5 myths about cold water exposure

Cold showers. Being on an army base comes to mind, or possibly prison. Either way, cold showers tends to conjure up a punitive element. People who take cold showers willingly when they actually have access to hot water? Well, they must be masochists, or else oddly inured to ordinary human sensation. Or a bit mad.

But science is proving something that humans (and probably lots of animals) too have known since time immemorial; that cold water is an amazing tonic for the body and mind, and yes, you can get yourself to the point where not only do you no longer mind the cold, you actually look forward to it.

Understanding how to recruit the Vagus Nerve is a significant step towards calming the sympathetic fight and flight response and engaging the tend and befriend response of the parasympathetic pathway. The science on the subject is growing fast, and we now have several to reference that demonstrate cold exposure to improve ‘vagal tone’, a key metric of a healthy and responsive nervous system and is adaptive and resilient to stressors.

Vagal tone is measured through the physiological phenomenon of heart-rate variability (HRV). HRV refers to the differences in length of time between our heart beats. A healthy heart does not keep perfect military band rhythm. Surprising as it may seem, it is actually healthier to have slight differences in the interval lengths of your heartbeat. The interval between beats becomes shorter when we breathe in and longer when we breathe out, for example, a feature called respiratory sinus arrhythmia (RSA). HRV is largely influenced by Vagus Nerve activity; and cold exposure is one bottom up (body-first) approach to engaging the Vagus Nerve. This is why cold showers in moderation can be good for the heart among many other things.

Various research has shown that regular cold water exposure:

  • improves mood, even combating serious depression
  • increases alertness and concentration
  • boosts the immune response
  • reduces inflammation
  • improves insulin sensitivity thus reducing the risk of diabetes
  • improves cardiovascular health
  • helps to combat stress
  • helps to burn fat
  • increases circulation
  • improves the condition of the skin
  • promotes healing of muscle injuries

But there are several myths about cold water exposure. As someone who took A LOT of convincing to even try cold water exposure, I know how these myths stood in the way of taking the plunge and reaping the many benefits that this simple, cheap and effective intervention has to offer.

Myth 1: The whole shower must be cold.

I never take a cold shower. But I regularly take cold ‘rinses’. This means that I take a hot shower first to wash and scrub and then I turn the dial to cold and use the nozzle for very targeted exposure on certain parts of my body. This is very different and far more tolerable than stepping directly into cold water.

Myth 2: You need to be shivering cold

No, you don’t. I never go so far as to shiver because it is not necessary for the water to be freezing cold. Science has shown that you don’t need to go under 68 F/20 C to reap many of the benefits discussed here. This is equivalent to cold pool water. You can start with a warm rinse, and then each day adjust to go just a little bit colder. I never measure the temperature of my cold rinses, I just turn the dial to the cold. Strangely, I find it easier to take cold showers in the winter rather than the summer. Maybe this is because I have the heat on in the bathroom.

Myth 3: You need stay under for several minutes.

Even two or three minutes is enough. One study in the journal Medical Hypotheses found that participants who took regular two-to-three minute cold showers of 68 degrees over a two-week period found that their mood measurably improved.

Myth 4: You need to stand under the water

I was very resistant to taking cold showers, even as ‘rinses’ in the beginning. I had a particular aversion to the idea of putting my head under the cold water. I was happy to learn that this is actually not necessary, and in fact, targeted cold-water exposure with a shower nozzle can be even more effective than immersing yourself completely.

The ‘targeting’ part turns out to be key. Cold water exposure increases blood flow to deep tissue and so can help to repair damaged muscles because your blood contains nutrients that heal. Focus the spray on the area that’s aching or giving you trouble. This technique helped me enormously while I was healing from a sacroiliac joint problem that was giving me pain in the hips and lower back.

Research carried out by the Institute for Health and Behaviour at the University of Luxembourg found that cold exposure specifically targeting the sides of the neck and the cheeks of the face was effective in stimulating Vagus Nerve activity as measure by heart rate variability.

Myth 5: You will feel colder when you get out

Actually, you will feel warmer. Try it for yourself and see. Take a normal shower, and notice your body temperature before you step into the shower stall, and again when you get out. The next day, add a cold rinse to your routine and again pay attention to your body temperature. You will notice that you feel warmer after the shower than when you went it. And this increased warmth can stay with you for hours. The reason you feel warmer after a cold shower is because cold increases our core temperature through increased circulation. Increased circulation is one of the top reasons experts recommend cold showers. As cold water hits your body, it constricts circulation on the skin surface. This causes blood in your deeper tissues to circulate at faster rates to maintain ideal body temperature.

