What is the nature of the relationship between the digestive system and the brain?

How does the digestive system affect the brain?

How does the latter affect the digestive system?

What is the relationship between the digestive system, microscopic microorganisms, the enteric nervous system and health?

Is diet related to mental health?

Will changing the diet cure or alleviate mental health disorders?

We asked these questions to Dr. Muhammad Farhan, assistant professor at the College of Health and Life Sciences at Hamad Bin Khalifa University in Qatar, who answered them in an exclusive interview with Al Jazeera Net.

What is the nature of the relationship between the digestive system and the brain?

When we talk about mental health in general, we only think of the brain;

It is important to point out that mental health does not include only the brain, as the intestines also play an important role in mental health.

Several studies have indicated a close association between mental illness and the brain, including depression, excessive anxiety, and gut disorders.

Farhan: Irritation in the intestine plays a role in sending a stress signal to the brain, which may affect our mood or some of our decisions (Hamad Bin Khalifa University)

How does the digestive system affect the brain and vice versa?

A healthy organism has a homeostatic relationship (internal balance) between all organs, and this relationship is of great importance between the digestive system and the brain, as the brain depends on the digestive system to provide nutrition and essential biomolecules, while the gut depends on the brain for digestion, absorption and excretion.

While the role of the brain in controlling bowel function is well known, recent scientific studies have identified the role of the interrelationship between the gut and the brain, and the extent to which the gut affects the brain.

For example, researchers have been able to discover the role of irritability in the gut in sending a stress signal to the brain, which may affect our mood or some of the decisions we make.

This information is essential because between 30 and 40% of the population may develop problems with stomach function at some point, and these new findings explain the sharp rise in anxiety and depression, which can be linked to an unstable stomach state.

Thus, this studies are very important and necessary for the development of effective new treatments.

What is the relationship between the digestive system, microorganisms, the enteric nervous system and health?

The microbiome plays an important role in many bodily functions, including activating human genes that contribute to the absorption of nutrients, digestion of toxins and sugars, distinguishing between harmless and potentially life-threatening bacteria, and promoting immune response, and even release and enhance neurotransmitters.

The transfer of the microbiome from the mother to the child is necessary because in the absence of a microbiome the child will not be able to digest a certain type of sugar found only in breast milk, a type known as “oligosaccharides”.

And this sugar is only digested by the microbiome with the formation of sialic acid necessary for brain development.

Likewise, multiple molecules secreted by the microbiome affect metabolism.

Hence, identifying the type of gut microbiome that may influence metabolism may identify and reduce risk factors associated with health conditions such as type 2 diabetes.


Is diet related to mental health?

Due to various genetic or environmental factors, a person may have an unbalanced composition of the gut microbiome.

Microbiome disruption is usually associated with depletion and proliferation of anti-inflammatory bacterial species, and an increase in bacterial species.

This pattern of microbiome imbalance has also been observed in patients with major psychiatric disorders, including depression, and excessive anxiety.

These patients usually have fewer microbial species in their gut than their healthy counterparts.

Does changing the diet cure or alleviate mental health disorders?

Anxiety and depression are among the most common mental illnesses in the world, and researchers are constantly studying new ways to reduce the burden of these two diseases. The question here about the extent to which diet or specific nutrition methods can contribute to reducing the impact of anxiety, depression or other mental illnesses is one of the intriguing questions that researchers are trying to answer. More recently, a major meta-analysis looked at 21 studies from 10 countries around the world, comparing whether a healthy, balanced diet that includes fruits, vegetables, whole grains, fish and antioxidants can reduce the risk of depression.

They also analyzed the effects of an unhealthy Western-style diet, which may include red, processed meat, sweets, high-fat diets, and diets low in fruits and vegetables, and whether they were associated with an increased risk of depression.

This study found a 32% reduction in risk when following the Mediterranean diet.

Similarly, several other studies have identified risks related to excessive anxiety in older adults and adolescents who follow a Western-style diet.

Research is needed to better understand the role of the gut or microbiome in human health

The doctor concluded by saying that there are new and exciting perceptions about mental health disorders related to whether changes in diet or changes in the gut microbiome or its metabolites affect mental health, and whether these good bacteria can be cultured directly and mixed in vital aids such as yogurt to treat mental illness. common.

More research is needed to determine the mechanism by which different types of bacteria and bacterial products affect mental health.

And it must be remembered that most published studies may not prove the etiology, treatment, or improvement of the disease.

More long-term research is needed to determine the best dietary patterns for treating mental health conditions.

Dr. Mohammed Farhan is an assistant professor at Hamad Bin Khalifa University.

His lab at the College of Health and Life Sciences is taking the lead in understanding the molecular mechanisms through which microbiome changes are linked to brain disease.


What is the Mediterranean diet?

It is a common diet in countries located on the Mediterranean basin such as France, Italy, Spain and Greece, and is based on healthy foods such as legumes and olive oil, and is associated with benefits on the body.

The foundations of the Mediterranean diet are:

  • Eat mainly plant foods, such as vegetables, fruits, whole grains, legumes and nuts.

  • Eat at least 5 servings per day of vegetables and fruits, and the portion equals a medium fruit or half a cup of vegetables or fruits, or a cup of chopped green leafy vegetables.

  • Eat rice and whole pasta.

  • Eat potatoes with their skin to increase the intake of dietary fiber.

  • Eat an amount of nuts that does not exceed the full amount of your hand per day, because they are rich in calories, although the majority of their fats are unsaturated (healthy).

    And avoid nuts with sweets, such as chocolate, roasted with honey, or with a lot of salt.

  • Pulses are a source of vegetable protein, including chickpeas, fava beans, beans and lentils.

  • Use herbs and spices instead of salt in cooking and food.

  • Use a healthy oil, such as olive and canola oil, in place of butter, margarine, and animal fats.

  • Reducing the intake of red meat to only a few times per month.

  • Eat fish and poultry at least twice a week.

  • Eat with family and friends instead of alone, while watching TV, mobile, or at work.

  • Doing sports and enjoying physical activity.