Unlocking Longevity: The Transformative Benefits of Infrared Saunas
Infrared heat uncouples mitochondria, doubles cardiac output, and builds the cellular foundation that protects against the diseases of aging — all without a single step taken.
Video·The Dr. Gundry Podcast·10 min read·June 2026
How regular infrared sauna sessions uncouple your mitochondria, replicate cardiovascular exercise, and support protection against the diseases of aging.
The Mitochondria Mechanism
The case for infrared sauna begins not with sensation but with cellular biology. At its foundation is a principle called heat hormesis: the deliberate use of controlled thermal stress to prompt the body to adapt, repair, and emerge stronger. The term hormesis draws from Nietzsche's observation that what does not kill us makes us stronger — a formulation that turns out to be strikingly accurate at the level of the cell. Heat is a stressor; the body reads it, responds, and the adaptation that follows is measurable and lasting.
one of the best things you can do for your health is uncouple your mitochondria
Mitochondria are the engines of cellular energy, converting nutrients into the fuel that powers every function the body performs — from physical recovery to mental clarity to sustained endurance. Under sustained sauna heat, they come under genuine metabolic pressure. The weak or non-functioning mitochondria do not survive the challenge. The healthy ones respond by uncoupling — dispersing heat while simultaneously driving deeper cellular adaptation — and emerge from each session more efficient and more resilient. What the body loses in the weakest elements, it more than recovers in the strengthened remainder.
Near-infrared light amplifies this process through an additional pathway. Research published in the Journal of Photochemistry and Photobiology indicates that red and near-infrared light therapy may increase the actual count of mitochondria within cells — not merely optimize the function of those already present. The mechanisms proposed include mitochondrial uncoupling itself, among others. The practical implication is significant: more mitochondria operating more efficiently translates into greater sustained energy, improved capacity for recovery, and a cellular foundation better equipped to resist the gradual metabolic decline that accumulates with age.
Human clinical studies confirm the scale of the thermal effect an infrared sauna produces. Sessions have been documented to raise core body temperature by up to three degrees Celsius — a magnitude of internal thermal shift that activates the body's full adaptive response. This is not incidental warmth or ambient comfort; it is a deliberate physiological signal. The body registers that signal with precision and responds with the same cellular mechanisms it deploys to survive and adapt to real physical stress.
Hormesis is not about extremity. It is about calibration — applying the right stressor in the right amount to prompt meaningful adaptation without causing harm. The infrared sauna achieves this calibration reliably: enough heat to challenge mitochondria, drive uncoupling, and elevate cellular repair processes; contained enough to be sustained session after session. The result, practiced consistently over time, is a cellular environment that produces more energy, recovers more efficiently, and maintains the biological conditions for a long and vital life.
Well as I often talk about, one of the best things you can do for your health is uncouple your mitochondria. There are many ways to do this like eating pistachios, swallowing polyphenols, taking MCT oil and ice baths to name a few. But one of my personal favorite ways to uncouple mitochondria that is support our longevity is regular sauna use and this has become even easier. Thanks to my new infrared sauna saunas are widely available and may even be free to use at your local health club. So they're a great option for temperature induced torme. And if you're not a fan of the sweaty part or sitting around half naked with a bunch of strangers, you can get a similar effect and even more benefits for your mitochondria from an infrared sauna.
The brand I decided to go to for my personal use is sun lighten. They have been committed to helping others with their products for nearly years really long before the sauna craze was even heard of. Now, why do this? Well, first of all these saunas have great benefits. Number one right up on the top of the list is uncoupling mitochondria, extreme temperatures you might experience in a sauna, can uncouple your mitochondria. First of all, the heat hormesis is a short term stress that also has healing benefits. The word hormesis first got coined from Nietzsche's famous line that which doesn't kill me, makes me stronger. So, hormesis is using a stressor to get a benefit from that stressor. And heat actually stresses your mitochondria,
the weak ones or the nonfunctioning ones die off while the others uncouple and divine. And there's excellent studies to show that this happens. Now, sunlighten saunas are proven to raise body temperature by up to three degrees in human clinical studies. But it's the near infrared exposure, that's really exciting a paper in the Journal of Phyto Chemistry and phyto biology explained that red light therapy might increase the number of mitochondria by a multiple mechanism including mitochondrial and coupling. Now, exercise will uncouple mitochondria. Physical exercise seems to globally stimulate mitochondrial uncoupling leading to a remodeling of skeletal muscle cell physiology. But infrared sauna sessions raise your heart rate and increase circulation.
