I hope you enjoyed reading part one and had a few ah-ha moments throughout. My goal is that you’ve walked away now realising how important having a healthy gut is to your overall health. In this second part of the series, we’ll learn about how stress affects gut health and how to start getting your gut in tip-top shape.

If you missed part one of this important two-part series, you can catch it here.

Stress and Leaky Gut

Stress and mental health issues are associated with inflammatory bowel conditions and leaky gut. I’ll explain how this works. 

A healthy gut makes neurotransmitters (chemicals that affect the brain and nerves) and is able to directly communicate with the brain via the vagus (or wandering) nerve. It does this by sending signals to the brain. A healthy brain is also able to send appropriate messages back to the gut, but this process is more difficult in an unhealthy brain.

Stress hormones can result in reduced levels of mood-boosting neurotransmitters in the brain and increase the risk of developing gut disorders, or flare-ups of existing gut disorders.

Stress hormones increase your risk of gut disorders or flare-ups of gut disorders by:

  • Affecting secretion in the gut and by reducing gut motility
  • Reducing blood flow to the gut in addition to negatively affecting the formation of new cells and the repairing of damaged cells.
  • Having a damaging effect on gut microbes, usually the beneficial ones
  • Reducing nutrient absorption and the number/quality of digestive enzymes

FACT: Mouse studies show that short-chain fatty acids (SCFAs) may help to normalize the leakiness in not just your gut lining, but your “brain lining” (e.g. “blood-brain barrier”) too.

Several studies have found patients with inflammatory gut conditions experience a worsening of symptoms after stressful events. Chronic, or long-term, stress and depression are associated with more gut pain, leaky gut, and other inflammatory gut conditions like Crohn’s and ulcerative colitis. 

We used to think that only the brain sent instructions and commands down to control all parts of the body. However, we are now learning that a lot of the communication between the gut and the brain starts in the gut and goes up to the brain via what is known as the vagus nerve. Several studies show that in about half of people studied, gut symptoms arose before the mood issues did. This makes sense when you see that the gut makes neurotransmitters, not just the brain as previously thought, and is able to communicate directly with the brain.

Stress and the Gut Microbiome in Leaky Gut

Stress can affect changes in the microbiota and the lining of the gut, as well as further increasing gut inflammation. In animals, studies show being under stress increases intestinal permeability, a.k.a. leaky gut and inflammation.

It has also been shown that probiotics (food and or supplements with good bacteria), and prebiotics (food for the bacteria) actually affect the brain by reducing anxiety, and creating a more positive aky gut and inflammation.

outlook. These probiotics and prebiotics can also help reduce levels of stress hormones like cortisol, which is wonderful.

Mental Health and Gut Health in Leaky Gut

People who have gut disorders have a higher risk of developing anxiety or depression. Sometimes experiencing symptoms like abdominal pain, bloating, and discomfort can affect the quality of life and moods of people who have inflammatory bowel disease or any type of gut problems.

Some animal models of the inflammatory gut condition colitis showed behavioural changes that are similar to mood disorders in people. Also, mice given a short-chain fatty acid (SCFA) called butyrate, which is produced in the large intestine, seemed to experience an antidepressant effect. These links between the gut and mental health are because of the “microbiota-gut-brain axis.” This axis includes many connections between the two of them, including through your nerves and hormones.

When the areas of the brain associated with stress are activated, this initiates the stress response, which is a twofold response. Firstly, it initiates the release of stress hormones (hypothalamic-pituitary-adrenal axis or HPA axis) that affect the whole body. Secondly, it causes the activation of the “fight or flight” (sympathetic system) part of the body’s autonomic nervous system. Both the hormones and autonomic nervous system affect the gut, and this can affect all three layers of the gut lining.

One of the key stress hormones of this HPA-axis is from the adrenal glands (the “A” in HPA). It’s the infamous stress hormone called cortisol. Cortisol is released into the bloodstream when you are under stress. Cortisol directly affects the gut by reducing your ability to properly digest food, and instead prioritizes your survival. It essentially prepares for “fight or flight” by slowing down the “rest and digest” functions.

How Do I Destress?

Learning how to manage your stress levels and de-stress has never been more important. Participating in an activity you enjoy will have you well on your way to being less stressed, while also keeping your gut microbes happy and healthy.

Find an activity you enjoy such as: 

  • Playing tag with your children, if you have any
  • Meditating
  • Dancing around the house using your hairbrush as a microphone (I so do not do that, not all the time anyway)
  • Having regular massages

FACT: Mouse studies show that short chain fatty acids (SCFAs) may help to normalise the leakiness in not just our gut lining, but our “brain lining” (e.g. “blood-brain barrier”) too.

What you can do about leaky gut?

Healthy foods for leaky gut

When your “good” gut microbes are happily eating their favourite foods they have positive effects on your gut. This is by crowding out the “bad” microbes and producing beneficial anti-inflammatory compounds like SCFAs.

FACT: The type of microbes that live in your gut is established by the time you’re 3-5 years old. About 30-40% of it can be influenced by factors such as diet.

