What It Really Means to Regulate Your Nervous System—and How to Start

If you’re doing everything “right”—eating well, taking supplements, working on your health—but still feel stuck, this might be the missing piece. Your body cannot heal if it thinks it’s under threat. In this episode, we unpack why your nervous system may be the hidden driver behind inflammation, hormone imbalance, weight gain, and more—and how to finally shift your body into healing mode. Here’s what could be keeping you stuck: • Why chronic stress and nervous system dysregulation can block healing—even when everything else is “on point” • How your nervous system impacts your gut, hormones, metabolism, immune system, and weight • The difference between feeling “tired but wired” vs. true resilience and what a regulated system actually looks like • Simple, science-backed ways to regulate your nervous system through blood sugar, breath, sleep, and daily habits You can’t out-supplement or out-diet a body that feels unsafe. But when you learn how to regulate your nervous system, you unlock your body’s natural ability to repair, rebalance, and heal. Visit ⁠functionhealth.com for 160+ lab tests at just $365 a year. Have a question you’d love answered on Office Hours? Submit it here (0:00) Nervous system regulation, chronic stress, and healing (2:21) Simplifying the nervous system and resilience (4:06) Signs and effects of nervous system dysregulation (6:24) Characteristics of a regulated nervous system (7:39) Practical tips for nervous system regulation (10:09) Building muscle, improving sleep, and myths about regulation (12:20) Upcoming episode and sympathetic activation (14:09) Mitochondrial dysfunction and importance in health (18:37) Closing remarks and call to action

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

• 0:00Dr. Mark Hyman?

  So yes, nervous system regulation may be the missing piece because you can't out-supplement chronic stress signaling. You can't biohack your way out of a body that feels unsafe. Healing requires physiological safety.

• 0:27Dr. Mark Hyman?

  Welcome to Office Hours. This is our dedicated 101 space to go deeper, get clear, and explore what truly moves the needle for your health. I'm Dr. Mark Hyman, and each week, we're going to pull back the curtain and share the insights, the research, the lessons that don't always make it into our conversations with guests. Because at the end of the day, you are the CEO of your own health, and for many of you, your family's health too. And you might not feel it all the time, but you have far more power and agency than you realize. I'm glad you're here.

• 0:56Dr. Mark Hyman?

  This episode is brought to you by Function Health, empowering you to live 100 healthy years with over 160 lab tests for just $365 a year. And use the code MARK2026 to get $50 off your membership. Today, I want to talk about something that might be the missing link in your health. You clean up your diet, you're taking your supplements, you're trying to sleep more, maybe even run labs and to work with practitioners, or hopefully you've done your labs and go to functionhealth.com, make sure you get yours. But maybe you're still wired, or exhausted, or inflamed, or just stuck in your health. What if your issue isn't your gut, your hormones, or your metabolism? What if the real issue is your nervous system? Because here's the truth, your body cannot heal if it thinks it's under threat. So today, we're

• 1:39Dr. Mark Hyman?

  going to unpack what nervous system regulation actually means, and what a regulated nervous system looks like, and whether calming your internal stress response might be the key that unlocks healing. This isn't just about stress management, it's about biology. When I was in training to learn all about this stuff after medical school, because that was just the beginning, I took a course with a guy named Herbert Benson, and he said that stress either causes or worsens 95% of all illness. That's a big deal, and we should pay attention to that. In functional medicine, we talk a lot about inflammation. We talk about insulin, we talk about hormones, we talk about toxins. All important, but underneath all of it is one master regulator, your nervous system. So what is your nervous system really?

• 2:23Dr. Mark Hyman?

  Let's simplify this. You have two main branches of your nervous system. The sympathetic system, which is fight or flight, and the parasympathetic system, which is the rest, digestion, repair, the relaxation nervous system. The sympathetic system mobilizes you and it makes your heart rate go up. It raises your blood sugar. It redirects energy away from digestion and primes you for action, running from a tiger or getting in a fight. Not bad if you're surviving. It's essential. But the parasympathetic system is where healing happens. It's where digestion happens, where detoxification happens, where hormone regulation happens, where immune repair happens. And then there's the vagus nerve, which is a major communication highway between your brain and your body.

• 3:07Dr. Mark Hyman?

