How does food affect your mental health?

food and mental health

Are you living the life you want to live? We at Gut Well Soon know that a patient’s lifestyle can act as both a cause and a potential solution to many mental ailments. Our founder Catherine has had multiple years of experience working in the field of mental health, having been trained in CBT at Oxford University, and she believes strongly that physical health is a key element to  successful recovery. Whether you are suffering from depression, anxiety or chronic stress, or just want to find out more about the link between brain and body, your diet can be tailored in order to support a two-pronged approach to mental health and to treat the body as a complete and complex organism. Read on to find out more about the link between food and mental health, and discover the best foods to treat anxiety and depression.

The first question: Does what you eat actually affect your mental health?

The short answer, as you may already have guessed, is: of course it does! The brain is hugely vulnerable to negative nutritional input: it requires balance to help clear out waste products from the normal metabolic processes in the brain. If your diet is deficient in key micronutrients, your brain cannot function normally and your sensory capabilities cannot be fully deployed. Bad nutrition, poor exercise and stressful environments can all play a part in contributing to burnout, fatigue and other mental health issues.

What should I be eating to support my mental health?

Dr Kellner, in The Whole Brain Diet, looks at a healthy microbiome as the solution to ‘healing depression, anxiety and brain fog without prescription drugs.’[1] A study from the University of Oxford has recently shown that a prebiotic intervention can increase one’s attention to positive stimuli, a proxy marker for optimism, clearly implicating that our gut impacts our mood.[2] Prebiotic foods contain indigestible fibres which promote the growth of beneficial bacteria in the intestine; examples of some delicious prebiotics to introduce into your diet include garlic, onion, asparagus, leek, radishes and banana.

It is also essential to eat plenty of anti-inflammatory foods in order to guard against deficiencies of B12, magnesium, zinc and fatty acids, all of which are essential for energy and mood regulation. These include green vegetables, berries, nuts, seeds, mushrooms, garlic and olive oil. Eating dark chocolate and spicy food is also believed to help your body release endorphins.

Fruits and vegetables are a key component in a balanced diet, and ideally we should all be eating 5+ servings per day: they contain compounds called phytonutrients which have anti-inflammatory properties and feed the all-important bacteria in your microbiome.

What foods should I avoid?

It shouldn’t come as a surprise that junk food affects mental health, as eating excessive amounts reduces diversity of bacteria in the gut. Tim Spector, a professor who challenged his son Tom to eat only McDonalds for 10 days, found that Tom lost 1,400 bacterial species from his intestine – almost a third of his microbiome![3] And there is now significant evidence that a lack of species diversity in the gut can be a risk factor for developing mental health problems such as depression and anxiety.[4]  

As a starting point, try to reduce your consumption of foods rich in processed fat and sugar, which alter the composition of the gut bacteria, resulting in an imbalance that may disrupt mental health. The glycaemic index (GI) can be used to help you decide which foods you should be incorporating into your diet and which are best to avoid. A low GI food (ranking 55 or below) will deliver sugar into your bloodstream far slower than high GI foods, which will cause a rapid blood sugar spike followed by a ‘sugar crash’.

Does this mean no caffeine, sweets or treats for the rest of time?

Reset Your Health advocates a ’80-20’ approach to healthy eating. This means that if you are eating well 80% of the time, then it is absolutely okay to eat whatever you want for the remaining 20% -after all, we all want to be able to enjoy life to the fullest! However, the Reset Your Health Plan involves a week of cutting out sugar, alcohol, processed food, gluten and dairy. This is to give your gut the chance to rest and repair, so that you can find out if any particular food groups are causing unwanted symptoms.

How else can I best support my mental health?

Catherine supports a multi-layered, holistic approach to mental health. She argues that solutions are unlikely to be unilateral – it is more likely that a number of changes, made over a period of time, will have a lasting and successful effect. This might include dietary changes, but it might also include talk therapy, exercise, redefining sleeping habits and mindfulness or meditation. Everyone’s mental health journey is different, and it is important to be patient with yourself as you embark upon yours.

If you are interested in the link between food choices and mental health, why not take a look at the Reset Your Health programme? Our focus is on investigating ways in which your food choices can help you take control of both the mental and physical aspects of life. Designed to advocate a more complex and mindful approach to eating, Reset Your Health might just be the answer to all your wellbeing questions.


[1] Kellman, Raphael, The Whole Brain Diet (London: Scribe UK, 2017), p. 12.

[2] Schmidt K, Cowen PJ, Harmer CJ, Tzortzis G, Errington S, Burnet PWJ. Prebiotic intake reduces the waking cortisol response and alters emotional bias in healthy volunteers. Psychopharmacology (Berl). 2015;232(10):1793-1801.

[3] Spector T. My dad asked me to eat McDonald’s for 10 days. This is what happened. The Telegraph. http://www.telegraph.co.uk/foodanddrink/11603430/My-dad-mademe-eat-McDonalds-for-10-days.-This-is-what-happened.html. Published 2015.

[4] Foster JA, McVey Neufeld KA. Gut-brain axis: How the microbiome influences anxiety and depression. Trends Neurosci. 2013;36 (5):305-312.