in making food look like
0:41:21 something that’s incredibly appetizing, and there’s no impulse break.
0:41:23 There’s no way for them to stop that kind of behavior.
0:41:27 I think for those of us that know anorexics or have observed anorexia,
0:41:31 it’s so hard to see somebody starve themselves to near death or to death.
0:41:36 Equally disturbing is somebody who has an abundance of food and is gorging
0:41:38 themselves and then feels terrible about it.
0:41:41 So these are heavy topics.
0:41:47 These are topics that, frankly, no one really wants to talk about unless they know
0:41:49 someone who’s suffering from them or they themselves suffer from them.
0:41:55 What I’ve tried to do today is try and give you a window into what really underlies these
0:41:57 things that we call eating disorders.
0:42:03 I hope I’ve done that at the level of biology, neurocircuitry, mechanism, endocrinology, and
0:42:04 some of the psychology.
0:42:10 As with any episode of this podcast, but especially where we’re talking about mental health issues
0:42:15 and mental health disorders, behavioral disorders, there’s no way that I can exhaustively cover
0:42:17 all the different forms of treatment.
0:42:21 The major takeaways today are we should all be asking the question, what is healthy eating
0:42:22 for us?
0:42:28 How do we develop a relationship to food that we can enjoy food, hopefully both socially and
0:42:32 on our own, but that we are not neurotic and compulsive about it?
0:42:39 Today, we focused on the extremes of food-related behaviors that really qualify as genuine disorders.
0:42:47 They are in the psychiatric manuals and they are diagnosable and they are serious health concerns.
0:42:51 They’re not just mentally troubling and concerning for the people suffering from them and the people
0:42:53 around them, but they are genuine health concerns.
0:43:01 Just want to reiterate that anorexia nervosa is the most deadly psychiatric disorder by a huge margin.
0:43:06 And if you look statistically at the number of people with eating disorders and that die
0:43:11 of eating disorders, it’s not far off from the number of people that die from automobile accidents.
0:43:17 I would love for you to take away this model that was handed off to me that I think is so powerful
0:43:21 for thinking about all sorts of things, not just eating, but all kinds of behaviors and perceptions
0:43:28 that you have one box for what you think, one box for what you do, and what is intervening
0:43:28 between those?
0:43:31 Why is it that you can know better and not do better?
0:43:37 Well, it’s because you also have to cope with the subconscious homeostatic processes and reward
0:43:38 processes.
0:43:45 And those oftentimes can be disrupted in ways that we find ourselves doing things that are
0:43:46 not good for us or not good for other people.
0:43:52 But fortunately, there is this great gift, which is that knowledge of knowledge can allow
0:43:59 you to do better without question, and that knowledge of knowledge allowing you to do better
0:44:04 over time leads to this incredible phenomenon called neuroplasticity, which essentially is translated
0:44:09 into doing better over time, even if difficult, eventually makes doing better reflexive.
0:44:15 And last but not least, I want to thank you for your time and attention, and thank you for
0:44:16 your interest in science.
0:44:25 And as mentioned at the beginning of today’s episode, we are now partnered with Momentus
0:44:29 supplements because they make single ingredient formulations that are of the absolute highest
0:44:31 quality, and they ship international.
0:44:36 If you go to livemomentus.com slash Huberman, you will find many of the supplements that have
0:44:40 been discussed on various episodes of the Huberman Lab podcast, and you will find various protocols
0:44:41 related to those supplements.