Essentials: Boost Your Energy & Immune System with Cortisol & Adrenaline

0:00Welcome to Huberman Lab Essentials, where we revisit past episodes for the most potent and actionable science -based tools for mental health, physical health, and performance. I'm Andrew Huberman and I'm a professor of neurobiology and ophthalmology at Stanford School of Medicine. This podcast is separate from my teaching and research roles at Stanford. It is, however, part of my desire and effort to bring zero cost to consumer information about science and science -related tools to the general public. Today, we're going to focus on how particular hormones influence our energy levels and our immune system.

0:35We're going to talk about the hormones cortisol and epinephrine, also called adrenaline. If you're somebody who has challenges with sleep or you're somebody who has challenges getting your energy level up throughout the day and getting your energy level down when you want to sleep, today's episode is also for you. And we're going to talk about the immune system and how to enhance the function of your immune system. I think it's fair to say that most people would like to have a lot of energy during the day, if you work during the day, and they'd like their energy to taper off at night. And I think it's fair to say that most people don't enjoy being sick.

1:11And it turns out that the two hormones that dominate those processes of having enough energy and having a healthy immune system are cortisol and epinephrine. I just want to cover a little bit about what cortisol and epinephrine are, where they are released in the body and brain, because if you can understand that, you will understand better how to control them. First of all, cortisol is a steroid hormone, much like estrogen and testosterone, in that it is derived from cholesterol. So understand that cholesterol is a precursor molecule, meaning it's the substrate from which a lot of things like testosterone and estrogen are made.

1:55Please also understand that cholesterol can be made into estrogen or testosterone or cortisol, and that cortisol is sort of the competitive partner to estrogen and testosterone. What this means is no matter how much cholesterol you're eating or you produce, whether or not it's low or it's high, if you are stressed, more of that cholesterol is going to be devoted toward creating cortisol, which is indeed a stress hormone. However, the word stress shouldn't stress you out because you need cortisol. Cortisol is vital, you don't want your cortisol levels to be too low. It's very important for immune system function, for memory, for not getting depressed.

2:37You just don't want your cortisol levels to be too high, and you don't want them to be elevated even to normal levels at the wrong time of day. Epinephrine or adrenaline has also been demonized a bit. We think of it as this stress hormone, this thing that makes us anxious, fight or flight. The fact of the matter is that epinephrine is your best friend when it comes to your immunity, when it comes to protecting you from infection. And epinephrine, adrenaline, is your best friend when it comes to remembering things and learning and activating neuroplasticity. We're going to talk about that as well.

3:14Once again, it's a question of how much and how long and the specific timing of release of cortisol and epinephrine as opposed to cortisol and adrenaline being good or bad. They're terrific when they're regulated. They are terrible when they're misregulated, and we will give you lots of tools to regulate them better. I'd like to take a quick break and acknowledge one of our sponsors, BetterHelp. BetterHelp offers professional therapy with a licensed therapist carried out entirely online. I've been doing weekly therapy for well over 30 years. Initially, I didn't have a choice. It was a condition of being allowed to stay in school, but pretty soon I realized that therapy is an extremely important component to overall health.

3:53In fact, I consider doing regular therapy just as important as getting regular exercise, including cardiovascular exercise and resistance training, which of course I also do every week. There are essentially three things that great therapy provides. First of all, it provides a good rapport with somebody that you can trust and talk to about all issues that you're concerned about. Second of all, it can provide support in the form of emotional support or directed guidance. And third, expert therapy can provide useful insights. With BetterHelp, they make it very easy to find an expert therapist with whom you resonate with and can provide those benefits that come through effective therapy.

4:27Also, because BetterHelp allows therapy to be done entirely online, it's very time efficient. If you'd like to try BetterHelp, go to BetterHelp .com slash Huberman. For this month only, March 2025, BetterHelp is giving you the biggest discount offered on this show, with 90 % off your first week of therapy. Again, that's BetterHelp .com slash Huberman to get 90 % off your first week. Today's episode is also brought to us by Element. Element is an electrolyte drink that has everything you need, but nothing you don't. That means the electrolytes, sodium, magnesium, and potassium, all in the correct ratios, but no sugar.

5:03Proper hydration is critical for optimal brain and body function. Even a slight degree of dehydration can diminish cognitive and physical performance. It's also important that you get adequate electrolytes. The electrolytes, sodium, magnesium, and potassium, are vital for the functioning of all the cells in your body, especially your neurons or your nerves. Drinking Element dissolved in water makes it extremely easy to ensure that you're getting adequate hydration and adequate electrolytes. To make sure that I'm getting proper amounts of hydration and electrolytes, I dissolve one packet of element in about 16 to 32 ounces of water when I wake up in the morning, and I drink that basically first thing in the morning.

