Can your diet improve your mental health?

But can the right diet really help with bettering our mental health or is it just another wellness trend? Registered nutritionist Zara Hiridjee helps us explore the science behind it, what to eat for a better mind, and what to avoid.

Why eating a balanced diet is good for your mental health

Gut-brain axis

To begin to understand the relationship between food and mental health, you need to understand the gut-brain connection. This is often known as the ‘second brain’ and is a communication network involving the brain, the gut’s nervous system and the gut microbiome. The connection essentially produces neurotransmitters like serotonin and dopamine (those mood-regulating chemicals), and when we nourish our bodies with the right foods, we are providing these transmitters with essential nutrients.

“A well-balanced diet provides the essential vitamins, minerals and macronutrients that help regulate neurotransmitters like serotonin and dopamine which directly impact mood, motivation and stress resilience,” explains Hiridjee. “For example, omega-3 fatty acids support brain function and have been linked to lower rates of depression and anxiety. Similarly, B vitamins, especially B12 and folate, play a role in energy production and cognitive function with deficiency sometimes leading to low mood and fatigue.”

Blood sugar spikes

Another major factor linking diet and mental health is blood sugar regulation. When we consume foods high in refined carbohydrates and sugar they can cause a spike in blood sugar levels followed by that inevitable crash. This roller coaster effect can lead to mood swings, irritability, fatigue and difficulty concentrating.

“Therefore, a diet rich in fibre, protein and healthy fats can help to prevent these spikes and crashes and hopefully contribute less to irritability and brain fog,” adds Hiridjee. “Complex carbs like wholegrains and legumes provide a steady release of energy and are crucial for serotonin production, which is why extreme low-carb diets can sometimes negatively impact mood.”

A good relationship with food

It’s not just about what we eat – our relationship to what we consume is also important. Restrictive diets or diets containing lots of heavily processed foods can also contribute negatively to your mental health.

“Instead, it’s all about a balanced approach where nutrition meets enjoyment and flexibility supports not just physical health but also a healthy mindset around food,” adds Hiridjee.

Foods you should be eating

Like most things, it’s all about balance in your diet, getting the right amount of nutrients that can have a positive impact on your mental wellbeing. It’s important to remember here that this is just a guide, with suggestions for foods you could be incorporating. For some, this may not feel completely achievable, especially if you’re feeling unwell.

Omega-3 fatty acids

“Omega-3 is crucial for brain health, reducing inflammation and supporting neurotransmitter function. Great sources of this include oily fish like salmon and mackerel, as well as flaxseed, chia seed and walnuts.”

High-quality protein

“Eggs, poultry, lean meats, dairy, tofu, lentils and beans are all good sources of protein. Protein provides amino acids that help produce neurotransmitters like serotonin and dopamine which regulate mood.”

Complex carbohydrates

“Wholegrains like brown rice, quinoa, oats and wholemeal bread provide slow-releasing energy and support serotonin production, which can help with mood stability.”

Fermented foods and prebiotics

“As mentioned already, the gut brain connection plays a major role in mental health. Probiotic-rich foods like natural yogurt, kefir, kimchi and sauerkraut help maintain a healthy gut microbiome while fibre-rich foods, and prebiotics like onions, garlic and bananas feed beneficial gut bacteria.”

B Vitamins

“B Vitamins, especially B12 and folate, are essential for energy production and brain function. These are found in eggs, meat, fish, leafy greens, legumes and fortified foods.”

Magnesium and zinc

“This is important for stress regulation, brain function and reducing anxiety. Magnesium is found in dark leafy greens, nuts, seeds and wholegrains, while zinc is abundant in shellfish, beef, poultry, and chickpeas.”

Healthy fats

“The brain is about 60% fat so including good fats can support cognitive function. Sources include good-quality olive oil, avocado, nuts, seeds, oily fish, and full-fat dairy.”

Hydration

“Even mild dehydration can lead to fatigue and brain fog. Water, herbal teas and naturally flavoured options like cucumber or mint-infused water are great for staying hydrated.”

Foods to avoid

In the case of diet and mental health, it isn’t about avoiding or restricting foods, especially if your mental health makes it harder for you to change up your diet.

“It’s not a case of good versus bad, it’s about balance, moderation and how certain foods affect us over time,” adds Hiridjee. “The issue isn't necessarily eating these foods occasionally but rather relying on them in excess or as a staple in the diet.”

Refined sugars and highly processed food eaten in large quantities can become an issue if they’re leading to blood sugar spikes and crashes, as these can contribute to mood swings. Highly processed foods are also often stripped of fibre and essential nutrients, meaning they don’t provide sustained energy or nourishment for brain health.

Caffeine for many can also be a mental health trigger, especially later in the day when it may overstimulate someone’s nervous system or heighten feelings of anxiety like heart palpitations. Again, this is about understanding how it affects you individually. Some may be fine with a coffee later in the day, but for others, switching to a lower-caffeine option might help.

Mental health and alcohol

It’s probably not surprising to learn just how badly regular alcohol consumption can affect your mental health, especially as its negative effects have been documented and researched enough. While for some an alcoholic drink may feel like a stress reliever, the long-term effects it can have on brain chemistry, mood stability and wellbeing can be quite significant.

“One of the biggest issues is how alcohol affects neurotransmitters. Initially it can trigger a short-lived boost in mood, but over time regular alcohol use disrupts the balance of these chemicals, leading to increased anxiety, low mood and even depression,” explains Hiridjee.

“Essentially it depletes the very neurotransmitters that help regulate emotions, leaving you more vulnerable to mood swings and emotional lows once the effect wears off. There's also the impact it has on your sleep, its effect on gut health and the fact it's a depressant, meaning it slows down brain function and impairs the body's stress response.”

While food plays an important role in mental health, it is not a cure all. A balanced diet can support emotional wellbeing, but it should be part of a broader strategy including exercise, sleep, mindfulness and social connections. It's also important to stress here that while nutrition does play a key role in mental wellbeing it's important to maintain a flexible, balanced approach to eating. Developing an overly strict mindset around 'good' and 'bad' foods can contribute to stress, guilt, and even disordered eating patterns.

If you struggle with your relationship with food, seeking guidance from a registered dietitian or therapist could help you develop a healthier, more sustainable approach to eating. And if you're struggling with your mental health it's essential to seek professional help like speaking to your GP, a therapist or accessing information through charities like Mind and Shout.

More wellbeing guides

The gut-hormone connection: how food affects every area of your health
Expert explains: what is the dopamine diet
Expert explains: what is the Mediterranean diet
Expert explains: what is serotonin
Expert explains: how to have a better night's sleep
10 ways to boost energy when tired
10 natural remedies for hayfever to try
10 foods to improve your mood
5 Mediterranean foods for better health
Healthiest diets from around the world
How to follow a gluten-free diet
How to follow a plant-based diet
Can you cure your cold through diet?