The Gut Brain Connection

Digestive Problems: An Overlooked Cause of Mental Health Problems

There is a definite gut brain connection and problems associated with the gut can have serious effects on mental health conditions such as depression and anxiety. Digestive problems and its impact on mental health are, however, commonly overlooked by mental health practitioners despite studies showing a strong relationship between gastrointestinal disorders and mental health. For example, many studies have shown strong links between depression and celiac disease, poor diet and depression, food allergy and depression, candida (yeast overgrowth) and depression, plus many more. This page provides an overiew of digestive problems and its association with mental health problems.

It is through our digestive system we obtain the nutrients our body needs to survive.  Vitamins, minerals, amino acids, fatty acids and many more are primarily obtained from the foods that we eat and fluids that we drink. However, when our diet is lacking and/or our digestive system is not working optimally, nutrient deficiencies and a range of inflammatory/ immune responses will occur. This can lead to a whole array of health problems including mental health disturbances such as depression, anxiety and even schizophrenia.

Therefore in order for the mind to be functioning properly, the whole body needs to be working properly — including the gut!  Don’t forget the Gut Brain Connection!

Studies actually show that people with digestive-based problems and diseases (e.g., coeliac disease, Crohn’s disease, irritable bowel syndrome) are significantly more likely to suffer from mental health problems. For example, a review study showed that psychiatric disorders such as major depression, anxiety, and somatoform disorders (mental disorder characterised by physical symptoms that mimic physical disease or injury for which there is no ‘identifiable physical cause’) occur in up to 94% of people with irritable bowel syndrome. Unfortunately, the gut brain connection and digestive disturbances are regularly overlooked in mental health treatment.

Gut Brain Connection – Symptoms/ Signs of Gastrointestinal Problems

Because our digestive system is so important, problems in this area can lead to an almost endless array of signs of symptoms. It is often said that everything comes from the gut and therefore if there is a problem in the gut, the whole body will be adversely affected.

Although far from exhaustive, below are some of the symptoms of digestive problems:

  • Stomach bloating

  • Nausea

  • Flatulence/ wind

  • Diarrhoea

  • Constipation

  • Stomach pain

  • Allergies

  • Heartburn

  • Pain or aches in joints

  • Itchiness

  • Dizziness

  • Weight loss/ gain

  • Nervousness

  • Brain fog

  • Poor memory and attention

  • Headaches/ migraines

  • Skin problems such as rashes, eczema, and psoriasis

  • Pins and needles

  • Brittle nails

  • Recurrent urinary tract infections

  • Fatigue

  • Health conditions – gastrointestinal problems can increase the risk of a range of health conditions including thyroid diseases, certain cancers, anaemia, iron deficiency, diabetes, hypertension, arthritis, osteoporosis, cardiovascular disease, mental health conditions, plus many more

Modifiable Causes of Gastrointestinal Problems: Improving the Gut Brain Connection!

Below are some of the common causes of digestive problems that require assessment and treatment if someone presents with mental health problems and digestive complaints:

  • Food allergies/ intolerances. Many of us regularly eat foods that we are intolerant to. While this may be fine for some people, for others the consumption of these allergic/intolerant foods can lead to significant physical and mental problems. For many people, a specific food allergy and depression are strongly interlinked.

  • While identifying major allergies can be simple (such as in immediate peanut allergies) for other food intolerances, identifying the problem food can be more difficult. This is because for many people, the effects of the ‘intolerant food’ may not occur for up to 72 hours after the food is eaten. Common intolerant/allergenic foods include: wheat/gluten, milk/dairy, corn, soy products, eggs, and nuts. There are a number of tests available to help identify food allergies and intolerances. Of specific concern is the link between irritable bowel syndrome (IBS), celiac disease/ gluten intolerance and depression / anxiety.

  • Medications. Many medications can cause digestive problems. For example prolonged use of non-steroidal anti-inflammatory drugs (NSAIDs medications containing ibuprofen) and aspirin are common culprits.  Oral contraceptives, antidepressants, cholesterol lowering drugs, chemotherapeutic drugs, diuretics and blood thinning drugs can also cause gastrointestinal problems. When used for prolonged periods, many medications used to treat digestive problems can also cause digestive problems. In particular, medications that reduce acid levels in the gut (proton pump inhibitors e.g., Nexium, Zoton, Losec, Pariet) and over-the-counter antacids are major culprits.