Below are links to several studies on more benefits of cold exposure:

Improved mood

Cold water swimming has been shown to combat major depressive disorder

Improved insulin sensitivity

Cold exposure reduces insulin resistance, and so reduces the risk of diabetes

Combating stress

A study found that participants who swam in ice-cold water on the regular showed an increased tolerance to stress—all thanks to their bodies adapting to the repeat exposure.

Improving the condition of the skin

Hot water actually strips natural oils from the skin and dries it out. Cold water helps to condition the skin. It constricts blood vessels which tightens pores, protecting against pollution and helping to maintain the skin’s firmness and hydration.

Burning fat

Cold showers jumpstart your metabolism and may help with weight loss by increasing the activity of brown fat, a special type of fat that produces heat and burns calories when the body gets cold.

Boosting the immune system

There are many studies on the connection between cold exposure and an enhanced immune system. Taking a cold shower increases the number of white blood cells in your body, the cells that protect you against diseases.

A fascinating clinical trial in the Netherlands found that cold showers led to a 29% reduction in people calling off sick from work.

Another study connected cold showers to improved cancer survival.

So, in short there are many reasons to be bold with cold. And you will feel like a superhero, I promise you!

Recruiting the Vagus Nerve 4: the practice of gratitude

Did you know that the simple act of counting your blessings is actually powerful medicine. that can make measurable changes to your body? The practice of gratitude has been scientifically proven to not only positively affect our psychological health but also improve numerous physiological markers.

This series is about showcasing all the methods I’ve learned that have been proven by science to target the Vagus Nerve, many of which have been practiced for millennia by practitioners of different spiritual and philosophical traditions. What all of these practices do is to improve what neuroscientists call ‘vagal tone’ – that is, our ability to adapt and shift our nervous system responses in a way that is appropriate to the actual level of threat or safety in the environment. Poor vagal tone results in us under-estimating or over-estimating a particular threat and thus generating a nervous system response that is either too passive or too active.

There are both ‘bottom up’ and ‘top down’ approaches to recruiting the Vagus Nerve to improve vagal tone. Bottom up approaches are those that directly work on the body. Top down approaches start with the mind. Both can be effective because the fibres of the VN are both efferent and afferent, meaning that they send information from the brain to the body and to the brain from the body.

Practicing gratitude is a top-down practice that has been proven to improve vagal tone. This may seem surprising, since gratitude is thought of as simply an emotion, but if neuroscience is teaching us anything it is that the mind/body system is reciprocal. Remember that the Vagus Nerve is the connection pathway that comes into play when the nervous system receives signals that the body is safe. When we experience the feeling of gratitude, we feel safe, because gratitude is a feeling of abundance, that counteracts feelings of lack or scarcity. In fact, we cannot truly feel gratitude unless we feel safe to some degree because gratitude is an emotion that requires a certain openness and relaxation. It is a connected emotion – that calibrates us to our less egocentric Self and tunes us in more with the people and environment around us.

Dr. Stephen Porges, who developed the Polyvagal Theory that I discuss in this series, says that practicing gratitude actually generates all kinds of neurochemical changes that signal the brain that you are safe and therefore available to vagal activity. And so gratitude is protective in the sense that it protects us from falling into negative states that are anxiety or fear-driven.


A practice of gratitude has been shown to reduce doctor’s visits, improve cardiac function, improve sleep and decrease inflammation while also lifting mood, alleviating depression, and increasing optimism and an overall sense of well-being. Scientists have discovered that the more you practice gratitude, the more you can maintain a positive outlook.­­ In a study conducted by Harvard Medical School, after only two weeks of a daily gratitude practice, participants reported feeling more hopeful, that they appreciated their life more, and could deal better with everyday challenges.

Another study followed the reports of participants who kept a daily gratitude journal. They reported feeling 15% more optimistic, experienced a 25% improvement in sleep quality and were overall 10% happier, which apparently is the same increase in happiness you get from doubling your income.

The National Institute of Health in the US performed a study using MRIs to show that subjects who focused on gratitude had an increase in blood flow to the hypothalamus-the almond-size part of your brain just above your brainstem that controls stress and sleep. Enhanced activity in this part of the brain inhibits the stress hormone, cortisol, known to increase heart rate and blood pressure. Expressing gratitude to your partner has also been shown in a study to improve communication and good feelings between you.

So every time you focus on gratitude, you are helping to combat the blues, anxiety and insomnia – and improve your relationships!

