Anybody having ice-cold showers in the dead of winter and here I’m taking about myself and any other self-immolators would only endure such torture after witnessing Dutch extreme athlete Wim Hof, AKA ‘The Iceman,’ resist the onslaught of a slew of viruses hurled at him by an array of scientific sceptics doubting that cold exposure was of any benefit. If he could also climb Mount Kilimanjaro in shorts, run a half marathon above the Arctic Circle barefoot, stand in a container while covered with ice cubes for more than 112 minutes and be so empowered then surely our immune systems would enjoy some enhancements if we subjected ourselves to a modicum of similar suffering.
Cold-water swimming is now embraced around the planet as an exacting pastime worth pursuing by those who claim to suffer fewer and milder respiratory infections but very few studies have been carried out to support this.
In those not used to the cold, initial head-out cold-water immersion at a water temperature below 15 °C can be dangerous provoking hyperventilation, a fast heart beat and raised blood pressure. This initial cold rush ignites hormones which transiently tamps down the body’s immune capabilities rendering us more vulnerable to infections. One study has demonstrated that although this might happen in younger people it did not result in an increase in the common cold after 48h hours. As this was a one-off event the experiment did not examine what delayed effects either good or bad this might have had.
In another study winter sea bathing was associated with lower levels of self-reported stress and higher wellbeing. There was no increased risk of respiratory infections and in fact those who engaged in this activity had significantly higher levels of a compound called salivary sIgA, known to bolster the immune system.
Chilean army personnel repeatedly exposed to cold water experienced an increase in immune cell numbers. Another has shown that cryotherapy which involves exposure to a blast of nitrogen also mobilises the immune system making the recipients more resistant to getting infections. In those suffering from emphysema frequent cold exposure reduced the incidence of winter respiratory infections.
Even though the results are a little conflicted the weight of evidence seems to suggest that cold water therapy might in the long run boost our immune systems so I’m going to continue that hopefully ultimately rewarding invigorating shower experience.