The Connection Between Nutrition and Mental Health: How Food Impacts Your Mood

By Jen Deprez, Psychotherapist at Dalhousie Health and Wellness
We’ve all heard the phrase "you are what you eat," but what does it really mean when we look at how food affects our mental health? While you can’t literally transform into a potato or a piece of chocolate cake, the food choices you make have a profound effect on your emotions, thoughts, and overall well-being.
The Gut-Brain ConnectionThe secret to understanding the relationship between nutrition and mental health lies in a fascinating area of research: the gut-brain axis. This system links your gut (which houses trillions of bacteria, fungi, and viruses) to your brain, influencing everything from mood and emotions to cognitive function. The microbiome in your gut sends signals to your brain that can shape how you feel and think. The foods you eat directly impact the balance of these microorganisms, which in turn affects your mental state.
Food, Microbes, and Mental Well-beingHave you ever felt sleepy after eating a big slice of pizza, or perhaps energized after a smoothie? It’s no coincidence. The microbes in your gut play a significant role in your physical and mental health. Think of the microbiome as the recipe book for your emotional reactions, helping guide the way you feel based on what you put into your body.
Just like the varied ingredients in a recipe come together to create a balanced dish, your gut microbiome is made up of a wide range of microorganisms that work together to regulate your health. Your gut can even act as a defense mechanism, potentially protecting you from a range of psychological issues like anxiety, depression, and ADHD. Studies are increasingly showing the connection between nutrition and mental health, and the results are fascinating.
Diet and Mood: The Importance of Whole FoodsWhile it may be impossible to become a broccoli stalk, a diet rich in whole, nutrient-dense foods like fruits, vegetables, lean proteins, healthy fats, and complex carbs is one of the best ways to support mental clarity and emotional stability. Incorporating foods that are rich in probiotics (like yogurt, kimchi, sauerkraut, and kombucha) can promote a healthy gut microbiome, which fosters a positive interaction between your gut and brain—helping boost your mood.
Just like a high-end car needs premium fuel, your brain thrives on high-quality nutrients. Foods rich in vitamins, minerals, and antioxidants not only support cognitive function but also protect your brain from oxidative stress and inflammation, contributing to overall well-being.
The Role of Serotonin in Mental HealthDid you know that nearly 95% of your body’s serotonin—often called the "happy hormone"—is produced in your gut? Serotonin plays a major role in mood regulation, and maintaining healthy levels is critical to your emotional health. A diet full of nutrient-dense foods supports serotonin production, helping keep your mood stable and your overall mental health on track. On the other hand, diets high in processed foods and sugar can deplete serotonin levels, leaving you feeling sluggish, irritable, and mentally foggy.
Blood Sugar and Mood Swings: A Rollercoaster RideImagine riding a rollercoaster, with your blood sugar levels rising and falling throughout the day. This blood sugar rollercoaster can lead to mood swings, irritability, and energy crashes. Here’s how it works:

• Rising Blood Sugar: This phase often leads to an uplift in mood, heightened concentration, and a sense of well-being, thanks to a surge in serotonin.
• High Blood Sugar: As your blood sugar peaks, you may experience brain fog, fatigue, inflammation, and a general sense of discomfort.
• Falling Blood Sugar: When your blood sugar starts to drop, you might feel anxious, irritable, and mentally unfocused.
• Low Blood Sugar: At the bottom of the rollercoaster, symptoms like shakiness, cravings for sugary foods, irritability, and fatigue can take over.

Maintaining balanced blood sugar levels through nutrient-rich meals can help you avoid these dramatic fluctuations and keep your mood steady.
Traditional vs. Western Diets: Mental Health BenefitsResearch suggests that diets like the Mediterranean or Japanese diets, which emphasize whole foods, vegetables, and healthy fats, may lower the risk of depression by 25-35% compared to the typical Western diet, which is often high in processed and refined foods. These traditional diets focus on foods that support both physical and mental health, while the Western diet, filled with sugars and processed foods, can increase the risk of mood disorders.
Empowering Mental Health through NutritionThe first step toward improving your mental well-being through food is to make sure you’re getting the most nutritional value from your calories. For example, 150 calories from a sugary snack offer little to no nutritional benefit, while the same calories from a piece of fruit or a vegetable provide vitamins, fiber, and antioxidants that support both your body and mind.
Pay attention to how different foods make you feel, mentally and emotionally. Keep a food journal to track what you eat and how it affects your mood, energy levels, and mental clarity. By identifying patterns between your diet and mental health, you can start making more mindful choices.
The Benefits of Clean Eating: A Week Without Processed FoodsOne powerful strategy to boost your mental and physical health is to experiment with "clean eating." For one week, eliminate all processed foods and refined sugars from your diet, and observe the changes in how you feel. Many people report a significant reduction in inflammation, improved energy, and a more stable mood after just one week of clean eating. Afterward, slowly reintroduce foods and note how they affect you.
This exercise can help you become more in tune with your body’s responses to different foods, empowering you to make healthier choices that support both your mind and body.
Conclusion: Nourish Your Mind and BodyThe food you eat holds the power to improve or diminish your energy, mood, and overall well-being. If you truly are what you eat, it’s time to nourish yourself with nutrient-dense foods that support a healthy gut, balanced blood sugar, and optimal mental health. Small changes in your diet can lead to significant improvements in your emotional and physical well-being.
Disclaimer: This article is for informational purposes only and is not a substitute for medical advice. Always consult with your healthcare provider before making any dietary changes.
References:

• Appleton, J. (2018). The Gut-Brain Axis: Influence of Microbiota on Mood and Mental Health. Integrative Medicine (Encinitas, Calif.), 17(4), 28–32.
• Ferraris, C., Elli, M., & Tagliabue, A. (2020). Gut Microbiota for Health: How Can Diet Maintain A Healthy Gut Microbiota? Nutrients, 12(11), 3596. https://doi.org/10.3390/nu12113596
• Selhub, E. (2015). Nutritional Psychiatry: Your Brain on Food. Harvard Health Blog, 16(11), 2015.
• Magesh, P. (2022). Food And Mood-The Interplay Between Nutrition, Mood, Brain, And Behavior. IJO-International Journal of Social Science and Humanities Research (ISSN 2811-2466), 5(12), 01-12.