Sounds too simple to be true? Why not try it and see for yourself?


One way that is very simple and effective is to keep a journal by your bedside and every evening or morning depending on your preference, write down 3 things that you’re grateful for. It can be something as fundamental as sunshine. It can be a specific person in your life. A food you love, or a book that has inspired you. Really, anything at all. After you’ve written your three things, spend a few minutes contemplating each one, and allowing the feelings around that to arise and just be with that. Keep this journal for 10 days. If you run out of things to write down, you can always repeat some. The point is the practice itself, not the details.

Personally, I have found a gratitude practice to be a sure-fire way to shift my mood. Within only a few minutes, I experience more spaciousness and more heart-centred awareness. And interestingly, while going through some grieving for lost loved ones, a gratitude practice around my relationship with them has allowed me to replace the sadness and loss with a sense of abundance and appreciation for having had that person in my life and sharing those moments together.

The science behind a daily gratitude practice

A social-cognitive model of trait and state levels of gratitude

Counting blessings versus burdens: an experimental investigation of gratitude and subjective well-being in daily life

Examining pathways between Gratitude and Self-Rated Physical Health Across Adulthood http

A pilot randomized study of a gratitude journaling intervention on HRV and inflammatory biomarkers in Stage B heart failure patients

Recruiting the Vagus Nerve – Take a step back

This is the second in the series Recruiting the Vagus Nerve: the best friend you didn’t know you had.

Self-distancing is a powerful intervention – some people call them hacks or manoeuvres – to recruit the Vagus Nerve, that wonderful friendly nerve that controls the relaxation response of our Autonomic Nervous System. This is the tend and befriend ground or circuit of safety and connection. When we activate the vagal pathways of the Parasympathetic System, we reduce stress, anxiety and anger, as well as reducing lethargy, low motivation, and inflammation. We improve immune response, breathing, cardiac health, digestion, and lots more. The activity of the Vagus Nerve is measured as vagal tone, so the better we get at recruiting the Vagus Nerve the more we improve what our ‘vagal tone’. You can think of it as a singer toning the voice.

These interventions that target the Vagus Nerve also do something quite remarkable and unexpected – they reduce egocentric bias, that is, the tendency to over-emphasize our own personal view and experience at the expense of a broader perspective. Vagus Nerve activity reduces our tendency to over-analyze and ruminate on our emotions and reactions, hopes and fears. The Vagus Nerve helps us to be less self-conscious, which is always a liberating trend.

A number of scientific research studies have shown that techniques that involve a practice called self-distancing actually reduce this egocentric bias and improve vagal tone – our ability to self-regulate through recruiting the Vagus Nerve.

What is ‘self-distancing’? Self-distancing is developing an observer part of our consciousness. It’s getting out of our story – of predictions or fantasies about the future, if I do this then this might happen. Equally, it releases us from raking over the past which often keeps us trapped in negative thought-loops or obsessive nostalgia. Self-distancing is the opposite of self-immersion. Self-immersion always keeps us from experiencing the present moment because it involves thinking about the self instead of being the self.

According to research, when people adopt a self-distanced perspective while discussing a past difficult event or imagining a difficult future event, they make better sense of their reactions, experience less emotional distress, and display fewer physiological signs of stress, which is reflected in healthier cardiovascular activity. They also experience reduced reactivity when remembering the same problematic event weeks or months later, and they are less vulnerable to recurring thoughts (or rumination).

You can do this consciously, but this tendency can also begin to emerge as a side-effect of mindfulness and yoga techniques which train us to practice observing the body.


In one study, participants were put into one of three groups. One group performed a traditional “expressive writing” task, with instructions to wear their heart on their sleeve and write freely about their “strongest and deepest emotions.” Another group was told to engage in “narrative expressive writing”, in which they created a “coherent and organized narrative” of their marital separation with a storyline arc with a beginning, middle, and end. The third group given an emotionally neutral writing task. Participants assigned to the “narrative expressive writing” group showed the greatest reduction in cardiovascular markers for stress as well as an increase in heart rate variability (HRV). They found that people who had the best results used the question what instead of why did because why questions encourage a lot of fantasizing.