  • Parasites and other pathogens. Many people can contract certain parasites and other intestinal pathogens which can cause havoc on the digestive and immune system, and can have ramifications throughout the whole body. There are now reliable tests that can identify specific pathogens. If you have long-standing digestive problems, you must test for and eradicate pathogens

  • Digestive enzyme deficiencies. In order for our body to digest food, it requires a range of digestive enzymes. For many people with digestive problems, digestive enzyme levels may be deficient, resulting in poor digestion. For example, a common enzyme that is lacking for many people is the enzyme lactase which is required to absorb lactose in milk. This results in ‘lactose intolerance’. However, there are other enzymes required to break down fats, proteins and starches and when lacking will affect our digestive system and ability to absorb crucial nutrients.

  • Stomach acid problems. Stomach acid (hydrochloric acid or HCl for short) is excreted by specialised cells to help our body digest proteins and minerals, and sterilise foods. For many people, levels of HCl can be low resulting in poor protein absorption. Protein provides us with amino acids which are the building blocks of brain neurotransmitters important for mood (e.g., serotonin, dopamine).Heartburn is a symptom experienced by many people and it is commonly believed that it is caused by too much stomach acid. However, for at least 50 percent of people suffering from heartburn, it is actually caused by not enough stomach acid. As a result of stomach acid deficiency, food remains in the stomach for too long which leads to heartburn. The irony of the situation is that antacids are then used to reduce stomach acid and symptoms of heartburn, and while effective in the short term in reducing heartburn, in the long run prolonged use of antacids further exacerbates digestive problems

  • Bacterial imbalances (dysbiosis). Our digestive system contains billions of bacteria (or gut flora) that have many crucial roles in our body including pathogen defence, digestion, and synthesis of vitamins. There are many species of gut flora and when in healthy balance work in harmony. However, when imbalances, deficiencies or overgrowth in certain species of bacteria occur, digestive problems result. Dysbiosis is also associated with yeast overgrowth (often termed Candida). This bacterial imbalance is termed dysbiosis and can be caused by intestinal microbes, ageing, diet, drugs (especially antibiotics and proton pump inhibitors) and stress. To optimise digestive health and therefore, one’s mental health, gut flora levels needs to be in balance. Gut flora levels and dysbiosis can be tested through stool tests. 

  • Intestinal permeability (leaky gut). Our gastrointestinal system has a mucosal barrier that protects our internal system (e.g., heart, lungs, brain) from ‘outside world’ pathogens. This mucosal barrier consists of tightly joined cells (tight junctions) that allow certain nutrients to be absorbed. When a disruption in these tight junctions occur, many dietary and bacterial substances and other toxic by-products can get ‘leaked’ into the bloodstream leading to an’immune reaction’ causing an array of symptoms, some of them mental. Leaky gut can be caused by poor diet, NSAIDs, food intolerances/ allergies, medications, Coeliac disease, Crohn’s disease, stress, aging, excessive alcohol use, malnutrition and many more. Tests are available to assess the presence of leaky gut

  • Excessive, prolonged stress. Research shows that stress can have a negative effect on our digestive system and can impair rates of healing. Excess stress can also lead to poor lifestyle and dietary habits (e.g., increased sugar consumption, alcohol use etc) that can exacerbate digestive problems. A cycle then develops where digestive problems exacerbate stress. This increased stress then further worsens digestive problems. And the cycle goes on and on.

Treating Gastrointestinal Problems To Improve the Gut Brain Connection

If you are suffering from mental health problems and believe that digestive problems may be causing or contributing to your mental health problems, below are the steps to fix your gut. To adequately heal your digestive system it is recommended that you consult with a health professional knowledgeable in’gut healing’.

Steps to Gut Healing and improving the gut brain connection

  • Identify and remove allergenic/ intolerant foods from the diet

  • Remove/ minimise unnecessary medications

  • Improve overall diet

  • Reduce stress levels

  • Identify and eradicate parasites, pathogens, bacterial overgrowth, yeast overgrowth/ Candida

  • Supplement with digestive enzymes (if low)

  • Supplement with hydrochloric acids (if low)

  • Restore healthy bacteria with pre- and pro-biotics

  • Heal the leaky gut

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