Millions of Americans might think a cold shower could help them cope as temperatures hit dangerous heights this week – but experts warn that it could do more harm than good.
While the cold water may provide a feeling of relief, the body may not actually be cooling down, Adam Taylor, a professor of anatomy at Britain’s Lancaster University, explained in The Conversation.
Instead, you may risk circumventing the built-in mechanisms that help humans to cool down. For example, when we get too hot, the brain instructs blood vessels to widen and allow more blood to flow closer to the surface, which in turn cools us down. But, when exposed to the cold, those blood vessels near the skin contract and blood flow is reduced.
“So in the context of cooling the body down, jumping into a cold shower does the opposite of what needs to happen, as less blood is now flowing to the surface of the skin. This will hold the heat in and around your organs instead of getting rid of it,” he explained. “Basically, you’re tricking your body that it doesn’t need to cool down, but actually needs to conserve heat.”
That’s not the only thing you may need to worry about. You may unwittingly trigger a cold shock response.
That can cause dramatic changes in breathing, heart rate, and blood pressure.
“This causes the blood vessels in the skin (those in contact with the cold water) to constrict rapidly. This increases blood pressure as the heart is now pumping against increased resistance,” said Taylor, noting that it may prove especially dangerous for people with coronary artery disease and other underlying heart conditions.
The cold shock response can raise the risk for stroke and heart failure, potentially even leading to death, according to the National Center for Cold Water Safety.
A cold shock response in people going from hot temperatures into cold showers is rare, however.
But, there are also potential benefits to just taking a cold shower, right?
UCLA Health says research has found they could bolster your immunity to common colds, improve circulation, reduce inflammation, and increase metabolism. The Cleveland Clinic also explains there could be similar benefits. But, both warn about the impact of cold shock, and urge people to be aware of the symptoms.
“These may include intense stress or fear, gasping, difficulty breathing, rapid heart rate or dizziness. If this happens, end your shower and warm up,” Cleveland Clinic family medicine physician Dr. Christopher Babiuch said.
Heart experts have warned against cold water immersion for anyone with an underlying condition, as not enough research has been done.
“I would caution against it for anyone with a cardiac history,” Dr. Jorge Plutzky, director of preventive cardiology at Brigham and Women’s Hospital, said.