  1. TAKE THE PERSPECTIVE OF AN OBSERVER: It’s hard to stop this mental chatter altogether, so a technique that people have found useful is to imagine a stressful future or past event like a fly on the wall. This is a step towards developing what is called ‘witness consciousness’ in yogic traditions or ‘observer consciousness’. A number of studies have shown that people feel less anxious when they imagine a future stressful event – like public speaking or an upcoming interview – as an outside observer.
  2. USE THE THIRD PERSON WHEN SELF-REFERENCING: Saying your name out loud, or even in your head, when self-referencing can have the effect of encouraging a less emotional response to events. If you’re have a tough day getting motivated, you can talk yourself through the steps you need to take – like getting in the shower, making breakfast, and so on as if you are your own coach. You can even give yourself encouragement, like “Don’t worry, you can do this.” Positive self-talk in the third person can help to transform negative thoughtform loops by replacing self-criticism with self-care. In other words, we talk to ourselves the way we would talk to a friend.
  3. NARRATIVE EXPRESSIVE JOURNALING Research shows that just 20 minutes of “narrative expressive writing” over a three day period can trigger a physiological chain reaction that was found to improve Heart Rate Variability (HRV), which is the measurement of variations within beat-to-beat intervals that indicates cardiovascular health and is how vagal tone is measured.

Self-distancing helps us to maintain that BIG PICTURE – viewing our prospects from a third-person perspective helps us to notice things that we might easily miss when we’re all tangled up with it. We miss the wood for the trees, as it were. Self-distancing helps us to be MORE OBJECTIVE which in turn, helps us to take things less personally. And perhaps the greatest gift of self-distancing is the effect of SELF-FRIENDING. Developing this observer self brings in a kinder and less judgmental point of view. It is often easier to have a calm and wise perspective on a friend’s problems but less easy to have that same perspective towards our own.

With the gentle art of self-distancing, we can finally be that friend to ourselves that we try to be for others.

Featured photo by: Angela Hogg

1. The art of self-distancing https://www.psychologytoday.com/us/articles/201901/the-art-self-distancing

2. Regarding stressful events as an observer https://psycnet.apa.org/doiLanding?doi=10.1037%2Fa0019205

3. Third person self-referencing. https://www.psychologytoday.com/au/blog/the-athletes-way/201705/self-talk-using-third-person-pronouns-hacks-your-vagus-nerve

4. Narrative expressive journaling as a tool for self-distancing https://www.psychologytoday.com/intl/blog/the-athletes-way/201705/narrative-expressive-journaling-could-help-your-vagus-nerve

Recruiting the Vagus Nerve: the best friend you didn’t know you had

The Vagus nerve is a master nerve that controls various functions of the heart, lungs, stomach and intestines. Without it we would be in constant fight-or-flight stress mode and we would quite simply keel over and die – probably from a heart attack.

My interest in this work is largely informed by my own past experiences with depression and anxiety forced me to go ever deeper and to seek underlying causes for my condition. When I discovered the work of scientist Dr. Stephen Porges and read about his Polyvagal Theory a thousand lights went off in my head.

In this journey, I have discovered some fundamental practices that can dramatically change how we experience ourselves in the world. These practices bring together eastern wisdom traditions with modern science in very exciting ways that link together physical, mental, emotional and spiritual performance; cardiologists, therapists especially trauma therapists, sports coaches, educators, and yoga teachers, are just some of the professions that are benefiting enormously from these discoveries.

But this information is relevant to all of us. Because what the science of the Vagus Nerve is teaching us that we all have the power to engage with our fundamental states or grounds of being. We can find a greater sense of connection with ourselves and with others, to experience more peace, acceptance, courage, compassion, humour, creativity and playfulness. We will learn why it is important to trust our gut instinct and how to reconnect with that again – and why quality social interaction is so essential and part of what makes us human. We can become more skilled navigators of our social and emotional worlds and understand how our ideas about ourselves sometimes impede our full experience of ourselves.

Understanding the Vagus Nerve will give us insight into what fundamental forces are really driving us as human beings – how simple, powerful, and beautiful they are – and how to work WITH these forces rather than against them.

Leonardo Da Vinci was drawing the Vagus Nerve 500 years ago, but in the past 5 years the subject has exploded with dozens of books on the subject. In this Youtube video I introduce the series with a basic overview of the Vagus Nerve (think learning your way around a car and possibly doing an oil change but not becoming a full mechanic) and why I call it the best friend you never knew you had.

