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How to Use Cold & Heat Exposure to Improve Your Health | Dr. Susanna Søberg — Whalespan

Content›Video›How to Use Cold & Heat Expos…

How to Use Cold & Heat Exposure to Improve Your Health | Dr. Susanna Søberg

Andrew Huberman2h 31m · 2023-05-15

Claims Made

241

Claims Supported

187

Support Rate

78%

Support rate

187 of 241 claims supported

187 supported54 partial / not

Claims from this content

168

✓Well SupportedFinnish men using sauna 4-7 times per week have 40-50% lower cardiovascular disease incidence and 40-50% lower all-cause mortality compared to those using it once a week.✓Well SupportedInside Tracker's platform provides actionable protocols to adjust blood markers into ideal ranges for health.✓Well SupportedRegular blood work is essential for monitoring factors impacting immediate and long-term health.✓Well SupportedDeliberate cold exposure can increase the release of catecholamines such as dopamine, epinephrine, and norepinephrine, leading to improved mood for many hours afterward.Well Supported

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Bookmarking — the dossier-vs-overview split is the right call. Most of the time I want overview; sometimes I want receipts.

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Probiotics in Athletic Greens are vital for microbiotic health, which communicates with the brain and immune system to impact immediate and long-term health.

✓Well SupportedAg One (formerly Athletic Greens) is a vitamin, mineral, and probiotic drink that provides foundational nutritional needs.

✓Well SupportedDeliberate cold exposure should feel uncomfortable and trigger a 'cold shock' response.

✓Well SupportedMost people should aim for one gram of quality protein per pound of body weight daily to optimize muscle protein synthesis, reduce appetite, and support metabolic health.

✓Well SupportedThesis designs custom nootropics to achieve specific brain-body states.

✓Well SupportedCovering one's head with a towel in a hot sauna can increase comfort by insulating the brain and prevent nasal and oral burning from hot air.

✓Well SupportedCold and heat exposure have shown effects on hormone health, metabolism, and neurotransmitters like dopamine and epinephrine.

✓Well SupportedMaui Nei venison bone broth provides 25 grams of protein per 100 calories.

✓Well SupportedRepeated deliberate cold exposure leads to increased brown fat activation and mitochondrial density in brown fat cells.

✓Well SupportedDirecting cold showers to the head, back of the neck, and upper back can trigger brown fat adaptation and increase mitochondria in those areas.

✓Well SupportedEngaging in activities that increase norepinephrine, such as exercise and cold showers, can enhance mood.

✓Well SupportedA minimum of 11 minutes of cold exposure per week, divided into 2-4 sessions, is recommended, and the timing does not matter.

✓Well SupportedThe diving reflex, activated by submerging the body in cold water, is a survival system that preserves oxygen and prevents rapid hypothermia.

✓Well SupportedDeliberate cold exposure, particularly up to the neck in water, can be used to achieve important endpoints related to mental health, physical health, and performance.

✓Well SupportedDeliberate cold exposure timing should consider baseline body temperature circadian rhythm to optimize states or avoid interfering with sleep.

◐Partially SupportedShorter durations at colder temperatures are preferred by some over longer durations at warmer temperatures for cold exposure.

✓Well SupportedExposing oneself to various temperatures activates brown fat because it is involved in maintaining homeostatic temperature balance.

✓Well SupportedEmbracing environmental micro-stresses like heat, cold, exercise, and short-term oxygen deprivation helps the body adapt and become more resilient.

✓Well SupportedCold-induced brown fat activation improves glucose and insulin sensitivity, increases fat utilization, and protects against diet-induced obesity.

✓Well SupportedDeliberate cold exposure is effective as long as it is uncomfortable but safe, with water submersion to the neck, limbs, feet, and hands being a common method in studies.

✓Well SupportedAchieving 11 minutes per week of deliberate cold exposure stimulates increases in resilience and core metabolism.

✓Well SupportedDopamine, epinephrine, and norepinephrine are catecholamines that work together to create motivation and heighten focus.

✓Well SupportedCold showers are likely effective for health benefits, similar to other cold exposure methods.

✓Well SupportedAdapting to a cold environment by wearing minimal clothing for a few days can lead to cold adaptation.

