Are the supposed benefits of cold showers compelling enough to convince you to turn the faucet the other way every morning?
Cold shower benefits science
Many claim that taking a daily cold shower can have health benefits: improving circulation, relieving stress and increasing vitality and alertness are some of the benefits most attribute to this habit.
But it is also said that it can help treat depression and anxiety, repair muscles after exercise, burn more fat or even give a boost to the immune system.
Are there scientific studies to prove it? And if so, are those supposed benefits strong enough to convince you to turn the tap the other way?
To begin with, what is clear is that cold water, on contact with the skin, is a shock to the body: the body reacts by triggering a massive stress response, which causes the heart rate to rise, blood circulation to increase and adrenaline to be released.
On the other hand, at the household level, a cold shower is quite safe and – shudders aside – has no significant negative health effects.
Unless you are very old or have heart problems, in which case the cold water could cause you to faint or have a heart attack, says Dr. Chris van Tulleken, host of the BBC’s “Trust me, I’m a doctor” program.
Against depression and anxiety?
Although there has not yet been a clinical experiment using cold shower therapy as part of the treatment for depression and anxiety, some experts believe it can help.
The theory behind it is that repeated exposure to cold water makes the body better able to deal with the stress response and chemical and hormonal changes that people with depression feel.
They also argue that adapting to that repeated exposure to the stress of cold can help us cope better with the psychological stress that often accompanies anxiety.
In a 2013 TED Talk, triathlete Joel Runyon argues from a personal perspective that taking a cold shower can change the way you cope with fear and how you deal with situations in which you feel uncomfortable.
Another hypothesis argues that given the large number of cold receptors in the skin, a cold shower causes the brain to receive an enormous amount of electrical impulses from peripheral nerve endings, which may have an antidepressant effect.
For the immune system?
According to Chris van Tulleken, for now there is no definitive evidence on this benefit.
But a Dutch study on the effect of cold showers on health and work published in 2016 in the journal PLOS One found that a daily cold shower resulted in a 29% reduction in participants’ self-rated illness during the 90 days after adopting that habit.
For at least 30 consecutive days, individuals were required to take cold showers at the end of their usual hot showers, for periods of 30, 60 or 90 seconds, depending on the study subgroup.
The researchers found that the duration of the cold shower did not influence the results, so fortunately 30 seconds is sufficient.
The beneficial effect most noted by the volunteers was an increase in perceived energy level, which many compared to the effect of caffeine. In fact some continued to take a final shower with cold water beyond the 30-day minimum period for the experiment.
On the other hand, the most reported moderate adverse effect was a persistent feeling of coldness in the body, hands and feet.
For muscle soreness after exercise?
Many athletes are proponents of cold water baths after exercise.
The theory behind this habit says that soaking in cold water reduces soreness and speeds recovery from small tears in the muscles generated by exercise.
But the scientific evidence on whether or not this works is mixed.
Some studies say it improves recovery but others suggest it may reduce the muscles’ ability to adapt.
On the other hand, a 2014 study published in Physical Therapy in Sport found that there was no significant statistical difference between taking a single brief contrast dive, intermittent brief hot and cold water dips or 10-minute dips in cold water at 6 or 10 degrees.
Do Cold Showers Really Help Burn Fat?
This is one of the most popular beliefs about cold showers: that it can turn unhealthy “white” fat into metabolically healthy, active “brown” fat.
Unfortunately, says Tulleken, there’s very little evidence that this is true.
According to Dr. Tulleken, so far the scientific research on the benefits of cold shower therapy is still at a very early stage and there is not much conclusive evidence.
But since there have been no significant adverse effects reported, other than feeling cold, nor is it something that causes dependence, if someone feels they are working for them there is no reason to stop doing it, Tulleken suggests.
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- Scientific Evidence-Based Effects of Hydrotherapy on Various Systems of the Body: https://www.ncbi.nlm.nih.gov/pmc/
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