How Nutrition and Hydration Impact Mental Health (& How to Make Changes that Last)

Have you ever thought about how what you put on your plate affects your mood and mental health? Could feeling moody, low, or fatigued have something to do with the foods you eat? The answer is yes. Your diet might be playing a bigger role than you think.

As Registered Social Workers and therapists in Saskatoon, we've seen time and again how people are amazed to learn that their mental health issues can sometimes be traced back to their eating and drinking habits. In this post, we'll explore the science behind how nutrition and hydration affect mental health, look at what foods to eat more (and less) of, and offer realistic tips for creating sustainable, long-term changes in your diet.

The Science Explains How Nutrition and Hydration Impact Mood and Mental Health

The brain is a high-energy organ that uses about 20% of our daily calorie intake. Pretty incredible for a relatively small organ, right? Your brain needs a steady supply of nutrients, including vitamins, minerals, amino acids, and healthy fats, to function well. And here's how nutrition connects to mental health.

The Brain-Boosting Power of Omega-3s and Key Nutrients

Studies show that adequate omega-3 fatty acids, healthy fats found in foods like fish and nuts, contribute to improved cognitive functions, like memory and attention, and can protect us against neurodegenerative diseases like Alzheimer's.

Omega-3s play a key role in ADHD. Studies show that children with ADHD tend to have lower levels of omega-3 in their bodies, and adding omega-3 supplements to their diet has been shown to bring small but noticeable improvements in symptoms.

Research also shows that chronic inflammation in the brain can disrupt mood-regulating chemicals and pathways, contributing to depression. Omega-3 fatty acids might help reduce this brain inflammation, offering a possible treatment path for depression.

In addition to omega-3s, iron, zinc, and vitamin D are vital for neurotransmitter synthesis and overall neural health. The deficiencies in these nutrients are associated with attention, focus, and impulse control challenges.

The Gut-Brain Connection

Science shows that our diet has a powerful influence on how we feel, not only physically but also emotionally. The food we eat affects serotonin (often called the "feel-good" chemical), a brain chemical that helps regulate mood and stress response. Low levels of serotonin and disrupted serotonin signaling in the brain can lead to mood disorders and depression.

About 90% of the serotonin in our bodies comes from the cells lining our gastrointestinal tract and is then released into the bloodstream. Since most of our "feel-good" hormone is linked to what we eat, our diet can change how we feel.

Hydration and Brain Function

Even mild dehydration itself (only 1-2% fluid loss) has been demonstrated to impair concentration, increase feelings of anxiety, and lower mood. Being well-hydrated protects intellectual function, concentration, and emotional stability.

Sustainable Diet Changes for Mental Health

Supporting your mental health and well-being through nutrition basically means focusing on foods that nourish your brain and body. Here's a breakdown of the foods you should be eating more of and the ones you should steer clear of.

The Foods to Include in Your Diet

Healthy Fats and Whole Foods

The Mediterranean diet, known for its heart and brain health benefits, is naturally rich in healthy fats, antioxidants, and fibre. Research shows it can help support brain development and lower stress, anxiety, and depression symptoms.

Omega-3 fatty acids, found in fatty fish (like salmon, mackerel, and sardines), flaxseeds, and walnuts, are known to improve mood and reduce symptoms of depression. Also, prioritize whole, minimally processed foods like vegetables, fruits, legumes, whole grains, nuts, and seeds. These foods provide fibre, antioxidants, and phytonutrients that reduce inflammation and support brain health.

Lean Proteins and Fermented Foods

Eggs, poultry, tofu, lentils, and beans supply amino acids necessary for neurotransmitter production. Additionally, foods like yogurt, kefir, or miso help support gut health, which in turn supports brain health.

Water

Aim for about 2-3 litres of water daily (more if you're active) to stay hydrated and keep your brain functioning optimally.

What to Eat Less Of

Certain foods and drinks are linked to poorer mental health outcomes when you consume them excessively.

Refined Sugars and Processed Foods

Refined carbohydrates like sweet treats and drinks cause rapid fluctuations and blood sugar rises, leaving you tired, grumpy, or on edge. Similarly, ultra-processed foods can increase inflammation and negatively impact the gut microbiome, leading to mood disturbances.

Caffeine

While moderate caffeine consumption improves alertness, high consumption increases anxiety and sleep disturbance, both of which impact mood.

Alcohol

Alcohol is a depressant and can interfere with neurotransmitter balance, sleep, and hydration.  Regular, excessive drinking of alcohol is closely linked to mental health issues.

Sustainable Changes: How to Make It Last

Do you find that, despite your best intentions, your healthy eating habits usually don’t stick? Most of us have set big wellness goals or resolutions, only to watch them fade away within a few weeks. If this resonates, you should not feel bad about yourself. Changing our diet can really feel overwhelming. A busy lifestyle, a lack of time, or feeling overwhelmed by making big changes at once can all put our motivation to the test.

Start Small

Deciding you’ll never eat cake or pasta again can leave you feeling depressed and moody. And let’s be honest, it’s just not realistic. Don’t try to take on too much too quickly. Instead, focus on one or two things. For example, try to drink an extra glass of water each day or reduce sweets.

Plan Ahead

Healthy choices are easier when you're prepared. Create simple meal plans for the week and shop in advance (ideally, for locally produced goods).

Get Support

Social support can help you feel less isolated when making such an important health change. Plus, it raises accountability. So, share your goals with your partner, friend, or family member.

Be Patient

Changes that last take time. Be kind to yourself, and celebrate every small step.

One Size Doesn't Fit All

Trying to do it perfectly or relying on willpower alone rarely leads to sustainable change. Lasting change comes from setting small, manageable goals. When you make gradual adjustments and build habits that fit realistically into your daily life, you create a foundation for change that is far more likely to last over the long term.

However, remember that nutrition is very individual. What works for one person absolutely may not work for someone else. The best approach is to listen to your body and make changes that resonate with your unique needs.