According to Aguayo-Patron, 2017:

“Diet is the main factor that influences gut microbiota composition.”

There are a few things you can do to enhance your gut health to improve your overall health.

1. Eat More Fresh, Unprocessed and Minimally Processed Foods for Gut Health

We’re talking things like:

  • Fruits and vegetables
  • Nuts and seeds
  • Properly prepared whole grains and legumes, if tolerated
  • Dairy products, especially fermented ones like yoghurt
  • Fish

This is sometimes referred to as an “old fashioned” or traditional diet. It includes fresh and minimally processed foods that are closer to the way they’re found in nature. These promote a healthy mix of “good” gut microbes. One of the reasons is because these foods contain higher amounts of fibre and “resistant” starch. 

Sugars and easily-digested starches are broken down and absorbed into the bloodstream as sugar. Resistant starches and fibre, on the other hand, are “resistant” to this process and make it all the way through tour intestines to where most of your gut microbes live. These can then become food for your “good” gut microbes and promote their health.

Another possible reason why fresh and unprocessed foods are beneficial is that they’re free of some of the additives used in ultra-processed foods, which unfortunately can affect your gut microbiota negatively.

This leads us to the second thing you can do about leaky gut.

2. Ditch the Ultra-Processed and Fast Foods for Gut Health!

These are the quick and easy foods which usually are:

  • Ready to eat
  • Ready to heat
  • Pre-packaged
  • Convenient
  • Fast
  • Have long and unpronounceable ingredient names

Typically they’re high in calories, trans fats, sugar, salt, contain additives and preservatives, and have a lot of sugar. The easily digested starches in processed foods raise your blood sugar, while also not containing a lot of fibre or resistant starches. In addition, processed foods also tend to be not very filling which prompts you to eat more and more of them. This can quickly lead to obesity if they make up a big and constant part of your diet.

These types of foods also promote inflammation and gut dysbiosis – factors associated with leaky guts! 

Eating less processed foods in favor of fresher, whole foods is associated with:

  • Happier gut microbiota
  • Less inflammation
  • A nice, strong non-leaky gut lining

3. Pay Attention to Potential Food Intolerances for Gut Health

Some gut symptoms may be related to food allergies or intolerances, undiagnosed coeliac disease, or gluten sensitivity. Removing food allergens and gluten from your diet can help. The best way to know if you’re affected is to get tested for coeliac disease. Luckily, there are a lot of gluten-free foods available now, however, ultra-processed gluten-free foods are still ultra-processed and should be avoided in favour of fresh and unprocessed foods.

Also, some people are intolerant of certain carbohydrates called FODMAPS (fermentable oligo-, di-, and mono-saccharides and polyols). These are found in stone fruits, legumes, lactose-containing foods, some vegetables, and artificial sweeteners. Most of these foods are healthy and should not be eliminated from your diet long-term to avoid nutritional deficiencies.

If in doubt, always contact your health professional to see if you should be tested for food intolerances before removing foods from your diet.

4. Reduce Alcohol Intake for Gut Health

Alcohol can stress your friendly gut microbes and can disrupt the function of your three-layered gut lining. Drinking alcohol can cause bacterial overgrowth in the wrong areas, while at the same time reduce some of the friendly “good” microbes like Lactobacillus.

FACT: Some “bad” bacteria, including some species of E. coli, can produce alcohol, which may be one of the ways that they contribute to leaky gut.

5. Consider Probiotics for Gut Health

Probiotics are live microorganisms that have a beneficial effect on human health and as mentioned above, also play a part in stabilizing your moods. Probiotics are found in various fermented foods and are also available as dietary supplements.

You can find probiotics in fermented foods such as:

  • Yogurt
  • Kefir
  • Kombucha
  • Miso
  • Kimchi
  • Fermented vegetables

Infections and the use or overuse of antibiotics, especially during the first months of life, can have a negative effect on gut microbiota. If you have to take an antibiotic, ask your healthcare professional if you should also take certain probiotics to help reduce the impact on your gut microbiota.

Clinical trials are being done to test whether probiotics may benefit inflammatory gut conditions even without antibiotic use. More research is needed to confirm which amounts of which types of probiotics are the most beneficial for which conditions.

CAUTION: Before taking any supplements, make sure to read the label and heed the warnings. If you are taking other supplements or medications or if you have a medical condition, be sure to consult with a knowledgeable healthcare professional first.

Are You Concerned You May Have  Leaky Gut?

Leaky gut, or increased intestinal permeability, is linked with many conditions of the gut, the body, and the mind. While research is still figuring out exactly how this happens and which comes first, there are some steps you can take today to help optimize your overall health.

If you’re concerned you may be suffering from leaky gut or are experiencing gut health issues, I urge you to get in touch with a functional medicine practitioner near you. If you’re in the Preston, Chorley or Blackburn areas and are experiencing the symptoms of leaky gut, click here to get in touch with me. 


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  1. […] than normal due to unwanted gaps that cause a whole host of problems. This article is part one of a two-part series. I hope you enjoy reading along and learn a new thing or two about leaky […]

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