And this replicates a cardiovascular workout. We turn passive cardio. In fact, blood flow during infrared sauna use may raise from a normal rate of about to liters or quarts per minute to up to quarts per minute, liters per minute, basically a doubling of your cardiac output. And this is human studies. Now an additional benefit that many people have used sauna for generations is that it can loosen up your muscles. Now, red light and near infrared light can help build muscles and decrease inflammation and oxidative stress. The heat of infrared increases circulation of blood flow. Now, obviously, red blood cells carry oxygen and nutrients to the site of a strain or inflammation, which actually helps create new blood vessels and tissues at the site.
So the more red blood cells that get delivered to your muscles, the quicker they rebuild. And since white blood cells are the cleanup agents, the more white blood cells you develop, deliver to your muscles from increasing blood flow, the quicker the inflammation gets cleaned up. Now, there's more to it than just that a study conducted at Auburn University of Montgomery showed a sunlight and impulse sauna can increase your flexibility by up to three times benefits. In the study showed an increased range of motion including joint mobility, less friction in the joints and diminished stiffness and joint relaxation. Again, a published study in humans, with this increase in flexibility, you can expect a decrease risk of injury because the less stress that's placed on the muscles if moving properly.
Now, all of this can have energy boosting effects including helping to alleviate fatigue symptoms, mostly because of its ability to support circulation and dilated blood vessels. In fact, in one study of patients suffering from chronic fatigue syndrome, symptoms were dramatically improved after 15 to 25 sessions of thermal therapy. Why? Because among other things, red and near infrared therapy support mitochondrial function and the efficient production of ATP through cellular respiration. Another published study. Now, the nice thing that I like about infrared saunas, they operate at a much lower temperature than traditional saunas. And with the sunlighten sauna, you don't have to wait for the sauna to heat up because
the infrared energy makes you heat up rather than the air around you heat up. This temperature difference allows you to leave the sauna feeling refreshed rather than drained. In other words, you get to enjoy the experience rather than endure the experience. And if you've ever endured saunas, particularly after skiing or at the gym, you'll know that one of the feelings you get is certainly not one of thoroughly enjoying the experience but kind of suffering through the experience to get the benefit. Later in this case, you actually get to enjoy the experience and oh, by the way, we can pipe in music in our sauna to really enhance the experience. Now, infrared saunas can give cardiovascular systems the same boost as exercising.
And that's because your cardiac output goes up, your blood vessels dilate. And that's a great thing. Now, when exposed to the stresses of extreme heat, cells engage in coordinated adaptive measures that stimulate them to clean up, repair, restore themselves. And that's what the hormesis response is. One of the benefits of frequent sauna use that's been documented in sauna using countries is that it appears to be protective against cardiovascular and neurodegenerative disease. That's pretty good. In fact, repeated. So use has shown to preserve muscle mass and countering sarcopenia in humans. Now to do all that, you can spend time in a sauna or a steam room, you can get a near infrared or red light sauna for your home
use like sunlighten, you can take a hot yoga class or quite frankly, come and visit me in Palm Springs in the summer. I guarantee you you will get a hot experience, but there's an easy way that I used to use all the time. That is take a nice hot bath to enjoy sampling these benefits and take it before you go to bed. Recent studies show that a hot bath relieves mild depression better than antidepressants and a hot bath before bedtime will make you drop your temperature, which will induce a better and deeper sleep. Now get into the bathtub with the bathtub warm and then once you're acclimated, let water out and add hotter and hotter water, you'll achieve the same hormetic effects as long as you're sweating in the bathtub.
