In this episode, we talk about the difference between somatic hunger and limbic hunger, and what it feels like to reach appetite correction through Fast-5 and intermittent fasting. 

02:30: Types of hunger: limbic, somatic, clock-driven, and appetite-driven
16:28: Am I hypoglycemic? Understanding glucose levels
21:45: Recognizing that fat is fuel
24:12: Your Goal Body
31:00: Managing stress
31:14: If I’ve never done intermittent fasting, am I going to be fighting hunger?

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Podcast Transcript

Judi: Hello! And welcome to the D.I.E.T. podcast, where we explore an important question for those who are pursuing a whole, healthy and happy life. And that question is “Did I enrich today?” I’m Judi.

Allison: I’m Allison.

Bert: And I’m Bert.  

Judi: We’re your hosts, and today we’ll be discussing one of the fears that people have as they consider whether an intermittent fasting lifestyle might be a good fit for them: The fear of being hungry. We’re delighted that you’re joining us here today and really hope that you enjoy the conversation. To start out today’s discussion, Allison, I’d like for you to speculate about something. We’ve heard people express concern that if they adopt an intermittent fasting lifestyle, they’re going to be hungry all the time. Now with that perception out there, the question I have is: “How has intermittent fasting become so popular?”

Allison: Well, I think there might be a few reasons for that, Judi. I think one reason is that we see so many celebrities talking about intermittent fasting right now. From the Kardashians and Jennifer Aniston to Chris Pratt and Halle Berry, and even Hugh Jackman—they’re doing intermittent fasting. They’re talking about it and people are seeing results in the media. So people on Instagram and YouTube are watching these people and saying ‘Well, you know, how hard can that be?” So, a lot of people are trying. I think I’ll also, there are a lot of people that are afraid of the feeling of hunger and they might not have ever actually really felt hunger in their life. And I’m not talking about people that are experiencing food insecurity. I’m talking about people that are used to eating three meals a day—to take two of those meals out, or to have a fasting period of 12 or more hours—that might be really scary for some people.

Judi: I was just thinking as you were talking about celebrities who adopt this lifestyle, or who have adopted this lifestyle—that can feel

inaccessible. Like, if I’m someone who is well-known and well-funded, then it will be easier for me to do this because I have a whole support network. So, this isn’t really available to the every-person out there. The every-person, well, they’re not going to have someone cheering them on when they feel a little bit of hunger, so maybe it’s just not for them. The three of us have been in touch with people across the world—thousands of people—

Allison: Mm-hmm.

Judi: —and in our conversations, we talk about hunger. There’s not just one hunger in this world. There are varieties of hunger. It’s like the snow. In some regions of the world, there are many, many, many words to describe the various types of snow, but where I have been living most of my life, there’s one word: snow.

And I think the same goes for hunger. There are a lot of ways to describe hunger, because there are different sensations of hunger, but we only have this one word. And so, Bert, you wrote about this in The Fast-5 Diet and the Fast-5 Lifestyle, that was published

back in 2005. Can you talk about that a little bit?

Bert: Sure. The first book, the Fast-5 book, talked about somatic hunger and the appetite driven hunger as different things, and they are different things. Somatic hunger refers to the feeling that you have in your belly when you are hungry and you have some cramping sensation and you kind of notice that you’re hungry. That sensation is often just driven by your schedule. It happens at the same time every day, and kind of reminds you to eat. The other kind of hunger that’s mentioned in the Fast-5 book is limbic hunger, which means that when you start to eat something, it kind of opens the door for lots more eating, and you eat until you’re full, no matter what.

The AC book talks about more nuances about that, including the appetite driven

hunger. When you eat and you’re not feeling any pain or cramps or any sensation in your belly, but you still feel compelled to eat, and you don’t really know why you’re eating—you’d rather not eat, but you keep eating, that’s appetite-driven hunger. And so, we have at least three kinds of hunger that are driving intake. The somatic hunger may be the easiest to deal with because it doesn’t really mean anything is happening except the clock strikes whatever time you usually eat and your body is used to eating then, and it says “Well, where’s the food?” That’s fairly easy to distract from and ignore.

