The vagus nerve is the direct line of communication between the gut and the brain. Scientists are researching how this pathway may play a significant role in obesity and may be a key tool in promoting weight loss. In this article, we explore the benefits of vagus nerve stimulation (VNS), the role the vagus nerve could play in obesity, and tips on stimulating your vagus nerve to help calm your nervous system.
The vagus nerve is a crucial communication pathway between the gut and the brain.
Sensors in the vagus nerve tell the brain when we are full and hungry by triggering the release of hormone cholecystokinin, which aids in satiety.
Vagus nerve stimulation has not been formally approved for weight loss. However, scientists are currently studying if it can be a tool to manage obesity.
You can stimulate your vagus nerve through deep breathing, massage, exercise, and diet.
What is the vagus nerve?
The vagus nerve is the longest cranial nerve in the body. It can send mechanical and chemical signals from the brain stem to many major organs in our body.
The vagus nerve is the main component of the parasympathetic nervous system. The various parasympathetic nervous system functions predominate during the rest and digest state - when our body is relaxed and the nervous system can focus on conserving energy and regulating involuntary body processes.
The parasympathetic nervous system oversees many functions, including:
- Immune system response
- Lowering heart rate
- Controlling rate of breathing
- Mood control
While research is limited, studies have reported that vagal nerve stimulation (VNS) may help trigger or hinder appetite signals from the brain to the gastrointestinal system, helping to curb the desire for high-fat and sugary foods.
What is vagus nerve stimulation?
Vagus nerve stimulation is a novel therapeutic method, approved by the FDA, mediated by an implantable medical device, currently used to treat epilepsy, severe depression, and stroke rehabilitation.
There is also an FDA-approved hand-held VNS device that does not require surgery and is used to treat cluster headaches and migraines. Several non-invasive wearable VNS devices can be purchased online to help with improving vagal tone, which is a great way to test out if VNS is a good tool for you.
The VNS sends mild electrical impulses from the left vagus nerve to the brain, providing support for brain cell signaling.
How does VNS help with obesity?
Although VNS is not an approved treatment for obesity, the vagus nerve plays a vital role in digestion and gut health. Interestingly, a small case study focused on using VNS to treat severe depression found that four out of six patients additionally lost weight during the treatment, sparking interest in using VNS could help manage weight.
The gut-brain feedback loop (mediated via the vagus nerve) plays a significant role in the feeling of satiety. Frequent consumption of calorie-rich and sugary foods may reduce the sensitivity of vagal neurons to peripheral signals, therefore, the body does not know when to release cholecystokinin, preventing the feeling of satiety. VNS may serve as a potential solution proposed to help vagal neurons react and send further signals to release satiety hormone, suggestively leading to decreased food consumption.
If you have low vagal tone (stimulation) in the gut area, it can lead to various physical symptoms, including:
- Weight gain
- Joint and muscle pain
VNS tips on improving health
While implantable VNS medical devices have not been approved for weight loss, you can stimulate your vagus nerve in several ways to help improve digestion, mental health, and overall wellness.
Mindfulness, yoga, and deep breathing are great ways to stimulate your vagus nerve to promote calm and relaxation.
Diaphragmatic breathing is a form of deep breathing when the diaphragm contracts on the inhale and relaxes on the exhale. This mind-body exercise signals your brain that it is time to relax and calm down.
Senobi breathing has also been suggested to help activate the parasympathetic nervous system. It is a form of breathing adapted by the Japanese that involves stretching your arms over your head and inhaling and exhaling slowly. Some limited studies have found that Senobi breathing may lead to some fat loss in women with obesity.
Cold shower or plunge
Exposing your body to cold temperatures in the shower, splashing cold water on your face, or submerging yourself in a cold plunge for about three minutes, are great ways to trigger your vagus nerve.
Studies have shown that cold water may help speed your metabolism, stimulate fat-burning and potentially help manage weight.
Alter your diet
Eliminating highly processed and sugary foods from your diet may help improve gut-brain axis communication and promote weight loss.
Foods high in omega-3 fatty acids (fish, nuts, seeds) can help reduce inflammation. High-fiber foods work as prebiotics that are fermented by the gut bacteria, producing short-chain fatty acids, that may help stimulate hormones responsible for satiety and energy intake regulation.
High-fiber foods include:
- Citrus fruits
Moving your body daily is critical to weight loss and well-being. Mild to moderate exercise activates the vagus nerve and increases dopamine.
Aerobic exercises and activities that trigger the vagus nerve and promote weight loss include:
The vagus nerve can be stimulated by massaging specific touch points on your body.
are becoming a popular tool to reduce stress and help regulate feelings of anxiety. One study found that 60 minutes of foot reflexology can lower your blood pressure and heart rate and improve vagal tone.
A vagal massage may also help minimize migraine symptoms, improve digestion, and reduce inflammation.
Effective places to massage the vagus nerve include:
Intermittent fasting gives your digestive system a break and can help promote weight loss and improve vagal tone.
While fasting times may differ from person to person, it is common to follow a 14–18 hour fast, but it is important talk with your doctor before fasting, as it is not recommended for everyone.
While VNS has not been approved as a formal treatment for obesity, researchers continue studying the effects of the gut-brain connection with digestion, satiety, and weight loss. Many smaller studies have shown that improving vagal tone can improve gut health and combat feelings of stress and anxiety.
In the meantime, stimulating your vagus nerve through deep breathing, regular exercise, and massage is a great way to improve physical and mental health.
- Frontiers in Psychology. Vagus Nerve as Modulator of the Brain–Gut Axis in Psychiatric and Inflammatory Disorders.
- Journal of Natural Science, Biology, and Medicine. Vagal nerve stimulator: Evolving trends.
- International Journal of Obesity. Weight loss during chronic, cervical vagus nerve stimulation in depressed patients with obesity.
- Food Research International. Effects of ultra-processed foods on the microbiota-gut-brain axis: The bread-and-butter issue.
- Biomedical Research. The "Senobi" breathing exercise is recommended as first line treatment for obesity.