How diet affects mental health through the gut-brain axis
When it comes to mental health, it is important to stress that it is not just about the absence of mental illness. Mental health refers to our emotional, psychological, and social well-being, and is crucial for daily functioning, decision-making, and building relationships.
As we grow and age, our brains undergo natural changes that affect how they function. While some changes are inevitable, there are ways to keep the brain healthy and functional for as long as possible.
The main changes that occur are related to a decrease in brain volume, particularly in areas associated with learning and memory. Very often, there is a reduction in blood flow, which slows down the transmission of signals between neurons. As the production of neurotransmitters decreases, the risk of atherosclerotic plaques, which can lead to the development of neurodegenerative diseases, increases.
All these changes are reflected in a slowing of cognitive function, lower speed of information processing, memory problems, and mood changes. As a result, we find it harder to learn and remember, we take longer to respond to stimuli, and we often experience anxiety, depression, and irritability.
What can we do?
Although the ageing of the brain is a natural process, there is much we can do to slow it down and keep the brain healthy:
– Mental stimulation: reading, learning new languages, solving puzzles, playing chess or other games that stimulate the brain.
– Physical activity: regular exercise increases blood flow to the brain and stimulates the formation of new neurons.
– Social interaction: staying socially connected helps reduce stress and stimulates cognitive function.
– Healthy diet: a diet rich in fruit, vegetables, wholegrain cereals, nuts and fish can help protect the brain.
– Enough sleep: sleep is vital for strengthening and repairing the brain.
– Stress management: relaxation techniques such as meditation and yoga can help reduce the damaging effects of stress on the brain.
It is also important to note that each brain is unique and that ageing manifests itself differently in each person.
This article will focus on diet, as it is an important factor that we can easily influence.
Increasingly, we hear that there is a link between what we eat and our mental health. There is a growing body of research confirming the link between diet and our emotional state.
But how does food affect the brain?
The human brain consumes a huge amount of energy, most of which comes from food. From memory and learning to our mood and emotional stability – it all comes down to the nutrients we consume.
Some nutrients, such as unsaturated omega-3 fatty acids, B vitamins, magnesium, and zinc, are vital for the proper functioning of neurotransmitters. Insufficient intake of these nutrients can result in mood disorders, reduced concentration, and an increased risk of depression and anxiety.
The gut is our second brain
There is growing evidence of a strong link between the gut and brain – the gut-brain axis. The bacteria in our intestine produce neurotransmitters that influence our mood and behaviour. Remarkably, as much as 90% of serotonin, dopamine, and gamma-aminobutyric acid (GABA) is produced in the gut. A diet rich in fibre and probiotics boosts the growth of beneficial gut bacteria, which can positively affect mental health. If the diet is high in fibre and probiotics, fermentation takes place in the gut, producing postbiotics – bioactive compounds that have a number of health benefits.
The gut-brain axis is a key mechanism through which microorganisms in the gut microbiome can influence brain function. During the fermentation of fibre-rich foods, microbes produce metabolites that are called postbiotics. According to numerous studies, postbiotics play a role in this complex interaction between the gut and brain.
Which foods are good for the brain?
– Unsaturated omega-3 fatty acids: found in oily fish (salmon, mackerel, sardines), nuts, and seeds. They help reduce inflammation and improve cognitive function.
– B vitamins: important for the production of energy and the synthesis of neurotransmitters. They are found in wholegrain cereals, legumes, green leafy vegetables, and meat.
– Magnesium: helps regulate mood and reduces anxiety. Good sources of magnesium include seeds, nuts, legumes, and leafy vegetables.
– Zinc: important for learning and memory. It is found in meat, seafood, seeds, and legumes.
– Probiotics: beneficial bacteria found in yoghurt, kefir, and unpasteurised pickles. They support a healthy gut microbiota.
Experts also recommend specific diets that support mental health.
– Mediterranean diet: rich in fruits, vegetables, wholegrain cereals, olive oil, fish, and nuts.
– The MIND diet: based on brain-protecting foods such as green leafy vegetables, berries, nuts, wholegrain cereals, and olive oil.
The MIND diet is a nutrition programme that combines the Mediterranean diet and the DASH (Dietary Approaches to Stop Hypertension) diet. Its objective is to improve cognitive function and reduce the risk of dementia, particularly Alzheimer’s disease.
The main features of the MIND diet are as follows:
– More plant-based foods: the emphasis is on the consumption of fruit, vegetables, wholegrain cereals, nuts, and legumes.
– Less meat and dairy: the diet includes less meat and dairy products, but does not completely exclude them.
– Inclusion of healthy fats: the main source of fats is olive oil.
– Moderation of alcohol consumption: up to one glass of wine per day is acceptable.
Eggs can be eaten as part of the MIND diet. Some studies have shown that eating eggs can slow cognitive decline in healthy adults.
Research has also confirmed that the MIND diet can reduce the risk of dementia, improve cognitive function, reduce the risk of cardiovascular disease, and even help in maintaining a healthy body weight. The MIND diet is a simple and effective method for improving mental health and reducing the risk of neurodegenerative diseases.
While food is not a miracle cure for mental health problems, it can be an effective tool for improving psychological well-being. A balanced and nutrient-rich diet can promote well-being, reduce stress levels, and improve cognitive function. However, it should be stressed that diet is not the only factor that affects mental health. Physical activity, getting enough sleep, maintaining social contact, and managing stress should not be overlooked, as these factors are also very important for mental health.
Sources:
- Hrvatsko društvo za prehranu
- Mentalno zdravlje.hr
- PubMed(baza znanstvenih članaka)
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- National institute on aging
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