5:38I also drink Element dissolved in water, drink any kind of physical exercise that I'm doing. They have a bunch of different great -tasting flavors of element. They have watermelon, citrus, etc. Frankly, I love them all. If you'd like to try Element, you can go to drinkelement .com slash Huberman Lab to claim a free Element Sample Pack with the purchase of any Element Drink Mix. Again, that's drinkelement .com slash Huberman Lab to claim a free Sample Pack. Court is all biology 101 in less than two minutes. Your brain makes what we call releasing hormones, and in this case, there's corticotropin releasing hormones.

6:13C -R -H is made by neurons in your brain. It causes the pituitary, this gland that sits about an inch in front of the roof of your mouth and the base of your brain, to release A -C -T -H. A -C -T -H then goes and causes your adrenals which sit above your kidneys and your lower back to release cortisol. A so -called stress hormone, but I would like you to think about, Court is all not as a stress hormone, but as a hormone of energy. It produces a situation in the brain and body whereby you want to move and whereby you don't want to rest and whereby you don't want to eat, at least at first. Epinephrine or adrenaline 101 in less than two minutes.

7:03When you sense a stressor with your mind or your body senses a stressor, excuse me, from a wound or something of that sort, a signal is sent to neurons that are in the middle of your body, they call the sympathetic chain ganglia, the name doesn't necessarily matter. They release an epinephrine very quickly, it's almost like a sprinkler system that just hoses your body with epinephrine. That will increase heart rate, will increase breathing rate, it will also increase the size of vessels and arteries that are giving blood flow to your vital organs. You also release adrenaline from your adrenals, again, sitting riding a top of your kidneys.

7:43You release it from an area of your brain called locus serulius and that creates alertness in your brain. We have cortisol and we have epinephrine and their net effect is to increase energy. The first tool is to make sure that your highest levels of cortisol are first thing in the morning when you wake up. One way or another, every 24 hours, you will get an increase in cortisol. It's to stimulate movement from being asleep, presumably horizontal, to getting up and starting to move about your day. The best way to stimulate that increasing cortisol at the appropriate time is that very soon after waking within 30 minutes or so after waking, get outside, view some sunlight.

8:27Even if it's overcast, get outside, view some sunlight, no sunglasses, do that. Because in the early part of the day, you have the opportunity to time that cortisol release to the early part of the day. It will improve your focus, it will improve your energy levels, and it will improve your learning throughout the day. So here's how it works. On a sunny day, so no cloud cover, provided that the sun is not yet overhead, it's somewhere low in the sky, could have just crossed the horizon or if you wake up a little bit later, it could be somewhat low in the sky. Basically, the intensity of light, the brightness, is somewhere around 100 ,000 lux.

9:06Lux is just a measurement of brightness. On a cloudy day, it's about 10 ,000 lux. So 10 fold reduction. But bright artificial light, very bright artificial light, is somewhere around a thousand lux. And ordinary room light is somewhere around 100 to 200 lux. So even if you have a very bright bulb sitting right next to you, that's not going to do the job. Your phone will not do the job, not early in the day. To get the cortisol released at the appropriate time, you need to get outside. So let's just set a couple general parameters. If it's bright outside and no cloud cover, get outside for 10 minutes.

9:47If it's a cloudy day, dense overcast, you're probably going to need about 30 minutes. If it's light cloud, broken cloud cover, it's probably going to be somewhere between 10 and 20 minutes. This is why it's vital to get this light on a regular basis, to get that cortisol released early in the day. That sets you up for optimal levels of energy. Now throughout the day, you're going to experience different things. Most of you are not spending your entire day trying to optimize your health. You know, some of you might be, but most of you have jobs and you have families and you have commitments. Life enters the picture and provides you stressors.

10:22Those will cause increases in cortisol and epinephrine. The key is these blips in cortisol and epinephrine need to be brief. You can't have them so often or lasting so long that you are in a state of chronic cortisol elevation or chronic epinephrine elevation. This system of stress was designed to increase your alertness and mobilize you towards things, get you frustrated and provide the opportunity to change behavior. The reason it works is that cortisol, when it's released into the bloodstream, it actually can bind to receptors in the brain. It can bind receptors in the amygdala, fear centers and threat detection centers, but also areas of the brain that are involved in learning and memory and neuroplasticity.

11:09This is why I say that neuroplasticity, the brain's ability to change itself in response to experience, is first stimulated by attention and focus and often a low level state of agitation. Understand that and you won't be quite so troubled about the little stress increases that you experienced throughout the day. There are ways to leverage stress, epinephrine and cortisol in ways that serve you and to do it in a deliberate way. There are also ways to do that that increase your level of stress threshold, meaning they make it less likely that epinephrine and cortisol will be released. I want to talk about the science of those practices because I get asked about these practices a lot, things like Wim Hof breathing, which is also called tummo breathing, things like ice baths, things like high intensity interval training.

