Treating your Gut to Treat your Brain: The Link Between Gut Health and Your Brain

Have you been feeling low and unmotivated and are not sure of the reason why? Or perhaps you have been feeling anxious when you normally think of yourself as a pretty relaxed person?

It may actually be your gut that needs addressing. These two scenarios are examples of the connection between our brain and our gut known as the Gut-Brain axis. This axis refers to a two-way communication pathway going on between our digestive system and our brain and whatever is going on in one will affect the other.

In the last couple of decades, research in this area has seriously exploded in this area with significant correlations shown between levels of stress and mood disorders and gastrointestinal related disorders. In fact, 40-60% of patients with functional gastrointestinal disorders experience psychiatric symptoms and up to 50% of psychiatric patients are diagnosed with irritable bowel syndrome.

 

What exactly is it?

 This gut-brain axis, a two-way communication pathway. uses traffic lights, or signalling hormones, and all sorts of other fancy messengers to manage what we do and how we feel on a day-to-day basis.

The gut microbiome is central to all of this. In case you’re wondering, the microbiome is the environment of microorganisms such as bacteria, viruses and fungi that inhabit our digestive tract. The microorganisms in our gut directly impact the messages being sent to our brain. So just as your mood influences and cause changes to your gut bacteria, your gut bacteria also influence your mood.

 

How our gut affects our brain

 The function of our brains can be expressed in most simple terms as communication. The neurons communicate with one another, and with our muscles and organs, to execute bodily function and maintain balance. Neurotransmitters are the chemicals that carry out this communication as they travel between neurons. They are like messengers and too much or too little of any of one neurotransmitter can change the way you think, feel and behave.

Whilst we often think of neurotransmitters being produced in the brain, a large majority of these little guys are actually produced in the gut. In fact, more neurotransmitters are produced in the gut than in the brain:

 

  1. Serotonin

Serotonin is our “happy hormone” and is well known for its role in regulating mood, appetite and sleep. Serotonin levels can play a part in mood disorders such as depression, obsessive-compulsive disorder and anger management problems.

Experts once believed that serotonin was produced exclusively by the brain but we now know that up to 90% of the serotonin we rely on everyday is actually produced in our gut. Certain types of microbes in the gut can directly stimulate the production and release of serotonin in the cells lining the colon. If your gut isn’t functioning properly, the cells and bacteria are not going to be able to produce enough serotonin to balance your mood.

 

  1. Dopamine

Dopamine is another major neurotransmitter that plays an important role in attention, problem-solving and memory. It is also associated with reward-inducing mechanisms, in things that give us pleasure. So if you were to eat a piece of chocolate, dopamine would be released in some areas of the brain, allowing you to feel pleasure and giving you reason to keep reaching for another piece. What you may not know is that 50% of your dopamine is produced in the gastrointestinal tract.

 You also need to have healthy gut bacteria in order to produce vitamin B12 and that plays a huge role in mental health. B12 deficiencies are a root case of neurological, psychiatric and cognitive issues and have been shown to be associated with depression. It can trigger symptoms in the nervous system and red blood cells and can impact your neurotransmitter pathways. If you’re not absorbing and digesting your vitamin B12, you’re not going to have the healthy serotonin or dopamine levels either.

 

How does stress impact our gut?

So we’ve already seen how your gut affects your brain, what about the other way around? Have you ever had a nerve-wracking interview which upset your tummy for days? That’s exactly what we’re talking about.

When we are stressed or anxious, research shows that this increases harmful bacteria in our gut leading to feelings of anxiety or depression. In fact, people with depression or anxiety have actually been shown to have lower diversities of bacteria in their gut. An imbalance of bacteria can also lead to other nervous system conditions such as obesity, addiction and eating disorders. In fact, 60% of patients with IBS (which we learnt about last week) indicate that stress is the factor triggering either the first onset or the exacerbation of symptoms.

 So let’s look at how stress impacts the gut..

In response to stress (whether it’s perceived or actual), your body produces the hormone cortisol. Cortisol has many important functions in the stress response and impacts your gut function in various ways:

  • It diverts blood away from the gut to your muscles (to fight or run from your stressor);
  • It slows down the production of saliva in your mouth meaning the enzymes available to break down food is reduced (impairing digestion)
  • It decreases prostaglandins, which protect your stomach from acid so you might have a more sensitive tummy when you are stressed;
  • It slows down digestion or causes sudden diarrhoea, which might mean you aren’t absorbing nutrients as well;
  • It downregulates your immune system and
  • It can cause the stomach and oesophagus to spasm.

