According to an article published by American Heart Association News, jumping into icy cold water in the dead of winter might seem like a crazy idea, but the so-called polar bear plunge has become a popular activity, often paired with raising money for charity.

Boosting its allure is another anything-but-hot trend, the practice of cold therapy, based on the belief that exposing the body to cold water and air may strengthen the immune system and improve cardiovascular health. Actor Chris Hemsworth of “Thor” fame helped promote the idea when he took an Arctic swim without a wetsuit as part of National Geographic’s “Limitless” television series.

But evidence supporting the health benefits of cold therapy remains scant. Experts caution that for some people, shocking the body with cold water could do more harm than good, even at less-than-frigid temperatures. The National Center for Cold Water Safety warns that sudden immersion in water under 60 degrees Fahrenheit can kill a person in less than a minute.  Read full article