Ice, Ice Baby: The Surprising Benefits of Cold Water Exposure

Years ago, when I first heard about "The Polar Plunge" I remember how crazy it seemed. I thought it must just be some Canadian retirees looking for a little excitement up there in the frozen North. Later I learned that cold water immersion was standard practice among athletes seeking to reduce inflammation, injury, and recovery time. Since, however, I am neither Canadian nor athlete, I have never been tempted to explore this frigid exercise for myself... Until now.
There is a growing body of research that suggests there are a wide range of surprising physical and mental health benefits from regular cold water exposure. Scientists are now discovering that regular brief cold immersion can effect everything from disease to depression, Alzheimer’s to anxiety, mortality to overall mental health. It’s got me thinking more seriously about taking the plunge.

So Many Health Benefits
Mood. I find one of the most striking benefits of cold water exposure is its ability to reduce depression and improve mood. Some studies suggest that in some cases it can be as effective as anti-depressant medication. This is, in part, the result of how cold immersion triggers the release of endorphins, adrenaline, and dopamine. These neurochemicals reduce pain and boost energy - physically and mentally - combating fatigue and other symptoms of depression.

Stress. Despite the adrenaline-inducing initial shock of cold water exposure, it does not trigger increased cortisol. Cortisol is the body's primary stress hormone that correlates with stress, panic, and various anxiety disorders. In fact, cold immersion appears activate the body's Vagus nerve, inducing a nervous system shift from sympathetic to parasympathetic. It's an interesting neurological cascade that results in a surprisingly long-lasting state of enhanced emotional calm, reduced anxiety, and increased mental flexibility.

Mental sharpness. Cold water exposure increases blood flow to the brain. This increased oxygen, along with with the low cortisol and elevated epinephrine, norepinephrine, and dopamine, boosts cognition, concentration, memory, and motivation. It's an effect similar to what many ADHD medications do, enabling a person to set and achieve goals more easily and with greater creativity.

Sleep. Sleep is foundational for physical and mental health. Lack of quality sleep leads to anxiety, depression, illness, and increased mortality. Cold water exposure improves sleep quality by increasing the efficiency of melatonin production, a hormone that helps to regulate sleep.

Energy. In addition to the release of excitatory neurochemicals, cold water exposure increases the body's metabolism, converting fuel stores for warmth. This, with the an overall increase in blood circulation, boosts energy in both the short-term and long-term. One study found that regular cold-water immersion after exercise resulted in improved baseline muscular blood flow, increasing strength and stamina.

Inflammation. Cold immersion reduces every form of inflammation, including inflammation in the brain. Studies have correlated brain inflammation with increased risk of depression, anxiety, psychosis, and Alzheimer’s. With this, cold exposure combats inflammageing, an age-related increase in pro-inflammatory markers contributing to prevalent diseases among older adults, including heart disease, diabetes, Alzheimer's, and cancer.

Pain. If you've ever experienced chronic pain, you're aware of what a significant impact it can have on a person's mental health. Cold water exposure reduces pain through multiple mechanisms that interrupt and subdue neurological pain signals.
Johanna Nordblad is a Finnish designer and now ice diver who shattered her leg in a biking accident. The nerves were so badly damaged that, even with medication, her pain remained profound and persistent long after recovery. Her doctor eventually suggested trying cold exposure. Nordblad explains, "The first time I put my leg in 4°C water I only managed to keep it in for a minute, but the relief was immediate. Finally, it didn’t hurt any more.”

Immune system. Cold water exposure has been shown to boost the immune system, in part by increasing the body's production of white blood cells. This helps to prevent illness and infection that, like pain, negatively impact mood when experienced frequently or persistently.

How Cold, How Long?

As a health provider, I'm all about that healthy-habit lifestyle. As a life-long desert dweller, however, I find myself looking for the minimum cold-induced suffering necessary for these health benefits. Fortunately, there appear to be a number of measurable health gains from just 30 to 90 seconds daily in 50°F to 60°F water. A famous landmark study in the Netherlands found that ending a daily shower with 30 seconds of cold can reduce illness by nearly 30%.

While there do appear to be some increased benefits from longer durations of cold exposure (to a point), studies suggest that the colder the water - the less time you need. Encouragingly, the brain and body become increasingly cold tolerant with regular exposure, making the whole experience a bit easier over time. For me, all this has translated to the last 30-60 seconds of my shower ending with the faucet all the way on "cold". Yes, there is still some mild cursing and a lot of rapid breathing involved, but I’ve found that it's slowly getting easier.

It's important to be aware of any health risks cold water exposure may present for you before jumping in. But if you're interested, why not join me and take the plunge? Your body and brain will thank you for it (eventually)!