AMA #7: Cold Exposure, Maximizing REM Sleep & My Next Scientific Studies
Huberman Lab Podcast Recap
Published:
Duration: 32 min
Summary
This AMA episode focuses on the effects of deliberate cold exposure on health, specifically in relation to sickness and immune function. Andrew Huberman emphasizes that while cold exposure can boost immune markers, doing it when sick might not be advisable.
What Happened
Andrew Huberman addresses whether deliberate cold exposure can cause sickness. He notes that brief exposure, followed by warming up, is unlikely to lead to illness, though he advises against starting with long exposures, especially for those unaccustomed to it.
Huberman explains that cold, dry air can increase susceptibility to viral and bacterial infections by drying out mucosal linings in the nose and mouth. Breathing through the nose is recommended to reduce infection risk, as the mouth is a common site of entry for pathogens.
He advises against cold exposure when feeling unwell due to a cold or flu, suggesting warm baths or saunas instead, but warns against overly hot environments, which could stress the body. Huberman differentiates between the effects of deliberate cold exposure and chronic stress on the immune system.
Deliberate cold exposure can enhance immune markers if done correctly and regularly, although this enhancement isn't guaranteed to improve resistance to specific pathogens. Huberman refers to studies showing trends in increased immune cells with regular cold exposure.
He discusses a study on cyclic hyperventilation, which increases norepinephrine and epinephrine, potentially suppressing some immune responses. This can reduce symptoms during bacterial infections but doesn't necessarily prevent the infection itself.
Huberman emphasizes that while cold exposure and hyperventilation can increase immune function markers, overdoing them can have the opposite effect. He advises using these methods when healthy but suggests avoiding them during illness to allow the body to rest and recover naturally.
Key Insights
- Deliberate cold exposure lasting one to ten minutes, followed by warming up, is unlikely to cause illness. This practice can potentially increase immune markers if done regularly.
- Cold, dry environments can increase susceptibility to infections by thinning the mucosal lining in the nose and mouth, especially when breathing through the mouth.
- Huberman advises against cold exposure when feeling unwell, recommending warm or hot environments instead, but warns against extreme heat that can stress the body.
- Cyclic hyperventilation, like deliberate cold exposure, can release epinephrine and norepinephrine, impacting immune responses by suppressing symptoms rather than preventing infections.