✓Well SupportedLow-dose, short-duration cold exposure acts as a hormetic stressor, triggering adaptations that protect the body against future, larger stressors.

✓Well SupportedApproximately 90 minutes of sauna use per week, with sessions of 10-15 minutes, aligns with the concept of hormetic stress for cellular repair via heat shock proteins.

✓Well SupportedDeliberate cold exposure, such as 3 minutes at 49°F, can enhance focus and mood before public speaking or when feeling anxious.

✓Well SupportedDeliberate cold exposure, done safely, can induce long-term health improvements by triggering adaptations similar to exercise.

✓Well SupportedCold water exposure is a potent stimulus for shifting the brain and body's environment, leading to improved well-being for a substantial period afterward.

✓Well SupportedEnding deliberate cold exposure with cold and allowing natural rewarming, rather than immediately transitioning to heat, is recommended for increasing metabolism.

✓Well SupportedA target of 11 minutes of deliberate cold exposure per week, in 2-4 sessions of 2-3 minutes each, can increase metabolism and consistency.

✓Well SupportedIndividuals lacking brown adipose tissue (BAT) may shiver more easily and have poorer temperature regulation during cold exposure.

✓Well SupportedHormesis involves a small amount of cellular damage from stimuli like exercise or cold plunges, which makes the body stronger upon repair.

✓Well SupportedThe primary benefit of cold exposure is the feeling of well-being after exiting the cold.

✓Well SupportedActionable protocols for deliberate heat and cold exposure can be established outside the laboratory to improve metabolism and human health.

✓Well SupportedDeliberate cold exposure can increase immune system markers when performed repeatedly over time.

◐Partially SupportedContinuous activation of brown fat due to high noradrenaline increases blood pressure, causes weight loss, and activates the sympathetic nervous system.

◐Partially SupportedNon-exercise activity thermogenesis (NEAT), characterized by fidgeting and bouncing, can burn 800-2000 calories per day.

✓Well SupportedExperiencing discomfort, such as shivering from cold exposure or the physiological stress of exercise, is crucial for adaptation and health improvement.

◐Partially SupportedKeeping hands above the water during cold water immersion allows for longer exposure duration and pain management.

✓Well SupportedExposing oneself to various temperatures throughout the day is recommended.

◐Partially SupportedCold exposure on the face, such as sleeping in a cool room, can activate brown fat due to high density of cold receptors.

◐Partially SupportedA proof-of-concept study investigated cold water immersion mechanisms using PET scans of brown fat.

✓Well SupportedWinter swimmers shiver less vigorously than control groups, indicating differences in muscle activation.

◐Partially SupportedThe sympathetic nervous system is responsible for accelerations in heart rate, alertness, and the stress response.

◐Partially SupportedNeurons in the skin can release norepinephrine into fat cells in response to cold, promoting the conversion of white fat to beige and brown fat.

✓Well SupportedWalking outside in cold air activates the sympathetic nervous system, increasing norepinephrine and brown fat.

✓Well SupportedEnvironmental hormetic stressors like sun exposure, cold water, and saunas strengthen the body's antioxidant system.

◐Partially SupportedIndividuals with a genetic predisposition that causes significant stress from cold exposure may achieve adaptive effects from short durations.

◐Partially SupportedCold and heat exposure can lower inflammation, potentially preventing lifestyle diseases like type 2 diabetes, depression, anxiety, and Alzheimer's.

◐Partially SupportedOne individual in a winter swimming study had zero brown fat and was unable to control shivering during a cooling experiment.

✓Well SupportedGoing directly into cold exposure without pre-heating is preferred by some individuals to avoid blood pressure changes.

◐Partially SupportedNaked cold water exposure is considered equivalent to cold water exposure with a bathing suit in terms of physiological effects.

◐Partially SupportedBrown fat is activated by both cold and warming of the skin, suggesting it functions as a general temperature regulator.

◐Partially SupportedInsideTracker's Ultimate Plan includes estradiol, progesterone, and TSH markers for women.

◐Partially SupportedWomen tend to have lower peripheral temperatures, particularly on their hands and ears, compared to men.

◐Partially SupportedCold receptors on the skin signal the hypothalamus to increase neurotransmitters like norepinephrine, adrenaline, and cortisol, leading to brown fat activation.