The others are more difficult to get in control because they’re driven from the core of our brains. The limbic hunger says “Well, you’ve got some food, and we don’t know when the next meal is, so you’d better eat all you can now!” Limbic hunger drives us to start eating our

fill as soon as food is available. Appetite-driven eating compels us to eat—it comes from the brain core, so it’s very difficult to suppress, but when we see ourselves going through the motions of eating—we’re putting food in our mouths, and we don’t really know why and we would rather not be taking on those calories—that’s appetite-driven eating.

Allison: Mm-hmm.

Judi: One of the things that I was thinking about as you were talking about that, Bert, is that limbic hunger is an important survival hunger. In the days when food was scarce, and then food became available, limbic hunger compelled one to eat so much that they could store fuel in what you have often described as nature’s refrigerator.

Bert: Right.

Judi: So, instead of food being available to bugs or bacteria or whatever—or other animals, or other humans—in order to keep that food preserved, eating

more than the body needed at that exact moment in order to function helped humans to survive to the next availability of food. So, let’s say you wake up in the morning, you need to hunt or scavenge. And we’re talking back in primitive days when survival was very dependent on acquiring resources to survive.

Bert: Mm-hmm.

Judi: And then, a successful hunt or a successful harvest—I don’t mean the harvesting like modern agricultural harvesting, I mean like finding some berries here or there. If it’s not gonna be around in two days, then it makes perfect sense to gobble up everything that you can in order to have that extra fuel on your body, where it’s free of the risk of going to waste. Spoiling.

Bert: It does! We follow the same logic when we fill up our cars with gas. We don’t just fill up, typically, with enough gas to get to the next destination, or even the next couple of destinations. We fill up with enough

to fill our tanks. And so, we know that that’s going to provide enough fuel to get us to a lot of places and those places, eventually, will include the next gas station, where we will fill up again. When we stop for food— in the ancient times, with the influence of appetite, we’ve evolved to fill up with as much as we can when the opportunity to eat is a good one. We typically fill up the refrigerator—meaning our fat stores—as much as we can when the eating is available.

Judi: So, what helped us survive in times past—limbic hunger was very, very powerful survival tool, but in a world that has an abundance of food available, it becomes something that is not necessarily to our advantage. As I have the concept in my head, that’s where broken appestats happen.

Allison: Something

that has helped me in the past, when I have been ramping back up into IF is I ask myself when I have that…Sometimes stressors really just kind of trigger “Okay. I just…I’m just going to get a snack. I’m just gonna eat something really quick while I think about this, but then I ask myself  “Am I hungry?” and I take a minute and I just feel my body. Am I actually feeling hungry? And the answer is always “No!” You know, I’m not really hungry! My stomach’s not growling. There’s no reason, really, to eat other than just kind of taking myself out of a stressful situation. So that might help people—just ask themselves that question: “Am I hungry right now?”

Bert: Yes, it can be very frustrating to see your body do things that you don’t really control, but we have to accept that that happens and work to modify those actions. I’ve been there. I have seen myself with plenty of fuel on

board, stored in the form of fat, and I just can’t stop eating whatever it is I started to eat. I ask myself “What’s going on here?” And what’s going on is that the ancient survival skills that our bodies learned from years past basically say “Eat when you can!” That’s better than eating too little, because eating too little meant you died, and eating a little extra was no big deal. The survival skills are still with us, and in a time when there’s plenty of fuel or food—same thing—available. It means that we pack on too much.

Judi: Yeah. One of the thoughts that I had was…because hunger—the term hunger, the concept of hunger is so nonspecific, it can mean that the body needs fuel because it’s under-fueled. It can mean—I’ll tell the tale on Bert. He had a cup of coffee that had caffeine in it. That caffeine

started making gurgling sounds in his belly. I could hear them. And so, that was not an indication that his body needed fuel. It was an indication that his body had just received, frankly, a drug, or at least a…a physiologic modulator in the form of caffeine. So, given that there are these various types of hunger, and hunger doesn’t necessarily function as a very good guide for what our body is needing when we have plenty of fuel in the form of stored fat, maybe a question to ask is not “Am I really hungry?” but “What does my body need?” Sometimes, when I’m really stressed, what my body needs is stress relief.

Allison: Mm-hmm.

Judi: I think looking at “What is my body telling me?” and “What is the need that it is expressing?”— almost having that conversation with oneself, without making yourself crazy, can be helpful rather than just “Am I hungry?”

