Submerging your body in ice-cold water may not be everyone’s first thought as a mental health booster. Over the years, cold water exposure or cold water immersion (CWI) has become exceptionally popular. This technique entails submerging your body, up to your neck, in water colder than 15 degrees Celsius for about two to three minutes at a time. With its popularity, numerous health benefit claims have surfaced such as CWI’s ability to boost the immune system, treat depression, enhance peripheral circulation, increase libido, burn calories, and reduce stress levels (Hsaio, 2020). Further, several other studies give specific scientific insights on how cold exposure or CWI boosts health. These studies suggest that regular cold exposure can be effective in the treatment of chronic autoimmune inflammation (Leppaluoto et al., 2008), reduce hypercholesterolemia by brown adipose tissue activation (Berbee et al., 2015), and have a positive effect on stress regulation (Leppaluoto et al., 2008). However, what is less clear are the direct effects of cold exposure on mental health. Does CWI have the ability to treat depression, anxiety, or other mental health conditions? And further, is there rigorous scientific evidence that supports this? Or is this more of a correlation, or a placebo effect?
Numerous studies and reports have expressed the benefits of CWI on mental health. However, the majority of these studies use participant self-report questionnaires to gauge effectiveness. There are several other biases that need to be taken into consideration.
One can argue that individuals who are partaking in CWI or ice swimming are naturally living more active lifestyles, which correlates with positive mental health scores. Perhaps these individuals are “beginning” with less chronic mental health concerns than their counterparts, making mental health management easier. Secondarily, it can be argued that individuals who choose to engage in CWI are more focused on health and wellness. Could this possibly create a self-fulfilling prophecy leading to better mental health?
Openness to experience
CWI can be a stressful and unpleasant experience or thought. Submerging one’s body in ice-cold water doesn’t exactly give us warm, fuzzy feelings. However, many individuals claim to actually have very pleasant encounters and enjoy their cold water baths. It can again be argued that individuals who choose CWI have higher levels of openness. According to the five-factor model of personality, or simply The Big Five, people with high levels of openness are more likely to seek out a variety of experiences, be comfortable with the unfamiliar, be more intuitive, and enjoy surprise and curiosity. One study by Carrillo et al. (2001) found that individuals who score high on openness to action (such as CWI) are negatively correlated to depression, but high scores on openness to fantasy seem to be a predictor of depression.
What Does the Research Say?
Although these individual differences or biases may be a factor in self-report data, there does seem to be some specific scientific evidence for the benefits of CWI in managing depression and positively supporting mental health. According to research by Shevchuk (2008), increases in plasma noradrenaline, beta-endorphin, and synaptic release of noradrenaline in the brain due to stress induced by CWI may have a positive effect on mental health and brain development. Further, one interesting case study by Van Tulleken et al. (2018) describes a 24-year-old woman with depression and anxiety who undertook cold-water swimming and, after four months, no longer required medication. It is thought that the “shock response” from immediate exposure to cold water can act like an internal reset button for our neurotransmitters, while subsequently giving us a boost of norepinephrine.
Finally, it’s important to discuss the role of breath. Many cold-exposure gurus, such as the infamous Wim Hof, discuss the importance of breath training in conjunction with cold exposure. Deep breathing can help override the instantaneous shock response that results in hyperventilation when exposed to cold water. In a study by Perciavalle et al. (2016), research supports the possibility that deep breathing techniques are capable of inducing an effective improvement in mood and stress both in terms of self-reported evaluations (MPS and POMS) and objective parameters, such as heart rate and salivary cortisol levels.
CWI in the Treatment of Addiction
The idea of CWI has also become a hot topic for the treatment of addiction or substance use. Numerous boutique treatment centers are now beginning to offer cold water therapy in the treatment of addiction. Dr. Lembke, who was recently featured on a popular podcast, explains that addiction is a “bio psycho social disease” and activities that give you longer-lasting dopamine spikes are less likely to lead to tolerance and addiction, such as CWI. Lembke explained that when you deliberately do things that are difficult, shocking, or intimidating, your body creates natural dopamine to make you feel better. This is also a longer-lasting, sustained dopaminergic response. Conversely, when you do (or take) things that make you instantly feel good and give you an artificial rush of dopamine, such as drugs, your body stops making/up-taking dopamine to compensate, ultimately making you feel worse and needing more. This can lead to interesting follow-up questions such as whether one could start to require more time in the cold water to achieve the same dopaminergic response.
Overall, CWI does seem to show some promising results in its ability to positively impact mental health. Whether it’s personality traits or lifestyle choices, self-fulfilling biases, or objective scientific data, perhaps it’s worth a dip if you dare. As a precaution, consult with your physician first to make sure it’s safe for you. And always remember, icy does it!