"Humans have used cold exposure, often with the expectation that it promotes health, for centuries."- Dr. Rhonda Patrick Click To Tweet

Conventional wisdom tells us to bundle up, stay warm, get comfy – and avoid stress. But is that really a good idea? Perhaps stress – in this case, stress from cold exposure – is exactly what we need.

In this video I discuss:

• 00:00:51

  Benefits of norepinephrine
• 00:01:18

  Benefits of mitochondrial biogenesis
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  Types of shivering
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  Activation of brown adipose tissue
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  Metabolism and energy expenditure
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  Vigilance, mood, and attention
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  Tips for using cold stress
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  Concluding thoughts

Orchestrating the body's response to cold, norepinephrine is a key player.

The body's response to cold-water immersion and similar cold-exposure techniques like cryotherapy is a robust release of norepinephrine, rapidly setting off a cascade of adaptive effects that influence aspects of metabolism, brain function, and genetic expression. As result, regular, whole-body cold exposure may exert systemic beneficial effects, improving glucose and lipid metabolism, decreasing inflammation, improving cognitive performance, and potentially enhancing immune function – critical aspects of maintaining health in our modern world.

These beneficial effects of cold exposure may be due to hormesis, a favorable biological response to a mild stressor. Hormesis triggers protective mechanisms that provide protection from future, more harmful stressors.

Other hormetic responses to cold exposure include increased production of PGC1-alpha, a protein that promotes mitochondrial biogenesis, the production of new, healthy mitochondria, and the activation of brown fat – a phenomenon once thought to occur only in newborns, but now known to occur in adults, especially after cold exposure.

Establishing a cold exposure protocol: temperature and duration

"Cold" is a relative term, so to reap the benefits of cold stress, it's important to consider how cold and how long the exposure is, as well as the method. Hour-long exposure to neck-deep cold water (57°F, 14°C) increased norepinephrine by 530 percent and dopamine by 250 percent. But a 20-second whole-body dip in very cold water (40°F, 4.4°C) increased norepinephrine 200 to 300 percent. And other research has shown that frequent exposure to cold air at more moderate temperatures (63°F, 17°C) promoted body fat loss, although the losses were neglible.

The science of cold exposure is young, and many questions remain, but a growing body of evidence suggests it may offer many health benefits. Of course, exposure does pose some risks, especially in unsupervised or uncontrolled conditions, so be sure to review cold-water safety concerns in our overview article.

Learn more about cold exposure

Topics

• Cold exposure – topic overview page on the hormetic benefits of cold exposure.
• Whole-body hyperthermia – a different temperature modality currently being investigated for depression

Episodes and clips

• How Cryotherapy Affects the Brain, the Immune System, Metabolism, and Athletic Performance – an audio-only podcast discussing some of the benefits of cold exposure
• Wim Hof (the Iceman) on Defeating Extreme Cold & Attenuating the Immune Response – Wim Hof, a world record holder for a variety of extreme cold activities, talks about some of his life experiences that led him in that pursuit