Allison: Mm-hmm.

Bert: When we’re hungry,

that can be clock hunger, which is your body reminding you that you ate this time yesterday: “Where’s the food today?” And, it would be nice if we could just ignore that, but nature has made it very difficult to ignore.

Judi: So the body is a food storage machine. It’s a survival machine.

Bert: Sure.

Judi: And, part of surviving in the scarcity of food is to be able to store it, and then, when we don’t have a scarcity of food that survival mechanism has to be something that we work with. We have to work with our body, and that’s where appetite correction comes in. It lets the body recalibrate what it needs so that it’s not these various forms of hunger that are the only impulse that gives us guidance as to what it needs.

Bert: Right.

Judi: Does that make sense?

Bert: Yes, we can’t beat it directly, like we can’t just choose to stop breathing. So, we have to find ways to work around it. An intermittent fasting schedule that gets us to

appetite correction is that kind of tool that gets us around it and finds a way to leverage our primitive brain with our more conscious brain that says “This is really okay. I’m going to do this and it’s okay and it’s healthy and we’re going to get to our goal weight this way.” And, that has to balance out with the primitive brain that says, “You gotta eat.”

Allison: Mm-hmm.

Judi: So we’re coming full circle a little bit. The question that we started with was, “Not knowing this lifestyle, if I take on an intermittent fasting lifestyle, am I going to be…hungry? Am I going to be fighting that hunger?” That’s the question, “Do I have to have a big celebrity-style network around me to help me white-knuckle through that hunger that I’m going to use my willpower to get through?”

Bert: That’s a good point and the white knuckles are basically the reason that we started working on Fast-5 and spreading the word. This was a way to get to the goal body that we all wanted without

having to fight hunger all day. You’re not hungry. The appetite corrects itself when it’s given the chance and we’re not hungry. We’re not wanting extra food. That’s the big key: appetite correction. If we have that, the rest gets easy.

Judi: And the way to appetite correction is what? I mean, Allison are you hungry when you do—when you are living an intermittent fasting lifestyle, do you find yourself fighting hunger?

Allison: I don’t. It’s a mind game. And when I say it’s a mind game, that’s when I’m going through the period of I haven’t been fasting and then I…I jump back into the lifestyle. And it’s usually just a couple days of “Okay, I remember what this is like, it’s just going to take a little bit of maneuvering.” I usually start with an eight-hour window and then I reduce that time to five, four, three hours. But I…no, I don’t feel hungry. I just have to remind myself: “We’re just going to wait a little bit longer to eat.”

Judi: From my experience, I have a clock hunger,

no question, that’s around noon, which is interesting because I have imprinting from when I was a kid. I ate around lunchtime every day, the typical midday lunch meal, but I haven’t done that in, 17, 18 years. So, why my body somehow, around noon, tells me it wants a meal, I don’t know, but it does. I feel this little bit of a…twinge that reminds me that I live this lifestyle because I feel it. And then, I wait literally minutes.

Allison: Mm-hmm.

Judi: I wait five minutes, ten minutes. I don’t think it’s ever taken 15 minutes, for that matter. But if I ignore it ever so briefly, it simply goes away. This is a little bit of a weird analogy, but I’m going to just use it. My background is as a urologist, so I’ve spent a lot of time with the urinary system.

The bladder works as a storage vessel for urine. It empties, you know, we head to the toilet, we empty our bladder and then it fills. It fills to about 300 cc and then we empty it again. Now it can go up to 500,

but usually, around 300 or so, we’re feeling interest in going to the restroom. Yet, if it’s a socially inappropriate time, like you’re driving in your car, one doesn’t just empty their bladder—they wait and get to a gas station or to their destination. That doesn’t damage the body. That’s just the one of those cycles that the body has. So, what I have often thought about when the noontime hunger comes around is, I wait for a few minutes and it goes away. It’s just that same thing. I’m not compelled the minute that I feel hunger to address it. I can let my body do what it naturally does, but we have to give it time to do that. We started out talking a little bit about popular culture and the influencers. Among the influencers out there are those who stand to gain a whole lot by us eating a lot. I see commercials that address things like “hangry,”

Allison: Yeah.