Now you hear about cold showers, but it goes both ways. Exposing your body to cold and hot temperatures can support a long vital life. And get yourself a sauna. I love my sunlighten sauna. But if you don't have one and want some benefits, fill that bathtub full of hot water before you go to bed and watch the benefits. And you may notice that those benefits will translate into you looking into a sauna for long-term use. like I did. More amazing episodes just like this one. Watch now! If you really want to spend your money on a calcium supplement, buy some sardines, buy some anchovies, that's the way to get your calcium.
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Why Infrared Feels Different
Traditional saunas heat the air, and the experience arrives as a wall — dense, immediate, requiring acclimatization before any meaningful effect begins. Infrared saunas operate on a different principle. The energy penetrates tissue directly, warming the body from within rather than conditioning the surrounding environment. There is no lag between entering the session and beginning to experience its effect; the infrared begins working the moment contact is established.
This direct tissue-warming mechanism also means infrared saunas function at a significantly lower ambient temperature than traditional models. The heat you feel comes from within, not from superheated air pressing against you. The environment inside is composed and breathable rather than punishing. Sessions end not with depletion — the wrung-out, sodden feeling that traditional sauna often produces — but with clarity and ease. There is a real and consequential difference between a protocol you endure and one you choose to return to.
That distinction shapes everything. Consistency determines long-term outcomes in any wellness ritual more decisively than any single session. A practice that feels genuinely restorative is one you will repeat across weeks and months; a practice that feels like suffering is one you will negotiate away when life becomes full. The lower ambient temperature, the option of a private unit, and the absence of any communal dynamic — locker rooms, shared benches, social calculation — remove the friction that causes other modalities to lapse. Comfort, here, is a feature of the protocol's durability.
you get to enjoy the experience rather than endure the experience
The cardiovascular effect of an infrared session is specific and documented. As core temperature rises, heart rate increases and blood vessels dilate — the same circulatory cascade that moderate exercise initiates. Blood flow may rise from a resting rate of roughly five liters per minute to as much as ten liters per minute during a session: a near-doubling of cardiac output, observed in human clinical studies. This is the physiology behind the passive cardio framing: the heart is working, the vessels are adapting, and the mitochondrial signals firing deliver the same energy and resilience gains as movement — without a single step taken.
Physical training uncouples mitochondria. It remodels skeletal muscle cell physiology at a cellular level — and that uncoupling is among the primary reasons exercise builds resilience, energy, and long-term health. Infrared sauna sessions drive the same process through a different path: raising heart rate, expanding circulation, and stimulating the mitochondrial adaptation that follows from sustained cardiovascular output. The accessible experience — comfortable temperature, private setting, no preparation required — is not a compromise. It is the design of a protocol built for sustained, consistent use.
Circulation, Muscle Recovery, and Flexibility
Heat drives blood to move. As core temperature rises during an infrared session, blood vessels dilate and circulation accelerates throughout the body — a response the physiology initiates to manage thermal load and distribute resources. The practical outcome is direct: oxygen and nutrients arrive faster at strained or inflamed tissue, and the biochemical conditions for repair improve immediately. Circulation is not a side effect of the sauna experience; it is one of its primary delivery mechanisms.
Red blood cells carry the oxygen and building materials that allow damaged muscle fibers to rebuild. The more efficiently they reach a site of strain or inflammation, the faster new tissue forms and recovery completes. White blood cells operate as the body's cleanup agents, clearing the inflammatory byproducts that produce soreness, stiffness, and restricted movement. Infrared-driven circulation delivers more of both in greater volume — accelerating the full repair cycle and returning the body to functional capacity sooner than rest alone would achieve.
A study conducted at Auburn University of Montgomery measured the flexibility effects of infrared sauna use directly. The findings showed that a session can increase flexibility by up to three times — a result produced through specific, documented mechanisms: improved joint mobility, reduced friction within the joint space, diminished stiffness, and a measurable relaxation of the surrounding musculature. These are not abstract markers; they represent a body moving closer to its full mechanical range, with less resistance and greater ease.
