Cold showers are a new health fad. Internet searches are way up, and you can even find a 30-Day Cold Water Challenge. People are claiming that cold showers are good for everything from depression to losing weight, but, are these claims backed by science?
In fact, yes, many of these claims are supported by research. Fortunately, you don’t have to subject yourself to Scandinavian-style cold water plunges to benefit. Even a minute or so of cold water at the end of your shower may be enough to help you. The actress Katherine Hepburn claimed that cold showers were a key to her high energy, even into her 90s.
Cold showers appear to help since minor stresses force our body to adapt, and in this way, become more resistant to stress (this is called “hormesis”). And, while the research on cold showers is not as plentiful as research on deeper topics like heart disease, some reasonable research has been done. Here are some of those benefits that have at least reasonable research support:
Cold showers— energy, focus, and alertness
The shock of cold water constricts our skin blood vessels, pushing more blood to our deeper organs, and overall improving circulation. Many people find that a cold shower wakes them up better than coffee.
Decreased depression and stress
Researchers have compared brief, shocking cold to the effect mild electroshock therapy for our brain. This shock floods the brain with impulses from our skin and stimulates our sympathetic nervous system. Endorphins, dopamine, and noradrenaline are released, and, after the initial shock, our sense of well-being is boosted. Studies on depressed people have suggested one or two cold showers daily could be as effective as antidepressant medication. Cold water exposure decreases cortisol and uric acid levels, helping relieve stress as well as depression.
Cold showers boost metabolic rate
The cold forces our metabolic rate to speed up to stabilize our body temperature. The cold also stimulates the activity of “brown fat”. This type of fat is present in small amounts in a few areas of our body, and is totally different than white fat. Having stimulated, active brown fat is a good thing, and it generates heat which keeps us warm when we are challenged with a cold stimulus. One study showed cold exposure stimulates brown fat activity by a factor of 15, which can, over time, help weight loss. While daily cold showers alone are not a weight loss strategy, it can help.
The intense skin stimulus triggered by the cold blocks pain receptors, similar to the action of acupuncture. The showers can especially help chronic pain disorders such as fibromyalgia and rheumatic arthritis.
Improved immune response
Cold showers shock the body, which, to protect itself, increases production of cytotoxic T lymphocytic immune cells and white blood cells. This is not seen after hot showers. So cold showers may toughen your body immunologically, and decrease your chance of viral infections. Some research suggests cold exposure may even increase your resistance to certain cancers.
Improved skin and hair
Cold showers are much better for your hair and skin than hot showers, which can aggravate skin conditions such as eczema, and contribute to dry skin. Cold showers help flatten the hair cuticles, and help the skin and hair keep their natural oils to give shinier, fuller hair and more moisturized skin.
Shower temperature and time
The suggested water temperature is 20 degrees or less. You don’t have to take the whole shower in cold water, but at least avoid hot water showers, even though they feel good in the moment. You can start with a moderate temperature shower, then finish with at least a minute—but preferably 2 to 3 minutes—of cold water. Try it for a week, and see how you feel! Avoid cold showers if you are pregnant, and if you have heart problems, check with your doctor first.
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