Judi: —like “I have hunger and that makes me behave badly.” I’ve seen candy

bars with words on them, like this is the antidote to boredom or this is the antidote to being angry or sleepy. That kind of messaging is so inaccurate—

Allison: Mm-hmm.

Judi: —that it makes me a tiny bit nuts.

Bert: Right. Little do people know that if they just choose not to eat for the entire fasting period they choose, they will not be hangry. They won’t be grouchy. It just takes a few days to adapt to.

Allison: Dr. Bert, one thing I want to ask you, I hear a lot. People say “I can’t skip a meal. I’m hypoglycemic and I’ll faint.” What do you say to those people?

Bert: For those people, I say that the approach I would take is to get a glucometer, which is a blood glucose measuring device that diabetics use. I would check to see whether my blood glucose was really low during the times when I felt low after eating. If it was truly low,

I would go to my doctor and say “I really get a low blood glucose after eating, what’s going on? This doesn’t seem normal.” But if I found that there was a normal level of glucose, I would understand that what I’m feeling is really a genuine feeling, but it does not have to do with my blood glucose.

That has happened in so many people that there’s a term for it in the medical world called non-hypoglycemia, which just means you have the sensations of hypoglycemia, but you don’t really have a low blood sugar. In short, it means you can power on. You can keep going. It means that your hormones have made you feel this way, and if you keep going, your body will adjust to it and you won’t have this feeling anymore. So, there’s hypoglycemia, which is a real problem—

Judi: And unusual, right?

Bert: Right. It is pretty scarce.

You may have heard about it a lot, because a lot of people do have that sensation, but the number of people who truly have low blood glucose at the time that they’re having that feeling is quite low. If they do have that feeling, and their blood close blood glucose is truly low, they do need to see a doctor because there are some very serious problems that can cause it. If they don’t have a low blood glucose at the time, then they can just power on, let their bodies adapt and get to a healthier way of eating that lets them go more than a few hours without eating.

Allison: It’s really all part of the study of one, right? Feeling the sensations and studying your body and your reactions to certain things and going to your doctor and seeing what the labs really say and putting all that information together and figuring out what’s best for you, as an individual.

Bert: Right.

Judi: It is.

Bert: The Study of One recognizes that we are very complex creatures—

each of us has a different set of microbes growing in our gut that means that we each digest a meal in different ways. Even twins, who are side by side in the same environment, could have different experiences as they grow up and grow old. We have to be very cautious when some one-size-fits-all approach comes out that suggests that we could just do this and be healthy. The likelihood that that would apply to everybody is virtually zero. We have to work as individuals to find what’s right for ourselves and that means experimenting a little bit to see what works best for us.

Judi: This is probably a good place for us to say that, of the three of us, two of us are doctors, but we are not giving medical advice. What we are—

Allison: By the way, I’m not one of the doctors. I don’t know if you’ve noticed yet, but I’m not a doctor.

Judi: You’re so funny, Allison.

Anyway, what we are doing here—we’re having a conversation. We’re inviting you to think and to work with your doctor to conduct your own Study of One. Bert, you mentioned that one of the ways to see if you have hypoglycemia is to test your blood sugar. If I test my blood sugar, what number would worry me and have me go to my doctor?

Bert: In the US, the typical number that would cause concern is below 75 milligrams per deciliter. So, if you get a glucometer and it reads less than 75, then there’s maybe some cause for concern, particularly if it’s lower than 70. If it’s higher than 70, then that suggests that what you’re feeling, no matter how real it is, is not being caused by a low blood sugar. That’s the key. The feeling is real. A lot of people have it, but it is not necessarily caused by a low blood sugar. There are

Judi: It’s interesting. One of the things we’ve talked about in the past is that fat, which we all have and need, elaborates over 40 hormones. If one has an abundance of fat, the amount of tissue that can elaborate those hormones is quite significant. Our bodies are very complex, and there are so many moving parts, and so many modulators of those moving parts, that to imagine that everything comes down to a glucose that is up, or glucose that is down, or glucose that is changing, it serves

Allison: Right! They market it as energy. Glucose is energy! Have the energy to do the things that you want to do! Meanwhile you know, I’ve got like 20-30 extra pounds hanging around! Like, what am I gonna do with that stuff? I’ve got all this energy that’s just waiting to be expended!