  It connects your brain to your gut, to your heart, to your lungs, to your immune system. So when we talk about nervous system regulation, we're really talking about your body's ability to shift fluidly between activation and recovery. The key word is how to be adaptable here or adaptability. Regulation doesn't mean being calm all the time. It means you can experience stress and then return to baseline. There's a great book called Why Zebras Don't Get Ulcers by Robert Sapolsky, who's one of the key scientists who's helped us understand stress. And the reason zebras don't get ulcers is because when the lion chases them, they run like hell, freaked out. The lion catches one of the zebras, then goes about eating it and all the other zebras

• 3:49Dr. Mark Hyman?

  just stop running and they stand around the lion while it's eating another zebra and they, their nervous system just calm right down. That's why they don't get ulcers. We just stay chronically stressed all the time. And the critical insight from functional medicine is this, your nervous system sets the tone for every other body system. So what is dysregulation of your nervous system actually look like? Well, most people don't realize they're dysregulated because it just feels normal. Let me paint you a picture. If you're chronically in sympathetic mode, that's sympathetic nervous system activation, stress response, you might experience a lot of things. You might feel tired but wired. You might be anxious and irritable. You might have digestive issues, constipation or diarrhea, irritable bowel syndrome. You might have blood sugar swings.

• 4:33Dr. Mark Hyman?

  You might get panic attacks. You might wake up at two or three in the morning. You might have belly fat that won't budge. Here's a little tip for you. Your nervous system is connected to your fat cells. And this is actually scientifically true. I've written about it in my books. The nervous system innervates fat cells or adipose tissue. And when you're stressed, it makes them get more fat. It makes you gain more weight. That's not a good thing. It also affects hormone swings, autoimmune players. We know that just actually regulating your vagus nerve, they can regulate their vagus nerve through various implantable devices now and cure rheumatoid arthritis.

• 5:18Dr. Mark Hyman?

  There was a study that I wrote about years ago where people who just journaled, who had rheumatoid arthritis for 20 minutes a day about their authentic feelings, had a dramatic reduction in symptoms, better than most medications. Also, chronic stress raises cortisol. It causes then elevations in blood sugar. Cause you know, when you're stressed, you want to have high blood sugar, but not all the time. And then when you have high blood sugar, you become insulin resistant. And when you become insulin resistant, that causes inflammation. Then when you have inflammation, that disrupts your hormones even more. It causes gut damage. It causes changes in your immune system. Now you're chasing symptoms. When the upstream driver is your stress signaling response. Now, on the other side, some people swing into what we call vagal shutdown. This is the freeze response. What does that look like?

• 6:03Dr. Mark Hyman?

  Well, fatigue, brain fog, low motivation, depression, feeling numb and disconnected. Many people bounce between both states, wired and exhausted at the same time. So tired and wired. It's not weakness. It's just nervous system dysregulation. So what does regulation actually look like? What does it look like to have a regulated nervous system? It's not constantly being calm. It's resilience. Now, regulated nervous system means you can handle stress without spiraling. You can digest your food well. You can sleep deeply. Your mood's relatively stable. Your heart rate variability improves. You recover faster from setbacks. Regulation is about recovery speed. It's about flexibility. It's about metabolic safety. Because your body feels safe. It turns on the repair system.

• 6:47Dr. Mark Hyman?

  When your body feels threatened, well, it prioritizes survival. And survival mode means shutting down long-term healing. Okay, so could this be the missing link to healing that we've been looking for? Well, let's connect the dots. If you're trying to heal your gut, but you're chronically stressed, well, your microbiome shifts in response to the stress hormones. So you literally change your microbiome with stress. If you're trying to balance hormones, but cortisol is elevated, it steals from the progesterone and other pathways that regulate your sex hormones. You're trying to lose weight and you're in constant fight or flight? Well, your insulin stays high. If you're dealing with autoimmunity, well, stress directly affects the immune signaling and your immune system's health.

• 7:29Dr. Mark Hyman?

  So yes, nervous system regulation may be the missing piece. Because you can't out-supplement chronic stress signaling. You can't biohack your way out of a body that feels unsafe. Healing requires physiological safety. How you regulate your nervous system? Let's make this practical. Number one, stabilize your blood sugar. Unstable blood sugar is interpreted as a threat. And let me tell you how to do that. Start your day with protein, really important. Balance every meal with protein, healthy fat and fiber. Reduce, or I don't even like the word reduce. I would just say never eat ultra-processed food. There's no reason to eat Twinkies or Pop-Tarts or Lunchables or Gogurts or any of the million things that are in the grocery store shelves that are not actually food. Just eat food. Listen to Mike Tyson, eat real food.

