One of the hottest trends of 2024 is ice cold.
Social media influencers are touting ice plunges – the practice of regularly immersing yourself in uncomfortably cold water as a natural way to ward off a myriad of ailments including inflammation, obesity, anxiety, and depression.
With winter approaching – and popular polar bear plunges planned, including in Asbury Park on Jan. 1 and Seaside Heights on Feb. 22 – we checked in with Steven Malin, associate professor in the Department of Kinesiology and Health at Rutgers-New Brunswick’s School of Arts and Sciences to learn more about the pros and cons of ice plunges.
Ice baths/cold plunges are trending with health influencers right now. Do you know when and how this trend got started?
It seems like a craze now, but this has been done throughout the ages. There are documents going back to Hippocrates, the father of modern medicine, Darwin, Thomas Jefferson, and others that show them using cold plunges as a ritual of sorts. I think now it’s come back into vogue.
A few years ago, there was a lot of interest in the biological sciences about activating brown fat, which is a type of body fat that is not very common in adults and much higher in babies. Its main function is increasing heat production in the body through higher metabolic rates.
Since cold activates brown fat, there was interest in seeing whether cold exposure could stimulate the body’s metabolism.
There were a few studies in humans and rodents that found it can be true. But the number of calories burned range from 20 to 50. To put that into perspective, a regular Oreo cookie is 50 calories. So that is not a lot.
Then what are the benefits of cold plunges? We've heard they can help reduce everything from inflammation to anxiety and depression. Is that true?
In the athletic realm, cold therapy isn’t novel. It has been used for decades to treat injuries by reducing inflammation. The connection to mental health comes from the idea that cold plunges may increase dopamine response along with epinephrine and other hormones like endorphins that can improve mood. The research on this is mixed. For some people, cold response does provide some of these mental health benefits. Whether that’s a true effect or placebo effect, we are not sure.
We don’t have randomized human trials to determine whether cold plunges are an effective modality to treat anxiety and depressive disorders. Assuming a person is healthy and cleared by a doctor, it may not be a bad idea to try it and see if it works for them.
I would look at it like having another tool in your toolbox to promote a stimulus in our body – just like exercise. You may be deriving some of the same benefits from exercise. Even heat therapy can be another tool to achieve similar outcomes.
How cold does the water need to be? How long of a plunge do you need to take?
Somewhere between 50 and 70 degrees is the suggestion. Going much lower than 50 starts to pose risks. It can be painful, promote hypothermia, elevate heart rate, blood pressure and breathing rates and that could be problematic – especially for someone with underlying issues.
For time, 5 minutes or no more than 10 has been my understanding. But if you are new to it, I would start with a lower time and gradually increase to avoid risks.
Are there people who should avoid cold plunges? Why?