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The gut-brain connection

The gut-brain connection

Nausea and vomiting are common complaints among migraine patients. Many are confused by this strange symptom. What in the world does digestion have to do with a neurological disorder of the brain? How are the brain and digestive system connected?

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Scientists who study this connection refer to the digestive system as the “gut brain”, “second brain”, or more formally as the enteric nervous system (ENS). The vagus nerve connects the brain stem directly to the ENS, enabling direct communication between the two. No other organ system has such a direct pipeline to the brain. Over 90% of the signals traveling along the vagus nerve are sent from the ENS to the brain. Additionally, the ENS is capable of regulating digestion independently of the brain. This was demonstrated by a study in which researchers severed the vagus nerve of rats only to find that their digestive tracts were still functioning 100%. No other organ system can operate independently of the central nervous system.

The ENS contains over 500 million neurons and 40 neurotransmitters. It produces 50% of the body’s dopamine and over 95% of serotonin. This explains why psychotropic medications often trigger digestive upset as a side effect. These neurotransmitters have also been linked to migraines. Disrupt these neurotransmitters and you will experience digestive, emotional, and physical problems.

The role of stress in pain perception

Have you ever experienced “butterflies” in your gut when nervous? This feeling is a result of blood flowing away from the ENS into your muscles as a result of activating the brain’s Fight or Flight response. Our bodies are very inefficient when it comes to dealing with modern stress.  The Fight or Flight system fires whether the danger is real or perceived. There is no distinction between mortal danger and emotional stress. The body responds exactly the same way.  Heart rate increase, blood flows to the muscles, breathing is shallow, and adrenaline floods the body. As a result we may feel nauseous, dizzy, and think we are having a heart attack. We can experience tunnel vision, difficulty swallowing, and shaky hands. In a life-threatening situation, these changes prepare us to run from danger or stand and fight.  When we experience psychological stress, the changes that normally prepare us to take action are left unused. It can take 30 minutes or longer for our brains to realize the threat was a “false alarm” and even longer for our bodies to return to a non-threatened state. Meanwhile we feel pretty miserable. These dramatic changes could be why so many of us identify stress as a primary migraine trigger.

Increased risk of disease

This alarm system also releases inflammatory cytokines that send the immune system into “high alert”. When our immune system is activated, white blood cells increase, and inflammation occurs throughout the body.  Over time, chronic stress keeps this inflammation going all the time. Unchecked inflammation has been linked to the development of depression, anxiety, high blood pressure, atherosclerosis, autoimmune diseases such as MS or ulcerative colitis, and even cancer. How many times have you gotten a migraine as a result of getting sick? It is possible that increased inflammation resulting from stress triggered both.

The role of diet

Some of these stress responses affect pain perception, making our experience of migraine much worse.  In fact, patients with GI problems (IBS, UC, ulcers, etc.) perceive pain more than those who do not. This is theorized to be caused by the brain’s inability to accurately regulate pain signals that come from the ENS. Essentially, stress makes our pain feel worse. But the news is not all bad. Some types of beneficial bacterial (bifidobacterium and lactobaccilus) help turn off the stress response by shutting down production of cortisol and adrenaline. The typical American diet of highly refined foods and germ-free environment reduces the population of these beneficial gut bacteria. However, a diet rich in wholesome fruits and vegetable can actually support the growth of beneficial bacteria and reduce our pain.

Chronic stress also causes the permanent elevation of hormones that increase your craving for high carb, high fat foods. Giving in to these cravings results in decreased anxiety, improved mood, and stimulates the release of dopamine (the reward neurotransmitter). This is just one more way that stress contributes to the development of obesity. These cravings are similar to the cravings we get during the prodrome phase of migraine. Sometimes we actually crave the very foods that trigger migraine.

How therapy helps

There are some physical symptoms that have been shown to improve with psychotherapy. This isn’t because the problem is “all in your head”. It is because both the brain and the digestive system work together to utilize the body’s Fight or Flight response to perceived threat. There are no medical treatments to correct the “false alarms” that happen as a result of psychological stress. So, when medical treatment alone fails, doctors often recommend psychotherapy to patients. These recommendations are often made with the best of intentions, just not delivered or received well.  Doctors are not therapists, so they often lack the communication skills to explain this complex system effectively enough to patients.

So many patients leave their doctor’s office frustrated, hurt, and feeling abandoned. They rarely follow up on the doctor’s recommendation. When they do, they don’t know enough to ask for a therapist who specializes in chronic health problems. The entire system fails and the patients suffer.

