How The Vagus Nerve Affects Digestion
Sure, digestion issues like gas and bloating could be caused by eating the wrong foods. But it could also be because of a problem with your vagus nerve, which serves as the main communication link for the gut-brain axis.
You’re so smart that you have two brains. It’s kind of true. Everybody has an enteric nervous system (ENS), which operates independently of the central nervous system. The ENS is like the second brain of the body. Embedded in the wall of the gastrointestinal system, the ENS is almost self-governing and contains approximately 600 million neurons, which is more nervous system messengers than the spine!
In a nutshell, the ENS is the supercomputer of your gastrointestinal tract.
Linking your ENS to your brain is the longest of the 12 pairs of cranial nerves that originate in the brainstem is the vagus nerve.
Unless you frequently visit a chiropractor who has schooled you on the inner-workings of the vagus nerve, you probably never give it any thought. But if your digestion has been chronically problematic, you may want to get to know it better. So let’s do just that…
What is the vagus nerve?
As a 2018 research paper in Frontiers in Psychology explains, The vagus nerve is the main component of the parasympathetic nervous system or PNS. The PNS is the “rest and digest'' branch of the autonomic nervous system, which controls actions in the body you’re not conscious of, such as the heart beat. The PNS is the Yin energy complement to your sympathetic or “fight, flight or freeze” Yang branch of the nervous system.
The PNS controls digestion, mood and immune response, among other critical functions. The vagus nerve is in charge of the communication network between the brain and the gastrointestinal tract. Operating a continuous feedback loop between the brain and GI tract, the vagus nerve sends information about the state of the inner organs to the brain through afferent fibers, which you can think of as fiber-optic cables for a high-speed Internet connection.
Researchers are getting a better understanding of how an underfiring vagus nerve can cause gastrointestinal and psychiatric disorders. (Poor gut function is commonly linked with mood imbalances.)
Low Vagal Tone
A misfiring vagus nerve is said to have low vagal tone. Like atrophied muscle tissue, the vagus nerve can be strengthened. But instead of weights and dumbbells, the nerve is stimulated by using an implanted pulse generator and lead wire. This procedure stabilizes abnormal electrical activity in the brain, which can negatively impact the enteric nervous system and digestion.
Unfortunately, getting a vagus nerve makeover isn’t as easy as going to the gym for strength training. Up until recently, the procedure required a surgical implant and is approved by the FDA only for seizures or severe depression.
The good news is that according to the Mayo Clinic, a noninvasive device that stimulates the vagus nerve was recently approved by the FDA.
But what if you don’t have depression and just want to resolve poor digestion symptoms such as gas, bloating and constipation? Can anything be done to improve vagus nerve tone?
How To Improve the Vagus Nerve
According to the Frontiers in Psychology study, there is preliminary evidence that vagus nerve stimulation is a promising add-on treatment for inflammatory bowel disease (as well as depression and PTSD), which is great news if you suffer from Ulcerative Colitis or Crohn's Disease, the two major IBD afflictions.
So what can you do short of surgery to improve vagus nerve function? Getting chiropractic adjustments is one option. An adjustment may improve the alignment and movement of the spine, which in turn could improve vagus nerve activity.
You can also test the function of your vagus nerve by doing an at-home heart rate variability (HRV) function test. The HRV test measures the intervals between each heartbeat. The higher the HRV score, the better off your vagus nerve tone (activity) usually is. The HRV test lasts 10 minutes tops and is completely non-invasive. Half the time, a chest strap measures your HRV while you’re laying down. Then, the second half of the test measures HRV while you’re standing. A value of 100 or greater is considered healthy.
A simpler way to improve vagal tone, says Frontiers in Psychology is through breathing, meditation and yoga. That’s because the vagus nerve has a high capacity to regulate your stress response. Take care of your vagus nerve and it’ll take better care of your digestion.