• 8:12Dr. Mark Hyman?

  This alone dramatically calms your stress signaling. Next, use your breath. One of the fastest ways to shift into the relaxation response to the parasympathetic mode is your breath. So you can try this, just inhale through your nose. And then take a second short inhale and then exhale fully and slowly through your mouth. That long exhale activates your nervous system. I just did it, I feel relaxed already. Two minutes can change your state, literally. Just try, even five breaths can change your state. Just do five deep breaths, profound and rapid change. You always have that accessible to you. Okay, so let's say you clean up your diet and you start exercising, you even cut alcohol and you go to sleep earlier. But the scale isn't moving.

• 8:56Dr. Mark Hyman?

  I want you to know this is bigger than willpower. It could be your insulin. Yes, your glucose can still look fine and you can still be walking around with very elevated insulin. It's the fat storage hormone. When it stays high, your body gets one message, hold on to that weight. And no amount of discipline can override that signal. And insulin doesn't act alone. When you pair it with higher levels of something called high sensitivity CRP, a marker for inflammation, this stubborn weight is no longer a mystery. It becomes predictable. It's time to stop guessing. Check your health with Function. Function gives you access to over 160 lab tests every year, including advanced lipoprotein testing. It's time to stop guessing. Check your health with Function.

• 9:41Dr. Mark Hyman?

  Go to functionhealth.com/mark. And if you're one of the first 1,000 people this week, use the code MARK2026 for a $50 credit toward your $365 a year membership. That's functionhealth.com/mark and use the code MARK2026 today. Next pro tip is build muscle. Muscle isn't just about looking good or aesthetics. It improves insulin sensitivity and increases mitochondrial density, but also enhances stress resilience. So strength training is one of the most powerful nervous system stabilizers we have because muscle is your metabolic armor. Next, protect your sleep because when your sleep is not good, you're in trouble. Sleep is when your body and your nervous system recalibrates. So how do you fix your sleep?

• 10:25Dr. Mark Hyman?

  Get morning light exposure. Sleep at a consistent bedtime. Not always ideal, but can. Reduce your evening stimulation. So don't do stimulating things right before bed. Avoid blood sugar crashes before bed. Because meaning don't eat a lot of sugar and starch at dinner. If you don't sleep, you can't regulate. So make sure you prioritize sleep. Next, you want to create safety cues. The nervous system responds more to cues of safety than to positive thinking. So what is that? Nature, connection, community, touch, laughter, time offline, which I love. Your biology is always scanning for safety. Just give it those signals. They're available to you.

• 11:07Dr. Mark Hyman?

  All right, what are the myths about nervous system regulation? And when it comes to nervous system function? Is nervous system regulation just meditation? No, it's metabolic, it's relational, it's physiological. If I'm productive and high achieving, I must be regulated. Not necessarily. I'm an example of that. You may be, as you're running on adrenaline, which I did for many years. Can I biohack my way out of stress? Well, not if your lifestyle stays chaotic. If I calm down, I lose my edge. Well, actually, regulation improves focus, performance and clarity. So you do better. So here's the bottom line. A regulated nervous system is not a luxury. It's the foundation of healing.

• 11:47Dr. Mark Hyman?

  If you feel stuck, whether it's weight gain, hormone dysfunction, gut issues, inflammation, just ask yourself, does my body feel safe? Because healing happens in safety. So start small. Balance your breakfast, lift something heavy, breathe for two minutes. Every morning I wake up and I do a breath work practice for five minutes. It's amazing. I love starting my day like that. Go outside, get some fresh air, get some sunlight, prioritize your sleep. You don't heal by fighting with your body. You heal by teaching it that it's safe to repair. And when you do that, everything changes. Now, if you want to go deeper, I want you to keep an eye out for my upcoming episode on my podcast with Dr. Scott Shear.

• 12:29Dr. Mark Hyman?

  We're exploring the emerging theories and the practical tools for regulating nervous system and unlocking the body's healing capacity. Take a listen to this short clip from our conversation. Today, I really want to like have people who are listening to understand, you know, what, what is going on with their, their energy? What is going on with stress? And what, what are the psychological and the physiological? Logical cause of stress. And how do we start kind of navigating this from a therapeutic perspective? Because like, we all want out of this. I, as soon as like, yeah, I'm in this sympathetic spiral of doom, and I want the hell out of this thing. So what is it? Explain it to us. Unpack it for us.