So what is the Vagus Nerve? The Vagus Nerve is the longest and most complex nerve in the body. Most importantly it is the main driver of our parasympathetic nervous system, what is generally called the ‘rest and digest’ mode. But it is much more than this. The Vagus Nerve is actually 2 nerves, the left and the right, but it’s referred to as a singularity. The word ‘vagus’ comes from the Latin for wanderer because this nerve wanders around the body. It’s where we get the word ‘vagabond’ and ‘vagrant’. It looks a bit like a very elongated jellyfish and it goes from the brain down either side of the neck with branches that go to the outer ear, into the muscles of the face, the throat and the larynx, and down into the heart, the lungs and the digestive organs. Understanding where the Vagus Nerve wanders in the body is key to understanding why the interventions that you’ll learn in this series work to foreground this nerve.

What does it mean to recruit the Vagus Nerve?

80% of the nerve fibres which comprise the Vagus Nerve are afferent – meaning that they TAKE information FROM the body TO the BRAIN. This is key to tuning in to this alternative approach to wellbeing that we can call BOTTOM UP, as opposed to TOP DOWN. To RECRUIT the Vagus Nerve means optimizing conditions for this nerve to signal to the higher brain centres that we are safe, that we are not under threat. And when we feel safe, all kinds of wonderful things begin to happen. we can express the parts of ourselves that we have kept hidden, perhaps because we felt too vulnerable to express them: compassion, creativity, courage and curiosity, to name a few. Are you beginning to see how important nervous system literacy can be to our mental and physical wellbeing?

How do we recruit the Vagus Nerve?

This is what I’m going to get into in this series. RECRUITING THE VAGUS NERVE – THE BEST FRIEND YOU DIDN’T KNOW YOU HAD. We’re going to explore together dozens of simple interventions that you can do at home, that don’t require expensive equipment, most of them don’t require anything at all other than a present body and an open mind. I will do my best to post one intervention a week. I’m excited to be on this journey with you. As always, respect yourself, explore yourself.

LOCKDOWN YOGA: Vagus nerve hack for neck tension, anxiety and more

From the 21 day lockdown in Varanasi, India. This fast, effective (and very cool) biohack begins with a demonstration of how movement of our eyes muscles connects to the suboccipital muscles at the back of the neck where the skull meets the spine. Yes, you really DO have eyes in the back of your head! Decompression of these muscles reduces tension in the neck, helps alleviate headaches, anxiety, sleep disorders and depression, and has been found to stimulate the Vagus nerve, a key factor in regulating the autonomic nervous system for overall well being. This is followed by the BASIC EXERCISE developed by Dr. Stanley Rosenberg that you can read about in his book, Accessing the Healing Power of the Vagus Nerve.

The Vagus Nerve, Yoga and the Heart

With all the focus on aerobic exercise, you could be forgiven for thinking that what your heart wants is for you to constantly running, swimming or cycling. But a number of Vagus nerve anatomy, illustrationmedical studies are showing that practicing yoga can significantly contributes to cardiovascular health. These days, doctors and other health practitioners are increasingly recognizing the benefits of yoga for the healthy functioning of the heart. More research, particularly in the past five years, is revealing how regular yoga practice can help to manage the levels of cortisol and adrenaline – the fight or flight/stress hormones – that stimulate the sympathetic nervous system and put pressure on the heart by narrowing the arteries and raising blood pressure.
This calming effect on the body and mind is due in large part to the activity of the Vagus Nerve, that has been dubbed the “air traffic controller” of our nervous system. The Vagus is our largest cranial nerve, connecting the brain to the rest of the body via the facial muscles, heart, lungs, digestive tract, kidneys and reproductive organs. The Vagus Nerve plays a key role in the function of the parasympathetic nervous system (our ‘all-safe’ response) and helps to regulate many bodily functions including breathing, digestion as well as how we receive and interpret information from our environment, in particular our social environment.

What is fascinating cardiologists is the connection between the Vagus Nerve and the heart. They have discovered that the Vagus Nerve regulates heart rate through electrical signals and the release of the neurotransmitter acetylcholine. It is this neurotransmitter that tells our lungs to breathe. And here lies a key. If our body is getting flooded with stress signals what can we do? It turns out that we can indirectly stimulate the Vagus Nerve (and thus develop a more finely tuned response to danger and safety) by working with the areas and functions that it controls; throat, lungs, heart and abdominal organs, but especially by working with our breath.

Pranayama, the kind of slow, rhythmic abdominal breathing that we learn to do in yoga has been shown to stimulate the Vagus Nerve and improve what is called ‘vagal tone’—that is, the body’s ability to accurately interpret signals of danger and safety and to better cope with stress. This practice, embedded for centuries within ancient wisdom traditions, is fast coming to be seen an advanced biohack technique and a promising part of the future of medicine.

For information email: lavieenyoga@gmail.com

Respect yourself, explore yourself.