Can cold water actually stop you from getting sick?

In the largest study of its kind, with over 3000 participants, researchers found that people who practice deliberate cold water immersion are 54% less likely to call in sick to work. There are many more studies like this that link cold water exposure to improved immune function, but what’s actually happening inside the body to stop you from getting ill?

The key to understanding how our body's immune system interacts with the cold starts with the spike of norepinephrine and epinephrine (noradrenaline and adrenaline) that is released when we get into an ice bath. The sudden release of these two chemicals stimulates the production of immune cells like Interleukin 6, T-Lymphocytes, and B-Lymphocytes, all of which correlate with improved overall immune function.

These effects were first recorded in a study published back in 1996 when participants were put in 14-degree Celsius water for 60 minutes at a time, and then their blood was analyzed. They discovered the trends between norepinephrine and epinephrine release with elevated levels of immune cells and immune molecules.

The triggering of these immune cells and immune molecules makes us more resistant to bacterial or viral infections. These responses were recorded in the famous ‘Wim Hof’ study, where participants combined deliberate hyperventilation and cold water exposure to spike their levels of norepinephrine and epinephrine before being injected with endotoxins that would infect them with the flu. The control group got sick, really sick, vomiting and diarrhea sick. Those who had artificially activated their immune system didn’t, or avoided any significant symptoms.

However, it’s important to note that chronically elevated levels of both norepinephrine and epinephrine can be detrimental to immune function in the long term. Consistent overexposure to these chemicals, especially elevated levels later on in the day, can actually harm immune system function.

So if you’re looking to use cold water exposure to enhance your natural immunity, time them early on in the day and don’t overdo it. It’s important to remember as well that if you’re already feeling quite sick, it’s too late - let your body focus its resources on healing you rather than further adapting to external stressors.