• 13:05Speaker 01

  Well, thanks again for having me, Mark. And, and you know, what I, what I like to just describe here is it's not a diagnosis for people. This is more of a pattern, as you mentioned, it's an age old pattern. But I realized recently that it was really a significant discovery for me to understand that it's a spiral and it's a loop. You have sympathetic activation, which is your fight or flight, your nervous system being activated. You have mitochondrial dysfunction. Mitochondrial dysfunction, mitochondria, as all your listeners know, is a part of our cells that make energy. The combination of sympathetic activation, mitochondrial dysfunction, is a loop. And what happens here is that this loop can either start with mitochondrial dysfunction directly, that's what I call bottom up, or it can start with sympathetic activation from outside stressors. Say it's your job, your relationship,

• 13:50Speaker 01

  you have a snoring partner that is snoring and you can't get to sleep at night, outside stresses, or even like worse things like trauma or things that happen when you were younger that have maintained you in this place where you can't stay safe. Either way, whether it starts with mitochondrial dysfunction directly, or it starts with sympathetic activation externally, or for most people, it's both.

• 14:08Dr. Mark Hyman?

  Yeah.

• 14:08Speaker 01

  And then it's something that just makes you fall off a cliff. It could be.

• 14:12Dr. Mark Hyman?

  Let me pause you for a sec.

• 14:13Speaker 01

  Yeah.

• 14:13Dr. Mark Hyman?

  Just define sympathetic activation.

• 14:15Speaker 01

  Yeah.

• 14:15Dr. Mark Hyman?

  Because people are like, what is that? And define like, a little bit better mitochondria.

• 14:20Speaker 01

  Sure.

• 14:20Dr. Mark Hyman?

  Because these are, these are central to your thesis.

• 14:22Speaker 01

  For sure.

• 14:23Dr. Mark Hyman?

  Of sympathetic. So let's get our terms right. Because I think if you're like.

• 14:26Speaker 01

  Otherwise, I'd be just be talking doctor.

• 14:27Dr. Mark Hyman?

  I'm sympathetic, you know, I'm sympathetic. No, no, it's not that.

• 14:31Speaker 01

  Yeah, good point. So yeah, so I put them sympathetic to those that are insympathetic. The sympathetic nervous system, so sympathetic is your fight or flight.

• 14:39Dr. Mark Hyman?

  Yes.

• 14:39Speaker 01

  Part of your nervous system. So it's your, it's running away from the proverbial saber tooth tiger, as we somehow always refer to.

• 14:46Dr. Mark Hyman?

  I know.

• 14:46Speaker 01

  I don't know why. But you're getting chased by something.

• 14:49Dr. Mark Hyman?

  Yeah.

• 14:49Speaker 01

  But unfortunately, we're getting chased all the time in modern society.

• 14:52Dr. Mark Hyman?

  Yeah.

• 14:52Speaker 01

  Whether it's with our phones that are actively in our faces all the time, and doom scrolling at three o'clock in the morning, going, why is this the way it is? Or it's outside things like your job, your relationship, but we're not. We don't reward people resting or relaxing. So the sympathetic nervous system is part of your autonomic nervous system. You have your sympathetic branch, which is your activation, fight or flight. And you have your parasympathetic, which is your rest, digest, detoxify and heal. But modern society doesn't reward that side, right? It rewards the hustle. I mean, in medical school, my friends and I had shirts that said, sleep is for quitters.

• 15:27Dr. Mark Hyman?

  Yeah.

• 15:27Speaker 01

  Not surprising.

• 15:28Dr. Mark Hyman?

  That's right.

• 15:28Speaker 01

  I grew up in New York.

• 15:29Dr. Mark Hyman?

  Surgeons don't have lunch. That was ours.

• 15:31Speaker 01

  Yeah, there you go. Same kind of thing. Like you just, you hustle, right? You go and you grind, right? That's what we reward. And then unfortunately, that's how society has created this stress externally for us that we have to perform, we have to have more meetings, we have to do more, do more, do more all the time. And so instead of just running away from the saber tooth tiger and then, you know, hanging out the rest of the day because hopefully we lived, maybe we probably didn't, but in some cases we did, right? Then you would have the time to relax because your nervous system would be activated and then it'd be shut off. But that's not how modern society works anymore, as you know. We're constantly stressed, constantly on pressure, constantly on meetings. And that's that sympathetic activation. And most of us kind of think we thrive in that, in that environment. And we can for a little while.