◐Partially SupportedDeliberate cold exposure, when brief (e.g., 1-2 minutes), is a form of hormetic stress that strengthens cells by challenging them to adapt to temperature changes.

◐Partially SupportedThere are direct pathways from skin cold receptors to brown fat and potentially from muscles to brown fat, indicating multiple mechanisms to maintain body temperature.

◐Partially SupportedFor non-elite athletes, the precise timing of cold plunges is less critical and should be based on personal convenience and effectiveness.

◐Partially SupportedThe cold shock response in cold water immersion can include hyperventilation and gasping, which may subside with adaptation.

◐Partially SupportedWinter swimmers exhibit increased insulin sensitivity and produce less insulin compared to controls.

✓Well SupportedCold exposure on the skin activates brown fat to maintain body temperature.

◐Partially SupportedIncreasing core heat loss by 36% through head dunking in cold water will further increase the 'after drop', bringing one closer to hypothermia.

◐Partially SupportedLocal skin heating provides a potential mechanism for increasing beige fat and overall metabolism.

◐Partially SupportedSympathetic nervous system activation during cold exposure prioritizes blood flow to the heart over the brain to maintain survival.

✓Well SupportedExposing the body to brief periods of toxicity, such as through cold exposure, is beneficial for adaptation and cellular health.

◐Partially SupportedCold water immersion acts as a hormetic stressor, resulting in a net effect of being more relaxed throughout the day.

◐Partially SupportedDipping hands and feet briefly into cold water can still activate the nervous system, even if full immersion is not tolerated.

◐Partially SupportedBrown fat is located centrally under the clavicular bones near the skin surface and can be measured with infrared thermography.

◐Partially SupportedTemperature, specifically heat and cold, can evoke powerful, beneficial physiological changes.

◐Partially SupportedBrown fat, with increased mitochondria, takes up glucose and fatty acids from the bloodstream to maintain thermogenesis, thereby reducing unhealthy white fat.

◐Partially SupportedHealth benefits of cold and heat exposure are achieved by repeated stimulation, not prolonged adaptation.

◐Partially SupportedThe discomfort of deliberate cold exposure is distinct from exercise discomfort and is harder to titrate or adjust.

✓Well SupportedMice housed in cold environments became 40% more sensitive to insulin compared to mice housed at room temperature.

✓Well SupportedBrown fat is an insulin-sensitive organ, and its sensitivity decreases with obesity, potentially explaining lower levels in elderly individuals.

✓Well SupportedShivering burns carbohydrate and is a form of exercise, whereas sustained fat burning occurs when not shivering.

◐Partially SupportedBrown fat is rich with mitochondria, located between the scapulae and in the upper neck, and generates thermogenesis and heat by increasing metabolism and burning fat.

◐Partially SupportedWinter swimmers who stay in the water for one to two minutes experience activation of the parasympathetic nervous system.

◐Partially SupportedCold on the skin activates brown fat.

◐Partially SupportedEnding cold exposure with cold keeps the body working to stay warm, facilitating the core body temperature drop needed to fall asleep.

◐Partially SupportedBabies in Denmark are taken outside to sleep in cold weather to improve their immune system and resilience.

✓Well SupportedDeliberate cold exposure and sauna use are mainstream practices supported by scientific information.

◐Partially SupportedNewcomers to cold water immersion may experience anxiety, elevated blood pressure, and increased heart rate.

◐Partially SupportedAndrew Huberman prioritizes sleeping cool and wearing minimal clothing to challenge thermoregulation instead of regularly doing cold baths.

◐Partially SupportedBiological processes, including metabolic and thermoregulatory ones, are dynamic processes (verbs) rather than static events (nouns).

◐Partially SupportedWomen may require less time for cold exposure per week compared to men due to potentially higher brown fat metabolism and greater cold sensitivity.

◐Partially SupportedExposing cells to potent, stressful situations, such as heat shock, increases heat shock proteins which repair cells.

✕Not SupportedOverdoing heat or cold exposure by exceeding recommended durations can exhaust cells and increase the risk of cardiovascular disease.

◐Partially SupportedRussian Banya and Archimedes Bath House offer hot saunas and cold plunges.

◐Partially SupportedSpa 88 in New York is a facility offering deliberate cold exposure and sauna, where patrons are always clothed.

