By Tala Zakhour, dietetic stagiaire at Openspace Clinic

Our body contains connections between our gut and our brain. Our gut is sometimes called the “second brain”.

In fact, 95% of serotonin, a neurotransmitter that regulates mood, appetite, and sleep, is produced by bacteria in our large intestine.
Knowing that there is a connection between our gut and our brain, let’s dive into how certain food items can affect our mood.

Let’s first start with the basics:

Why do we need to eat?
Food is like fuel for our bodies. Just like a car needs gas to run, our bodies need food to work properly. Moreover, the food we eat provides us with essential vitamins and minerals that can play a significant role in our mental and physical well-being. This ensures us with the necessary energy and nutrients needed to feel our best when facing challenges throughout our day.

Let’s look at the Canada Food Guide (CFG) and its recommendations for a balanced plate.

It suggests filling ½ of the plate with vegetables and fruits, ¼ of the plate with protein-rich food, ¼ of the plate with whole grains, and making water our drink of choice.
The idea is that our body needs all these different food groups to have a diverse range of nutrients which provides us with the energy we need to carry out our daily tasks.

Let’s take a closer look at these different food groups and their impact on our mental health.

Starting with vegetables and fruits:
Phytonutrients are naturally occurring antioxidants in fruits and vegetables that give them their beautiful and rich colors. Vegetables and fruits are filled with antioxidants and phytochemicals which help decrease inflammation and repair damage to the cells of our brain.
– An easy way to make sure we are getting a good amount and variety of antioxidants is by trying to add as many colors as possible to our plate. Try to eat the rainbow!

Fun Fact: Did you know?
Certain food items such as apples, kale, berries, grapes, onion, and green tea have high levels of quercetin which is a phytochemical that increases the amount of dopamine, serotonin, and norepinephrine in our brain. These are all neurotransmitters that are involved in mood regulation!

Moving on to protein-rich of food:
There is a wide variety of food items rich in protein such as legumes, poultry, meat, fish, shellfish, eggs, dairy products, nuts/seeds, tofu, and soy products.
Having protein in each meal is important because it contains amino acids which are the foundation needed to produce the key neurotransmitters involved in mood regulation.

As for whole grain:
They are found in food items such as brown/wild rice, oats, quinoa, barley, and so on and offer
multiple health benefits. They are a rich source of B vitamins which help boost our mood and energy. Whole grains are also a rich source of tryptophan. According to Nutrition Australia (2018), tryptophan is an amino acid needed to produce serotonin, the “feel-good hormone” helping to regulate our mood and sleep.

How about fats?
Although fats are not a food group presented in the CFG, choosing products rich in healthy fats, such as nuts/seeds, avocados, fatty fish, soy products, and so on, is essential in a balanced diet. Omega-3, a healthy fat, can be found in many of the products stated above. However, the omega-3 specifically found in fish, seafood, and fish oil, has potentially the most benefits in improving our brain function and interacting with mood-related molecules. According to the Association of UK Dietitians (2020), omega-3 fats may help reduce low mood states in adults.
Fun Fact: Did you know?
-Fat makes up 60% of our brain.

Nutritional practices affecting our well-being:
The CFG also emphasizes the fact that taking care of ourselves doesn’t only stop at the kind of food we eat. It is so much more than that! It is also about where, when, why, and how we eat. Cooking more often and being present in the moment enjoying meals with friends, family, co-workers, and/or neighbors is also part of self-care. It can also be quite beneficial to have a certain consistency in our eating times. Eating something every 3-4 hours, helps to keep our muscles and brain well-nourished and our energy levels stable, which can positively affect our mood. This approach prevents having our blood sugar drop which may lead to feeling irritable and tired. According to an article featured in the British Journal of Nutrition, adequate hydration has also been shown to have a positive effect on our mood.

In short, by paying attention to what we eat, we can have some influence on our mental well-being, thanks to the gut-brain connection. This is an additional way to take control of our mental health.



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McManus, K. (2019, April). Phytonutrients: Paint your plate with the colors of the rainbow. Harvard Health Publishing – Harvard Medical School.

Głąbska, D. et al.(2020). Fruit and Vegetable Intake and Mental Health in Adults: A Systematic Review. Nutrients, 12(1), 115.

Physicians Committee for Responsible Medicine. (2023). Food and Mood: Eating Plants to Fight the Blues.

Lierberman, H. – Institute of Medicine (US) Committee on Military Nutrition Research. (1999). Amino Acid and Protein Requirements: Cognitive Performance, Stress, and Brain Function. The Role of Protein and Amino Acids in Sustaining and Enhancing Performance. National Academies Press (US) – Chapter 14.

The Association of UK Dietitians. (2020, August). Food and Mood.

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Mischoulon, D. (2020, October). Omega-3 Fatty Acids for Mood Disorders. Harvard Health Publishing – Harvard Medical School.

Chang, C. Y., Ke, D. S., & Chen, J. Y. (2009). Essential fatty acids and human brain. Acta neurologica Taiwanica, 18(4), 231–241.

Government of Canada. (2023, November). Canada’s Food Guide.

Nutrition Australia QLD Division. (2018). How Food Can Affect Your Mood.

Masento, N. et al. (2014). Effects of hydration status on cognitive performance and mood. British Journal of Nutrition, 111(10), 1841-1852.