Chronic stress messes up the feedback between ENS and the brain, triggering all kind of physiological and emotional disorders such as anxiety, depression, IBS, headaches, high blood pressure, and much more.  Because the brain and body are so interconnected, you can learn to counteract the negative effects of stress by changing your behaviors and thinking patterns. You can literally change the messages being sent between gut and brain by what you tell yourself.

To begin making this kind of change, you will need to look for a therapist who specializes in behavioral pain management, chronic pain, or health psychology. Expect therapy to focus on cognitive and behavioral strategies to counteract the effects of stress. This won’t be the stereotypical “lay on the couch and talk about my childhood” therapy. Very few counselors actually do that anymore.1-5

This article represents the opinions, thoughts, and experiences of the author; none of this content has been paid for by any advertiser. The Migraine.com team does not recommend or endorse any products or treatments discussed herein. Learn more about how we maintain editorial integrity here.

  1. http://www.scientificamerican.com/article/gut-second-brain/
  2. http://neurosciencestuff.tumblr.com/post/38271759345/gut-instincts-the-secrets-of-your-second-brain
  3. http://www.health.harvard.edu/healthbeat/the-gut-brain-connection
  4. http://www.npr.org/blogs/health/2013/11/18/244526773/gut-bacteria-might-guide-the-workings-of-our-minds
  5. http://www.psychologytoday.com/blog/evolutionary-psychiatry/201404/the-gut-brain-connection-mental-illness-and-disease

Comments

  • Maria Walheer
    3 years ago

    Very informative article.

    As a trauma survivor (military sexual assault), I believe it is important to discuss Flight, Fight or FREEZE responses.

    We tend to forget that sometimes the body just freezes as responses to threats.

    I would love to share more information to anyone who does not understand the freeze response.

  • Luna
    4 years ago

    TAMMY—
    “The Gut Brain Connection” is a comprehensive guide to how”

    Who is this by and where is it found. Googled but didn’t find it.

  • Teresa
    4 years ago

    And also, this article is titled “The gut-brain connection”

  • Teresa
    4 years ago

    Click on the link that says
    “View references”
    That will show you where she gets her information for this and other articles if you ever have any questions.

  • Ellen.S
    5 years ago

    HI ALL,
    I HAVE BEEN SUFFERING FROM MIGRAINES FOR 27 YEARS. AS YOU CAN IMAGINE, I HAVE TRIED EVERY MEDICATION AND SO CALLED PREVENTITIVE THERE IS. I HAVE ALSO TIRED “NATURAL/ALTERNATIVES”. SADLY WITHOUT ANY CHANGE.

    I STARTED GETTING (M’S) TWICE A WEEK, ON AND OFF FOR 10 YEARS. 2 TIMES A WEEK IS JUST TOO MUCH. WHICH MEANS I HAVE LOST 3-6 DAYS OUT OF THE WEEK. MY (M’S) ARE SEVERE AND USDED TO BE WITHOUT AURA. EVERYTHING IS CHANGING. MY AMERGE THAT I HAVE TAKEN FOR SO LONG HAS STOPPED WORKING.I HAVE ORDERED THE ‘CEFALY’ DEVICE TO HELP, I HOPE. BUT FOR NOW I AM WITHOUT ANYTHING.

    27 YEARS AGO I WAS ALSO DIAGNOSED WITH HASHIMOTTO’S AND FIBROMYALGIA. BASED ON THAT NEWS I STOPPED EATING ANY PROCESSED FOODS AND WAS ONE OF THE FIRST TO COOK/BAKE EVERYTHIG FROM SCRATCH WITH ALL NATURAL/ORGANIC WHOLE GRAIN INGREDIENTS. NOW THAT I CAN’T GO BACK TO BAD HABBITS, I WISH I COULD SAY THAT ALL THAT WORK HAS PAID OFF. I AM NOT DISCOURAGING YOU TO IMPROVE YOUR LIFESTYLE. ONCE YOU DO, YOU FEEL AS IF YOU ARE DOING YOUR PART.

    WHAT I HAVE GIVEN UP ON IS, DOCTORS. THEY JUST DON’T GET IT. WHEN ANYONE SEES YOU (WITHOUT M) THEY THINK THAT YOU ARE FINE, EVEN WHEN IN WHAT I CALL, MIGRAINE MODE. THEY HAVE NOT SEEN ME WHEN IN ER WAITING ROOMS OR URGENT CARE WHEN ALL MEDS FAIL.