◐Partially SupportedAcute physiological responses during exercise, such as elevated heart rate and stress hormones, drive long-term adaptations for lower resting blood pressure and inflammation.

◐Partially SupportedAfter age 40, there is an association between decreased brown fat and increased obesity.

✕Not SupportedEngaging in coffee, exercise, or cold water immersion can activate the sympathetic nervous system, leading to a stress response that may make it difficult to fall asleep.

◐Partially SupportedThe water temperature for outdoor winter swimming in Denmark averages around 12°C in October and drops to 2°C in January.

◐Partially SupportedElectromyography (EMG) can measure muscle shivering during cold exposure, and conscious perception of shivering may not be the best indicator.

◐Partially SupportedSome individuals experience headaches at the interface of water and skin during cold immersion up to the neck.

◐Partially SupportedStudies are needed to determine if deliberate cold exposure can offset symptoms in Raynaud's syndrome or autoimmune diseases.

◐Partially SupportedChildren's ability to defend core temperature during cold exposure differs from adults due to their smaller mass and higher surface area to mass ratio.

◐Partially SupportedBrown fat may have evolved to maintain body temperature homeostasis.

◐Partially SupportedMuscles are the second tissue in the body capable of increasing thermogenesis, primarily through shivering.

◐Partially SupportedWomen generally have higher levels of brown fat than men.

✕Not SupportedExceeding approximately 30 minutes in a sauna session does not provide additional health benefits and may increase cardiovascular disease risk.

◐Partially SupportedBiomedical research and medicine are increasingly validating practices like deliberate cold exposure, sauna use, supplements, natural herbs, meditation, breathwork, and psychedelics.

◐Partially SupportedIndividuals who work outside and perform physical labor tend to have more brown fat.

◐Partially SupportedSome humans do not possess brown adipose tissue (BAT).

◐Partially SupportedBrown fat is plastic, meaning it can grow and decrease in size.

◐Partially SupportedReduced exposure to natural temperature variations in a sedentary lifestyle contributes to increased obesity.

◐Partially SupportedA study aimed to establish a continuous measure of brown fat activity in humans and investigate its circadian rhythm.

◐Partially SupportedPET MRI scanning is the gold standard for measuring brown fat activity but is not feasible for most people due to high cost.

◐Partially SupportedHigh blood glucose is neurotoxic and can damage neurons, with insulin buffering blood glucose.

◐Partially SupportedExperiencing cold water immersion for the first time can be painful and uncomfortable, similar to muscle soreness after overexertion.

◐Partially SupportedThe more one avoids cold, the more painful it will feel when encountered.

◐Partially SupportedActivating brown fat increases metabolism.

◐Partially SupportedDr. Søberg's initial research focus was on understanding and lowering sweet tooth cravings.

◐Partially SupportedCold and heat exposure, exercise, and fasting increase hormetic stress in the body.

◐Partially SupportedCold exposure might help individuals with Raynaud's syndrome by improving vascularity and capillary plasticity.

◐Partially SupportedWinter swimmers of all ages can tolerate cold water immersion as if it were nothing.

◐Partially SupportedAdaptation to cold water immersion leads to less vigorous shivering, potentially due to increased mitochondrial density in muscle cells enhancing thermogenesis.

◐Partially SupportedCold exposure is a potential intervention for improving sleep.

◐Partially SupportedOne or two cold water immersions per week can be sufficient to provide energy and a positive feeling.

◐Partially SupportedShivering is a form of training for cells, muscles, and metabolism, improving insulin sensitivity.

◐Partially SupportedChildren and smaller-bodied individuals are at greater risk of hypothermia during cold exposure.

◐Partially SupportedWearing neoprene boots can reduce foot and ankle pain during cold water immersion.

◐Partially SupportedCold exposure training can lead to adaptation, reducing the hyperventilating response and building resilience.

◐Partially SupportedHypothermia can lead to symptoms such as shivering, slurred speech, and semi-euphoria.

◐Partially SupportedWater temperatures as low as 2-4°C are sufficient to activate metabolism.

◐Partially SupportedMen have larger hearts and can pump more blood peripherally than women, potentially explaining why men have warmer extremities.

✕Not SupportedProlonged cold water immersion (e.g., 20-30 minutes) or very long cold showers may be extreme and potentially harmful, accelerating aging.

