Become more conscious of your dietary choices and care for your brain health.
Nutrition and brain, are they linked?
In recent years, more and more researchers have focused on the link between nutrition and the brain. It has been known for some time that malnutrition leads to growth failure and cognitive deficits. These deficits cause long-term damage as well as diminished quality of life, thus reducing psychological wellbeing. However, we now know that nutrition affects the brain at anatomical levels as well. Studies show an association between nutrition, brain volume and specific structures of the brain that play crucial roles in development.
What is the gut-brain axis?
The gut-brain axis refers to the physical connection between the gut and the brain. The gut microbiota is a collective term given to the micro- organisms living in the human gut. The state of the microbiota has important effects on the brain but also relies a lot on our diet. Let’s get a better understanding of the two main components that balance it.
Prebiotics and probiotics
Prebiotics and probiotics are the two most common components of the microbiota. Prebiotics are indigestible ingredients that are selectively used by microorganisms and promote health benefits. They are typically found in mother’s milk and some cases even added to certain foods. Prebiotics are also naturally present in some fruits and vegetables such as garlic, onions, asparagus, artichokes, tomatoes, and bananas. They are also found in grains, cereals, and nuts such as almonds.
Probiotics, on the other hand, can be seen as the “good” bacteria that keep the human gut healthy. They are living microorganisms that promote health benefits when taken in adequate amounts. They are found in foods such as yoghurt and should be part of our daily diet. They have significant effects on neurological, immunological, and endocrinological levels.
Prebiotics and probiotics work together to maintain homeostasis. Interestingly, these two components affect the brain and mood a lot more than we think.
How does food affect mood?
“This bidirectional communication network includes the central nervous system (CNS), both brain and spinal cord, the autonomic nervous system (ANS), the enteric nervous system (ENS) and the hypothalamic-pituitary-adrenal(HPA)axis.”
The enteric nervous system is an interesting part of this network. Often nicknamed the “second brain”, it is one of the main divisions of the autonomic nervous system and it mainly commands the gastrointestinal tracts. The neurons involved in this system, communicate through neurotransmitters including acetylcholine, dopamine, and serotonin. These neurotransmitters are known for their numerous key functions including mood, arousal, memory, motivation, learning, sexual desire, and reward. Interestingly, they exist in large amounts in the gut and interact with the brain directly.
The body tends to react to stress and unpleasant states by releasing inflammatory responses. But fortunately, studies indicate that nutrition could positively alter these responses. “Psychobiotics” are probiotics that promote a mental health benefit by distinguishing between pro-and anti-inflammatory elements and then, by developing an appropriate immunogenic response. For example, foods enriched with certain families of bacteria such as Lactobacillus families, improve stress related-symptoms including sleep, physical, and mental wellbeing. Lactobacillus is a probiotic present in certain dairy products such as cheese and yoghurt. They are also used in the manufacture of fermented vegetables such as (pickles and sauerkraut), beverages (wine and juices), sourdough bread, and some sausages. Certain dietary fats such as omega-3 fatty acids have also been found to increase the production of anti-inflammatory compounds in the gut. The production of these compounds seems to improve cognitive functioning, mood, anxiety, and depression.
An excellent and recent scientific review discusses in more detail how changes in the gut microbiota were significantly implicated in numerous psychiatric, neurological, and neurodegenerative diseases. This shows, that in addition to the physical health benefits, our dietary choices influence our psychological functioning and well-being by reducing inflammation, stress, and depression-like behaviour.
The Mediterranean diet
A balanced protein, fat, and caloric content has been found to correlate positively with motor and cognitive skills. This balance is often found in diets like the Mediterranean diet. This diet is characterised by a high intake of vegetables, fruits, nuts, and healthy fats such as olive oil. It minimises the consumption of saturated fats and meat. Fish, dairy products, and wine are usually consumed regularly but moderately. The Mediterranean diet shows highly beneficial effects on global cognition and especially in older adults.
People suffering from depression seem to also benefit from this type of diet. A study shows that adults with depression, who changed their dietary behaviour towards a healthier Mediterranean-style diet and supplemented it with fish oil, showed significant improvements in mental health and reduced depression.
Our brains are affected by our dietary choices. Our gut health is not only important for our physical health but also our brain health. It affects our mood and essential psychological functions and influences our quality of life. So next time you go food shopping, think of your brain!