Bert: That’s a big key—we have to recognize that fat is fuel and when fat accumulates, it can easily become the largest organ in the body, and that’s not widely recognized.

Allison: Wait, what?

Bert: Yeah.

Allison: Could you repeat that Bert? I’m sorry. That’s something I’ve never heard before and it makes me nervous.

Bert: Usually the skin is recognized as the largest organ in the body, but that means

that the person is relatively lean. When their body weight gets to be 20 to 30 to 40 percent higher—sometimes even double, then fat really has become the dominant organ in the body by weight. It can control what we do and disorder every other function. Our brains are only about three pounds, so if we have 30, 40, 50 pounds of fat—maybe a hundred pounds?—that organ can make lots of hormones that basically say “Feed me!” and it’s sometimes takes some special tools to fight against that.

Allison: Wow, you just blew my mind! That’s pretty cool.

Judi: What’s really cool about it too is that we have interacted with a lot of people for whom there was a time in their life when it was the biggest organ in their body. And, through an intermittent fasting lifestyle—the Fast-5 lifestyle—there is a pathway to regaining the control without being hungry.

Allison: Mm-hmm. That makes sense.

Judi: I like the idea that life is dynamic and if we’re living a full and rich life, there are times that we expand our window and we take on a little extra fuel—I like having the tool that reliably lets me get things proportioned again, to the goal body. Bert, you mentioned the goal body. Can you talk a little bit more about that?

Bert: Sure. The goal body is basically how we see our ideal body shape. What we what we would like to see in a mirror when we look at it, standing in the nude in the bathroom or whatever. That’s our goal body. I refer to goal body because a lot of people look at the scale as their guide to whether what they’re doing is working or not. But the goal body is what they really want. They don’t want to a particular number on the scale. I don’t look at the scale and say oh, I wish I were this

digits. I look at my body and say oh I’d like for it to look like this, or I want that curve to go away or I want to be back where my body looked like a was in college. So, we’re talking about a goal body, not a goal weight.

The scale is so subject to changes in water volume in our bodies that it can be very misleading and very discouraging. You can do something that’s very successful in losing weight, and then you have something like a meal that has a lot of salt in it, you drink a couple of glasses of water. All of a sudden you’ve gained a pound or two pounds—or in some people, it may be five pounds! And you go, “Oh my God, this is not working for me!”

Allison: All that work for nothing!

Bert: Right. When the truth is that your body has actually lost fat, but gained water. And so, I want to focus on the goal body, not the goal weight. Not a number on the scale, but how you look,

how you feel about how you look and how you get there.

Judi: The interesting thing about weight is it’s a relationship with our planet. It’s gravity. It’s pulling us down. And so, the same body, say you go to the Moon, your weight is going to be different. I haven’t seen any shuttles to the Moon of late, so I’m not thinking that that’s what we’re really going to do, but I mean just theoretically, that scale is relative to something outside of one. But the goal body, that allows us to connect with the goal—what is in our mind’s eye, what’s in our aspiration. And, a goal body, may be a body that can climb a mountain. A goal body may be a body that can ride a bicycle, or it can dance like one danced when they were 20 or something. The metric for what that goal body looks like is so much more tangible, and so much more active than just this number on a scale that is so affected by things outside of that body.

Allison: Mm-hmm.

Bert: Right.

Allison: So, Judi, tell us a little bit about what your goal body is.

Judi: Okay. I actually have a relationship with my goal body that is pragmatic and aspirational. Today, I am not at my goal body. There’s no question. We’re in the middle of the holidays and my goal body is waiting for me when I am back in my own environment, and in my own routine. And I know, about two weeks from now, I’ll be feeling the way I really like feeling. My usual body is not quite my goal body, but it’s my comfortable body.

When I was out doing the walk with Gary Long, back in 2006, I was not with the usual food source, and so I didn’t have the relationship with food that I have right now. Right now, if I want to get something to eat, I go to the refrigerator and I get something to eat. Back then, we hauled our food with us, like when you’re hiking. You don’t have just this abundance of many, many, many options. And so, I ended up dropping my weight by probably ten pounds and

it felt really good. It was fun. It was nice. And if I had a job that let me be in that environment often, I would probably find myself being just delighted as could be to be at that goal body.