Greater range of motion reduces the mechanical stress placed on muscles and connective tissue during movement. When a joint moves through its full arc freely, surrounding tissue does not compensate or absorb forces it was not designed to handle. The cascade from restored flexibility to reduced injury risk is logical and practical — grounded in a published human study, not extrapolation. The outcome for consistent infrared users is a body that trains more efficiently, recovers more completely, and remains structurally resilient over time.
Recovery is not the absence of activity — it is a resource-intensive biological process. Infrared sessions supply what recovery requires: expanded circulation, elevated temperature, and the physiological signal to prioritize repair. Practiced regularly, this builds a rhythm of restoration that compounds across weeks and months, allowing effort to be sustained and increased without the chronic inflammation and stiffness that erode performance when recovery is incomplete. The body that recovers well is the body that can train well — and that continues to do so over years.
Flexibility, in this context, is not a narrow athletic metric. It is a measure of the body's ongoing capacity to move freely and without compensation — a quality that matters in the gym, in daily movement, and in the long arc of physical health across decades. Infrared sauna use supports that capacity at its source, through circulation and cellular recovery that respond to consistent, deliberate application. The improvement accumulates; so do the returns.
Longevity, Energy, and Where to Begin
For those navigating chronic fatigue, the clinical evidence is quietly significant. In a study of patients with chronic fatigue syndrome, symptoms improved dramatically after 15 to 25 sessions of thermal therapy. The connection runs directly through mitochondrial function: red and near-infrared light support efficient ATP production via cellular respiration — the process by which cells convert nutrients into usable energy. When that process is optimized, energy is not manufactured artificially or masked by stimulation; it is restored at its source, returning stamina that fatigue had eroded.
The long-view evidence from populations where sauna use is embedded in daily life points toward outcomes that reach well beyond comfort and recovery. Regular sauna practice appears protective against both cardiovascular and neurodegenerative disease — some of the most consequential conditions associated with the aging process. These findings emerge not from isolated trials but from research on habitual heat exposure accumulated over time. Sauna, practiced consistently, is not simply a recovery tool; it becomes part of the physiological architecture that supports a long, vital life.
Infrared sauna use also preserves muscle. Sarcopenia — the gradual loss of skeletal muscle mass that accelerates through midlife and beyond — contributes to reduced mobility, metabolic decline, and diminished physical independence. Repeated sauna sessions have been documented in human studies to counter this process, sustaining the muscle tissue that underlies both physical performance and metabolic resilience. To preserve muscle is to preserve capacity: the capacity to move well, recover fully, and maintain genuine vitality through the later decades of life.
An infrared sauna at home is one path into this practice — and for many, the natural destination. But the entry point is simpler. A hot bath taken before sleep, beginning at a warm temperature and progressively adding hotter water as the body acclimatizes — the heat-then-drain method — produces genuine hormetic benefit, triggering the cellular repair and resilience gains of a full session. Core temperature rises, the body perspires, and the adaptive response is initiated. Research additionally indicates that the body temperature drop following a hot bath deepens sleep quality — compounding the protocol's value into recovery that extends through the night.
The contrast of heat and cold extends this practice further. Alternating between hot and cold exposure challenges the body across a broader adaptive range, conditioning the vascular system, reinforcing the nervous system's stress-response pathways, and building the kind of resilience that accumulates over time. The entry here is equally accessible: warm bath, cold shower, and the attention to how the body responds. That attention — deliberate, consistent, patient — is the foundation of a sauna ritual. The equipment may evolve; the intention does not.
Begin where you are. The ritual is defined by consistency and intention, not by the sophistication of the setup. Each session — infrared sauna, warm bath, cold contrast — is a deliberate investment in cellular health, cardiovascular resilience, and the kind of sustained vitality that is built quietly, over time, through practice.
Exposing your body to cold and hot temperatures can support a long vital life