• 16:15Speaker 01

  But the problem is that when you're sympathetic all the time, you're releasing hormones like cortisol, your neurotransmitters like norepinephrine and epinephrine.

• 16:22Dr. Mark Hyman?

  Adrenaline.

• 16:22Speaker 01

  And adrenaline, yes. Noradrenaline, adrenaline that are stimulating the whole system to work harder. Because if you're in that sympathetic nervous system activation all the time, I call it sympathetic overdrive, you're just shoving all those neurotransmitters and hormones out all the time. And that causes deterioration in immune system function, in hormone function, and in your mitochondria itself. So to define mitochondria, which we can do now.

• 16:44Dr. Mark Hyman?

  Yeah.

• 16:45Speaker 01

  The mitochondria are part of the cell that helps make energy, right? When I was in high school, my, my daughter is in ninth grade, she learned, she's got the, the basic cell. She just learned, she's like, dad, check out the basic cell. It's got a nucleus, it's got cytoplasm, it's got Golgi bodies, and it's got this one little cool organelle called the mitochondria. I'm like, huh, this is what I learned when I was probably that age too.

• 17:04Dr. Mark Hyman?

  Yeah.

• 17:04Speaker 01

  You learn that the cell has one mitochondria, but that is far from the case.

• 17:08Dr. Mark Hyman?

  It has like thousands.

• 17:09Speaker 01

  Some cells in our body have thousands of mitochondria per cell. And some cells, actually, there's one human cell that has zero, and that's the red blood cell.

• 17:15Dr. Mark Hyman?

  Yeah, the red blood.

• 17:15Speaker 01

  Right. But most mitochondria per cell are in our reproductive organs. Eggs, oocytes, sperm are the number one and number two.

• 17:23Dr. Mark Hyman?

  They gotta swim, they need a lot of energy to swim.

• 17:25Speaker 01

  Yeah. And the eggs have more though. Women have to, you know, create, make the baby. And so they have more. But then just behind that is your brain, your heart. Your liver, your musculoskeletal tissue. So detox, everybody is hugely energetically intensive.

• 17:38Dr. Mark Hyman?

  Liver, yeah.

• 17:38Speaker 01

  People don't realize that is like if you need it, if you're going to be able to detox, you have to have a huge amount of mitochondrial energy.

• 17:44Dr. Mark Hyman?

  So you remember, you are not powerless in this process. You have far more influence over your biology than you've been told. When you learn to work with your nervous system instead of against it, you take back control of your health and that's where real transformation begins.

• 17:59Dr. Mark Hyman?

  Thanks for joining me for Office Hours. I love diving into these topics with you. Remember, you are the CEO of your own health and every choice you make can move you closer to healing and vitality. I want to keep these episodes as relevant and useful as possible. So tell me, what do you want to explore next? What questions are you wrestling with? What breakthroughs are you chasing? Share your ideas in the comments on social media or through the link in the show notes. I'm listening. Until next time, keep taking charge, keep asking questions and keep showing up for your health.

• 18:37Dr. Mark Hyman?

  If you love this podcast, please share it with someone else you think would also enjoy it. You can find me on all social media channels at Dr. Mark Hyman. Please reach out. I love to hear your comments and questions. Don't forget to rate, review and subscribe to the Dr. Hyman Show wherever you get your podcasts. And don't forget to check out my YouTube channel at Dr. Mark Hyman for video versions of this podcast and more. Thank you so much again for tuning in. We'll see you next time on the Dr. Hyman Show. This podcast is separate from my clinical practice at the Ultra Wellness Center, my work at Cleveland Clinic and Function Health, where I am Chief Medical Officer. This podcast represents my opinions and my guests' opinions. Neither myself nor the podcast endorses the views or statements of my guests. This podcast is for educational purposes only and is not a substitute for professional care by a doctor or other qualified medical professional.

• 19:22Dr. Mark Hyman?

  This podcast is provided with the understanding that it does not constitute medical or other professional advice or services. If you're looking for help in your journey, please seek out a qualified medical practitioner. And if you're looking for a functional medicine practitioner, visit my clinic, the Ultra Wellness Center at ultrawellnesscenter.com and request to become a patient. It's important to have someone in your corner who is a trained, licensed healthcare practitioner and can help you make changes, especially when it comes to your health. This podcast is free as part of my mission to bring practical ways of improving health to the public. So I'd like to express gratitude to sponsors that made today's podcast possible. Thanks so much again for listening.