?Limited ResearchWinter swimmers may activate brown fat, but the optimal stressor level is unknown.

◐Partially SupportedMen are typically thermoneutral at 22°C, while women are thermoneutral at 24°C.

◐Partially SupportedThe range in which neurons are happy and surviving is greater when the body is cold compared to when it is heated.

◐Partially SupportedEnding cold exposure with cold activates brown fat and muscles for hours, boosting metabolism and neurotransmitter activity.

✕Not SupportedPermanent brain cell destruction can occur from prolonged exposure to extreme cold or heat.

◐Partially SupportedEntering cold water feels less stressful if one is warm beforehand, compared to entering cold water when already cold.

◐Partially SupportedIn Scandinavian countries, there is a traditional saying that suggests wearing fewer layers before winter to prepare for the cold and more layers before summer to prepare for heat.

◐Partially SupportedWinter swimmers reported waking up briefly during the night but then falling back asleep.

◐Partially SupportedCold showers are an intermediate cold exposure between being outside in cold air and full cold immersion.

◐Partially SupportedNo studies specifically examine the benefits of deliberate cold exposure in a fasted versus fed state.

◐Partially SupportedA visual analog scale (1-10) was used to assess participants' subjective comfort level with different temperatures.

◐Partially SupportedThe study aimed to identify the lowest effective dose of cold exposure for health benefits.

◐Partially SupportedWinter swimmers report feeling good after cold water immersion two to three times per week, with three dips and two sauna sessions per session.

◐Partially SupportedWinter swimming for 4-5 months in middle-aged men and women is associated with lower blood pressure, heart rate, and better insulin sensitivity.

◐Partially SupportedConsistent cold exposure practice increases brown fat and muscle efficiency, leading to feeling warmer more easily.

◐Partially SupportedCold water immersion up to the neck is more potent in activating the autonomic nervous system than cold air exposure.

◐Partially SupportedTheoretical health benefits of cold exposure suggest one should not over-insulate oneself and should instead engage with the cold.

◐Partially SupportedSubmerging the entire body in cold water, except the head, provides full activation of cold receptors and a complete physiological response.

◐Partially SupportedA winter swimming protocol involves alternating between one to two minutes in cold water and 10 to 15 minutes in an 80°C sauna, ending in cold water.

✕Not SupportedSleeping in warmer temperatures (24°C and 27°C) led to decreased brown fat activation and insulin sensitivity compared to 19°C.

◐Partially SupportedActivated brown fat utilizes glucose and fatty acids from the bloodstream to maintain thermogenesis, thereby clearing sugar and fat.

◐Partially SupportedExposure to natural stressors like cold or heat can reset the body to a state of homeostasis for self-repair.

◐Partially SupportedJumping into cold water when already cold is more shocking to the system than entering from a hot state.

◐Partially SupportedShivering during cold exposure is not a concern as long as one does not become too hypothermic.

◐Partially SupportedWinter swimmers anecdotally report good sleep quality.

◐Partially SupportedThe optimal temperature for deliberate cold exposure is determined by the difference between body temperature and water temperature.

◐Partially SupportedBrown fat activation can help reduce white fat.

◐Partially SupportedThe 'after drop' is when core body temperature decreases after exiting cold water due to blood vessels dilating and warm blood cooling as it circulates to the periphery.

◐Partially SupportedWearing a beanie during cold water immersion, especially in windy conditions, can prevent dizziness by keeping the head warmer and maintaining blood flow to the brain.

◐Partially SupportedWearing clothing during deliberate cold exposure and sauna practices is acceptable and encouraged.

◐Partially SupportedInsulin insensitivity is linked to type 2 diabetes and obesity.

◐Partially SupportedIndividuals lacking brown adipose tissue showed blood markers similar to controls, including higher insulin levels and slower glucose clearance.

◐Partially SupportedExcessive cold adaptation can diminish the health benefits derived from cold exposure sessions.

?Limited ResearchThe idea that cold water and winter swimming activate metabolism is a common belief, but scientific evidence for this is lacking.

◐Partially SupportedPeople in Copenhagen appear to be significantly fitter than those in the United States, evidenced by widespread cycling and swimming in cold harbor water across a wide range of ages.