12:00All of those things have utility. The question is how you use them and how often you use them. Those tools, just like stress from a life event, can either enhance your immunity or deplete it. That's right, those same practices of ice baths, tummo breathing, high intensity interval training or training of any kind can deplete your immune system or it can improve them. Excuse me, they can improve it, meaning they can improve your immune system. The key is how often you use them and when. I want to review that now in light of the scientific literature because in doing that, you can build practices into your daily or maybe every other day routine that can really help buffer you against unhealthy levels of cortisol and epinephrine, meaning cortisol increases that are much too great or that last much too long.

12:52Epinephrine increases that are much too great or that last much too long. Let's say somebody tells you something very troubling or you look at your phone and you see a text message that's really upsetting to you. That will cause an immediate increase in epinephrine adrenaline in your brain and body and chances are it's going to increase your levels of cortisol as well. Let's say you get into an ice bath or a cold shower. That will cause an equivalent increase in epinephrine and cortisol. Let's say you go out for high intensity interval training, you decide you're going to run some sprints, you do some repeats, or you're going to do some weightlifting in the gym or you decide that you want to do some hot yoga, you're going to increase your epinephrine and cortisol levels.

13:36And guess what, they increase your levels of energy and alertness. So if you're somebody who struggles with energy and alertness, it can be beneficial provided you get clearance from your doctor to have some sort of protocol built into your day where you deliberately increase your levels of epinephrine and your levels of cortisol. So it's really important to understand that the body doesn't distinguish between a troubling text message, ice, tumble breathing, or high intensity interval training or any other kind of exercise. It's all stress. Cognitively reframing that and telling yourself, I like this, I enjoy it, is not going to change the way that that molecule impacts your body and brain.

14:17I sort of chuckle because people would love to tell you that all you have to do is say, oh, this is good for me. No, what it does to tell yourself that it's good for you or that you enjoy it, is that it liberates other molecules like dopamine and serotonin that help buffer the epinephrine response. Now, the way that it does that, I've talked about previous episode, but I'll just mention that dopamine is the precursor to epinephrine. Epinephrine is made from dopamine. And that's why if you tell yourself you're enjoying something and because dopamine is so subjective that you can in some ways, as long as you're not completely lying to yourself, you can get more epinephrine.

14:57You get more mileage or more ability to push through something and you can sort of reframe it, but it's not really cognitive reframing. The cognitive part is the trigger, but it's a chemical substance that's actually occurring there. It's dopamine giving you more epinephrine, a bigger amplitude epinephrine release, and it gives you some sense of control. So here's a protocol that anyone can use if you want to increase levels of energy, if you suffer from low energy during the daytime or whenever it is that you'd like to be alert. Pick a practice that you can do fairly consistently, maybe every day, but maybe every third day or every fourth day, maybe it's an ice bath or a cold bath, maybe it's a cold shower, maybe it's the cyclic inhale, exhale breathing protocol, I describe.

15:46If that wasn't clear and people always ask for a demo, I'm not going to do the whole thing right now, but I'm willing to do a few rounds of this or a few cycles, I should say so it's inhale. I would do that more deeply, more like you do that 25 30 times repeatedly, you will start to feel warm people in the yoga community say you're generating heat, you're not generating heat, releasing adrenaline, inhale, exhale, inhale, exhale 25 or 30 times, you will feel agitated and stressed. That's because you're releasing adrenaline in your body and that's because you're releasing nor appinepheren in your brain and you'll be more alert.

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17:33How do we actually benefit from them? Now of course, the cold itself can have some health promoting effects. It can increase brown fat thermogenesis and metabolism, high intensity interval training or other forms of exercise. Of course has cardiovascular effects that can be good for us as does weight training, etc. But what we're talking about here are ways to increase energy and to teach our brain and body to teach ourselves how to regulate the stress response. So in addition to the benefits of the actual practices, what we're talking about is building a system so that when you experience increases in epinephrine and cortisol from life events, you're able to better buffer those.

18:16And we are also talking about ways that you can increase energy overall, because that's what today's episode is all about energy and immune system. There's a biological mechanism that's very important if you want to do those things. Increase energy and your immune system on demand. Learn to buffer stress on demand in real time. And it means taking these protocols, these practices, whether or not it's cold water or ice bath or exercise or any of those, and making one small but very powerful adjustment in how you perform them. But in order to make that adjustment, I can't just tell you the adjustment.

18:54I have to tell you the mechanism so that you know if you're doing it correctly or not. This is really a case where if you can understand a little bit of mechanism, you will be far better off than just adopting protocols. Cortisol, as I mentioned, is released from the adrenals. It can have action both in the body and in the brain. Cortisol can cross the blood brain barrier. Epinephrine cannot. That's one of the reasons why it's released both from the adrenals in your body and released from this brainstem area of the locustaruleus in your brain. That's a powerful thing because what it means is that the body can enter states of readiness and alertness while the mind remains calm.

