I’m continuously awed by the brilliance of the human body, its almost limitless capabilities, its strength in sustaining us in the most extreme circumstances and the way every cell, and every system, work in harmony.
Key to much of the harmonious interaction of our vital organs is the vagus nerve, and if we want to age well, we need to look after it. This nerve, or more accurately, bunch of nerves, connects most of the major organs of the body to the brain. It wanders through us, vagrant-like (hence the name), starting its journey at the lowest part of the brain, passing through the vocal chords, lungs, heart, spleen and liver before wrapping around the digestive systems, and ending up in the colon. It’s a brain-body information superhighway, pulsing messages back and forth, giving the brain a moment-by-moment account of what’s happening in our bodies.
Most importantly, the vagus nerve co-ordinates interaction between breathing and heart rate, helping us to calm down after we’ve been stressed. In a tense situation, our breath becomes short and shallow, our heart rate speeds up in preparation for ‘fight or flight’ and our sympathetic nervous system floods the body with adrenaline and cortisol. When the threat has gone, the parasympathetic nervous system, controlled by the vagus, slows the heart and breath allowing us to relax again.
Problems occur when we are chronically stressed and our ‘fight or flight’ response gets stuck in the ‘on’ position. This prevents the vagus from initiating the relaxation response, leading to poor Heart Rate Variability (HRV), the difference between a faster heart rate on the inhale and a slower heart rate on the exhale. When the vagus is able to work well, there’s a clear difference between the two, but when we’re chronically stressed its work is impeded. The effects of this go far beyond the physical – remember I said that the vagus is the brain-body superhighway? Low HRV has been linked to lack of resilience, loneliness and increased dependence on alcohol.
This two-way brain-body connection goes further: chronic stress raises levels of pro-inflammatory cytokines which can lead to depression. The root cause? Inflammatory-inducing proteins entering brain via the vagus nerve. Inflammation is at the heart of so many chronic conditions of ageing, including rheumatoid arthritis, Alzheimer’s and heart disease. If we want to reduce our risk of these age-related conditions, toning the vagus nerve (yes, like a muscle) is the single best thing we can do. Of course, like so much else in the body, it’s activity declines as we get older.
Neuroscientists refer to the vagus as the love nerve, or caretaking nerve, of the body. It’s connected to receptors of oxytocin, the hormone released when we fall in love, create a happy marriage, bond with our children or enjoy time with friends. Having fun and being positive stimulates the vagus and it, in turn, rewards us with increased health and more happiness.
Conversely, the vagus is also activated by images of suffering – it’s switched on by empathy and compassion. Sad stories, books and films all promote empathy and stimulate the vagus. People with a strong vagus tend to be more helpful and compassionate.
Try these simple tips
We can tone our vagus nerve with deep, rhythmic breathing (try breathing in for five counts, out for five counts), singing, laughing, meditation, cold showers and humming. Yes, humming. The vagus nerve is connected to the vocal chords so humming a tune, or a low ‘om’ stimulate it. I hum in my (cold) shower!
The vagus responds to better to HIIT exercise, than to endurance training which can over stimulate it. Taking care of our gut health keeps the vagus toned too. There are lots of good gut recipes on the blog. Try:
Photo by Robert Owen-Wahl CharterForCompassion.org