    I AM NOW DEALING WITH REALLY BAD GERD, GALL BLADDER AND KIDNEY DISEASE. I THINK FROM THE TRIPTANS OVER THE YEARS.
    MY NEXT STEP IS TO AGAIN TRY ELIMINATION DIET WITH ROTATION DIET.

    IN 2012 I WENT ON THE GAPS DIET AND ELIMINATED GLUTEN, DAIRY, SUGAR AND MUCH MORE. I WAS ON THAT FOR 9 MONTHS AND GAVE UP BECAUSE THERE WAS NO CHANGE. I ADMIT I STARTED FOR THE DIGESTIVE PROBLEMS, BUT HOPED AND PRAYED IT WOULD SLOW DOWN THE (M’S)

    I HAVE BEEN MEDITATING FOR 27 YEARS AS WELL. FOR ME STRESS IS NOT A DIRECT FACTOR, EXCEPT FOR THE FIBRO. AS A MATTER OF FACT WHEN MY ADRENALINE GETS GOING, MY (M’S) WAIT A DAY OR TWO TO DEVELOPE. BUYING ME SOME PRESCIOUS TIME.

    I AM CERTAIN THAT THERE IS A GUT/BRAIN CONNECTION, BUT I DO NOT KNOW ANY MORE THEN THE MEDICAL EXPERTS.

    THANKS FOR LISTENING TO ME!

  • Luna
    5 years ago

    “Disrupt these neurotransmitters and you will experience digestive, emotional, and physical problems.”
    The research also says that a sick digestive system will cause emotional and physical problems. So a healthy gut is just as important as healthy thinking.

  • Jules2dl
    5 years ago

    Hi Tammy;
    I’ve recently been wondering if some of the issues I have with my gut (some life long and some new) could be related to my migraines. Is there a book you could recommend which delves further into this subject, as well as one which explains the cognitive and behavioral strategies to counteract stress which you refer to in your post?
    At this point, I’m mostly home bound due to my migraines, and also haven’t the funds to see a therapist, so a good book would be helpful.
    Thanks,
    Julie

  • Tammy Rome author
    5 years ago

    The best book for cognitive strategies is “Smart, but Scattered”. I based the “Migraine Brain” series on the tips in that book.

    “The Gut Brain Connection” is a comprehensive guide to how diet affects our mood, pain perception, and cognitive functioning.

    You might also consider online therapy. It’s generally much less expensive and you don’t have to leave home. A good place to check out is http://www.betterhelp.com.

    Hope these tips help.

  • Brenda
    5 years ago

    This couldn’t have come at a better time! I have chronic nerve pain and migraines. In the past 2 years, I’ve developed a problem with my stomach that the doctors can’t really figure out. They know I have GERD & a hiatal hernia but tell me that they are not causing my symptoms – severe nausea & debilitating cold sweats. I am certain that the vagus nerve is being triggered and I have noticed that my migraines increase when I have these episodes (4 in the last 2 years). I would love to find a therapist that specializes in pain management, but have no idea how to go about it. Any suggestions?

  • Teresa
    4 years ago

    Ellen,
    You might find it works better for you to raise your bed instead of your head. (Ha, I’m a poet.) If you put 2×4 blocks under the feet of the head of your bed, you will not slide off, but it will still help with the GERD. I am a fellow sufferer.

  • Ellen.S
    5 years ago

    ME TOO PAST 2 YEARS. I ALSO HAVE HIATAL HERNIA, SEVERE GERD. NOT ON ANY MEDS FOR THAT BECAUSE OF ALLERGIES TO ALMOST EVERYTHING.BESIDES THAT IS A BANDADE NOT A CURE FOR GUT/BRAIN PROBLEMS.

    AT LEAST I REMOVED THE RAISED PILLOW/WEDGE TO HELP KEEP ACID OUT OF MY THROAT AT NIGHT. I WAS GETTING NECK AND BACK PROBLEMS FROM RAISING MY HEAD, NOT TO MENTION SLIDING DOWN AND ALMOST OFF THE BED! HA.

  • Tammy Rome author
    5 years ago

    You might ask your doctor for a referral. You can also check out a couple of referral websites. GoodTherapy.com and Theravive.com are my favorites. Theravive is especially good because they list only therapists who are comfortable dealing with values, spirituality, etc. When I was still practicing, I was listed on both. GoodTherapy also has a ton of really good articles.

  • Kerrie Smyres moderator
    5 years ago

    Really helpful information, Tammy. Thanks!

  • body
    5 years ago

    Nice article, Tammy. Great to see a post on migraine and the “gut-brain” connection. 🙂

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