Wearable vibrating gadgets are being hailed on TikTok as a cure for chronic stress. The devices — bracelets, pendants, neck collars and ear pieces — perform “vagus nerve stimulation” (VNS), which, TikTokers claim, is the secret to switching your nervous system to calm. It sounds quite a lot like wellness claptrap. Is it?
The vagus is the longest cranial nerve in the body, connecting the brain with all the main organs — the heart, lungs, stomach, intestines, liver — and conveying information in both directions. Imagine it as a bit like a tree, with two nerves running down both sides of your neck, each with 100,000 fibres, branching out into almost every part of your body. It influences functions from our heart rate to our mood, sexual arousal and digestive health.
One of its biggest jobs is to help regulate our stress response. The vagus nerve is part of our autonomic nervous system, which has two parts: the sympathetic nervous system (SNS) — responsible for the heightened anxiety of “fight or flight mode” — and the parasympathetic nervous system (PNS) — associated with “rest and digest” when we’re calm. The two should be in balance, like a set of scales. But in our relentless modern lives the SNS can dominate, locking us in a stress loop, our brains not having evolved to separate the perceived threat of an irate WhatsApp message from being attacked by a lion.
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That’s where vagus nerve stimulation comes in. If our SNS is heightened, the brain reduces the number of signals going through the vagus. Once we feel more relaxed, the vagus is turned back up. “It’s thought that if we enhance its activity, then we may well be able to enhance the parasympathetic side and tilt the scales in that more relaxing direction,” says Hamish McAllister-Williams, professor of affective disorders at Newcastle University.
Surgically implanted VNS devices can help people with treatment-resistant depression. One study by Washington University School of Medicine found the devices had a significant impact on symptoms and quality of life. But what about VNS devices that offer non-invasive stimulation through the skin? These include gadgets such as the Nurosym (£599), which clips on to the ear, or the Pulsetto (from £542), which sits around the neck, both of which release gentle electric pulses. “We have much less evidence for their effectiveness,” McAllister-Williams says. The same goes for exercises such as deep breathing or humming, which are often promoted online as having the ability to stimulate the vagus nerve, but for which there is limited science.
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So what can we do? Good news for cold water swimmers: research has found that immersing your face can help to stimulate the vagus nerve. Other activities that may be beneficial — although evidence is limited — include endurance exercise such as jogging or cycling, and gentle massage.
Splashed out on an expensive vagal nerve stimulator? “If you’re using them for 30 minutes, sitting quietly, that alone is beneficial for stress,” McAllister-Williams says. “Even if the stimulator does nothing, it may be encouraging people to spend time in a more meditative state and that can do their mental wellbeing a lot of good.”
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