All of this is fine in the short-term, but in cases where stress is prolonged and food isn’t digested properly, it can really play havoc on the delicate ecosystem found in your gut.

 

Tips to managing your stress

As you can see, knowing how to better manage your stress is essential not just for your state of mind and your relationships, but also for your physical health. Here are six tips to alleviating the stress in your life:

  1. Journaling your thoughts and practicing gratitude. Regularly expressing gratitude may help reduce the negative effects of stress and improve your overall wellbeing. Write down every day 5 things you are grateful for.
  2. Take a deep breath. Shallow breathing is a signal that communicates to the body that something is wrong, that danger is present, and the body can release stress hormones accordingly. A few deep, diaphragmatic breaths a few times a day can be enormously healing as they activate the vagus nerve which slows heart rate, lowers blood pressure, and decreases inflammation.
  3. Ground yourself in nature to help decrease too much positive charge that can build up in our bodies over time leading to both physical and mental health problems
  4. Exercise regularly. Aim for at least 30 minutes of exercise per day as it reduces stress, boosts endorphins, increases blood flow and improves sleep to mention just a few benefits.
  5. Cultivate close personal relationships. The vagus nerve responds to human connectivity and physical touch to activate the parasympathetic nervous system, which increases oxytocin and decreases cortisol. Spend quality time with loved ones as much as possible.
  6. Finally, finding a life purpose makes living enjoyable. Living on purpose gives you direction, makes you feel alive and authentic and offers definite emotional, psychological and physical benefits.

 

Eating for your brain  

Diet is fundamental in determining the diversity of our gut microbiome and the metabolites, including those neurotransmitters that our gut species produce. Here are some simple ways you can alter your diet to build a healthier gut:

 

Avoid gut-destroying foods

 It’s important to not only focus on foods that build our gut flora but also avoid those which destroy it. Avoiding foods which are packed with added sugar as this feeds the bad bacteria. Highly processed foods, artificial sweeteners, red meat and alcohol all have a negative effect on our gut microbiota and leads to inflammation. A diet high in saturated fats, such as those found in fatty meat, butter and cheese can also affect both the diversity and abundance of your good bacteria.

 

Eat plenty of fibre

Of all the major nutrient groups that we eat, fibre is the one component that directly feeds our gut flora. That is why it is so important we get enough of it. Our gut bacteria digests the fibre and produces short chain fatty acids which are tied to a myriad of health benefits. By eating fibre, we are pretty much ensuring those trillions of gut bacteria are well fed so they can keep us in good health. If they aren’t getting fed properly, their ability to create specific vitamins like B12 and B9, decreases, and impacts neurotransmitter synthesis and affecting your cognitive ability and mental health. You can increase your fibre intake through foods such as:

  • Beans
  • Leeks
  • Asparagus
  • Cabbage
  • Chicory
  • Jerusalem Artichokes
  • Garlic
  • Onions
  • Chickpeas
  • Lentils
  • Red kidney beans
  • Watermelon
  • Nectarines
  • Bananas
  • Pears
  • Grapefruit
  • Dates
  • Figs
  • Cashews
  • Pistachio nuts

 

Focus on probiotic foods

In order to build a strong army of good microbes, eat plenty of foods rich in probiotics such as sauerkraut, kimchi, live yoghurt and kombucha. Probiotic supplements can also be very beneficial.

Studies have shown that probiotic therapy reduces depressive symptoms and improves the stress response as effectively as Citalopram or Diazepam, two very common antidepressant and anti-anxiety medications. In a 30-day study, healthy volunteers with no previous depressive symptoms were given either probiotics or antidepressants. Those given probiotics showed reduced cortisol levels and improved self-reported psychological effects to a similar degree as participants who received Diazepam. Some even say that in the future, we might find that these “psychobiotics” could restructure the gut microbiota to achieve society-wide control on mental illnesses!

 

Stock up on your omega-3s

A diet rich in omega-3 fatty acids decreases your risk of developing schizophrenia, depression, ADHD and other mental disorders. Having sufficient omega-3’s in your diet increases production of important neurotransmitters like dopamine and serotonin. Great sources include avocadoes, chia seeds, flaxseeds, walnuts and olive oil.

 

Wrapping up

If you have been feeling low and unmotivated and are not sure of the reason why or if you have been feeling anxious when you normally are pretty relaxed, the answer may be lying with your gut. The sooner you start incorporating some of these healthy gut-building strategies the better as not only will it help you improve your physical health, but it will also go a long way for your state of mind.

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