That said, it’s not worth it to me to create that relationship artificially with availability of food, and instead, in the D.I.E.T. world, the “Did I Enrich Today?” way of daily life, there’s no question that being able to have a glass of wine with friends is enjoyable to me. And if that means I carry five extra pounds over what I would have on my body when I’m out hiking, I’m good with that. That goal is the fully-enriched-and-immersed-in-community body. Then, sometimes it’s kind of fun to go out and do a hike somewhere and feel my hiking body.  I have a body that

is adaptive and morphs—so I have a contextual body. How’s that?

Allison: I Iove it.

Judi: Kind of funny—Think about it. During pregnancy, that body looks like a very dif—you know, contextually, it’s this…it’s the goal body because it has this big bump in the middle of it, you know, which…

Bert: Mm-hmm.

Judi: …if one weren’t pregnant, would certainly not have been my goal body.

Bert: Right.

Judi: …but given the context that there was a living creature inside of me, it made sense!

Bert: Another body in the body.

Judi: Another body in the body. I had a goal body in the body.

Bert: Right.

Judi: Yeah. What about what about you, Allison?

Allison: Well, I can say that right now, I am not at my goal body, but I try to not beat myself up about it at every moment of every day, because it just…it is a…it really weighs me down. Sorry for the pun. But I do…my goal body is a body that doesn’t have…

This is going to sound funny but, doesn’t have a bunch of useless fat hanging off of it! I want to be able to…to move easily and not feel like…just kind of trapped inside of all of this extra fluff. But, I know I’m going to get there and I know how I’m going to do it, and it’s just a matter of every minute of every day just living through to…you know, get to the…the goal point. It’s not going to be fast. I know that and that’s fine. But, you know, I have some family members that are getting older and having a tougher time, and a few of them are heavy. And, it just makes life so much more difficult. So, I really just want to take good care of myself so that as I age, I can continue to keep up with

other people and friends and the community.

Bert: That goes full-circle back to what we were just talking about on our live Facebook video in terms of how do you manage stress? We know stress is a big deal. It drives appetite. So, what do you do with it? And we had a little session about that. It means, in part, taking care of yourself. Looking to yourself. What are your needs? What do you need to do to keep the stress on the outside of your head, your mind, your body, so that it doesn’t get in and change your choices—change the way you behave, and change your efforts in the direction of your goal body, or your maintenance of that goal body.

Judi: So, we’ve talked about hunger and I think before we end this episode, let’s answer, like really concretely, the question of “If I’ve never done intermittent fasting, and I’m considering, right now, doing intermittent fasting,

am I going to be fighting hunger?

Allison: My answer to them is “Heck, no, you’re not! But, it just takes a couple days. If you can get past the first few days and not be afraid of hunger, you can absolutely do this. And, it’s comfortable, and it’s easy, and it’s not weird.”

Bert: And, I would say the first few days that Allison mentioned—that’s the key. If you know that beyond that first few days, there’s this wonderful pathway that’s smooth sailing and very comfortable and works for you, then you can get through those first few days. But, if you don’t know that, those first few days can be enough to say “Wow, there’s no way that I’m getting through this,” and so we’re back to the sandy hill. You have to you have to adjust you have to give your body time to adjust and you have to be okay with slipping a little bit. Your body is not going to deliver that kind of performance until you

ask for it. So ask for it. Ask for it again. Ask for it until your body complies and you’re on your way.

Allison: Bert, I love that. I’m going to ask my body for some things today, and I’m hoping that it will comply.

Judi: I love that too. That’s great. That’s it for today’s episode of the D.I.E.T. podcast. And since we’re asking our body for things, then I’m going to make a suggestion and that is: The next time that you’re in the grocery aisle, or you’re checking out at some store and you see a tabloid that has the word diet—D-I-E-T, not with periods, on it, ask yourself the question that we’re exploring in this podcast: “Did I enrich today?” Thanks for listening!

Allison: And

don’t forget to visit DidIEnichToday.com for more information about intermittent fasting. And, if you like listening to audio, you might enjoy the AC: The Power of Appetite Correction on Audible. Don’t forget to subscribe to the newsletter. We’ll let you know about upcoming events and when new episodes are available. We promise not to spam.

Judi: Also leave us a note. Tell us what you’d like to hear on the next episode.

Allison: Thank you!

Judi: Bye.

Bert: Bye-bye!