19:39So I'm presuming at this point that you're getting your morning light to time your cortisol increase. I'm presuming that you want more energy or that you want to increase your immune system. It's function and it's ability to combat infections of various kinds. Now, the simplest way to describe how to do that would be in the context of cold water or a breathing protocol. Let's presume cold water. So let's say you decide you're going to take a cold shower. You get into the cold shower and if it's cold enough, that will be stressful. You will experience an increase in epinephrine. It will increase your alertness.

20:14Now, you're using this as a practice as a tool to build. You could call it resilience, but the ability to stay calm in the mind while being stressed in the body, epinephrine is in the body. And you do that by subjectively trying to calm yourself. Now, you can do that by telling yourself it's good for you by emphasizing your exhales. Anything that you can do to try and stay calm, despite the fact that you are in a heightened state of alertness. You do this with exercise, you do this with music, pretty much anything that will give you a really heightened state of alertness, offers you the opportunity to try and stay calm in the mind.

20:49What you're trying to do at a mechanistic level is to have adrenaline released from the adrenals, but not have adrenaline epinephrine released from the brainstem to the same degree. So you're not just trying to buffer this. You're not trying to say, oh, this is good for me. This is good for me. I'm going to grind this out. You're not trying to grind it out. You're trying to move through this calmly while maintaining alertness in the immediate period following that practice. Your system, your entire brain and body are different. Your body is actually primed to resist infection when you have high levels of epinephrine in it for short periods of time.

21:28So the scientific study that explored how increasing adrenaline in the body can improve immune resistance is grounded in a well -known phenomenon that increases in stress actually protect you against infection in the short term. So I want to look at the classic data first, describe what was done, and then I want to talk about the more recent study, which is immediately actionable. There are classic set of studies that are really based mainly on the work of somebody named Bruce McEwan, who is at the Rockefeller University in New York. I'm not going to go through all the details of the study, but essentially what they were doing was exposing subjects to some sort of infection, either bacterial or viral infection, and inducing stress.

22:13Sounds like a double whammy, right? You'd think that maybe getting a little electric foot shock or cold water exposure, or something to increase your levels of stress in an adrenaline would just make the effects of the infection worse, but no, quite the opposite. Brief bouts of stress, which now you should be thinking about in terms of cortisol and epinephrine release, were actually able to increase immune system function. The duration here is really important, because if stress stayed too high for too long, then yes, indeed, stress can hinder the immune response. But for a period of about one to four days, it actually can protect you by way of increasing the immune response.

22:56There's a human study that I definitely want to point out to you because it was published more recently than the McEwan work. The title of the paper is voluntary activation of the sympathetic nervous system. That's the system that causes fighter flight and AK stress. This is Cox K -O -X at all P -N -A -S, Prosting's the National Academy of Sciences 2014, and they incorporate the ever famous Wim Hof breathing. Here's what they did. They injected people with E -Coli, and they had groups that either did the sorts of breathing I've been describing that increased adrenaline release. Although I should say I don't think you need that breathing to get adrenaline release.

23:39You could do it with cold exposure. You could do it with other things, high intensity interval training as well. What they found was that the response to the E -Coli was quite different in the people that had a protocol, in this case breathing, to increase adrenaline. This is a remarkable study because what they found was that the fever, the vomiting, all the negative effects of E -Coli, many of them, in some cases, all of them were greatly attenuated by way of engaging the adrenaline system. The point is you can control your immune system by finding a way that you can increase adrenaline. This runs counter to what we always hear, which is don't get too stressed or you will get sick.

24:26Learn to control adrenaline, turn it on and turn it off. Learn to control cortisol, turn it on with light in the morning, try and turn it off, and then when it spikes because of life events, learn to turn it off. Learn to turn on and off adrenaline, aka epinephrine, and learn to turn on and off cortisol, afford to the ability to turn on energy and focus in your immune system. That's the most important point from today's podcast and understanding that it doesn't matter what protocol you use. Maybe it's a cup of coffee and running up a hill five or six times. That will improve your immune system function if you get adrenaline in your system.

25:06You can use an ice bath, you can use a cold bath, it really doesn't matter. I'd like to take a quick break and acknowledge one of our sponsors, Function. Last year I became a function member after searching for the most comprehensive approach to lab testing. Function provides over 100 advanced lab tests that give you a key snapshot of your entire bodily health. This snapshot offers you with insights on your heart health, hormone health, immune functioning, nutrient levels, and much more. They've also recently added tests for toxins such as BPA exposure from harmful plastics and tests for PFASs or forever chemicals.

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