Feeding your mind: The link between food and mood

The connection between diet and mental health has gained considerable interest in recent years, with research suggesting that our diet can significantly impact our psychological wellbeing. The concept of ‘mood food’ has even developed into a recognised academic field known as ‘nutritional psychiatry’ with a greater focus on uncovering the link between what we eat and how we feel.

Studying the relationship between diet and mental health can be challenging because our food choices and mental state have a two-way interaction. What we eat can influence our mood, but our emotional state can also impact our eating habits; take the common occurrence of comfort eating, for instance.

Moreover, the interplay between our diet, physical health, and mental wellbeing is complex. A poor diet can lead to health issues like obesity and type 2 diabetes, which are well-recognised to harm mental wellbeing. The effect of diet on symptoms of depression and anxiety is notable due to the high prevalence of these conditions.

Studies show that following a healthier diet, such as the Mediterranean diet, can lower the risk of depression compared to a standard Western diet. Trials such as the SMILES (Supporting the Modification of Lifestyle in Lowered Emotional States) and AMMEND (Mediterranean Diet for Men with Depression) studies suggest that dietary interventions based on the Mediterranean diet can significantly benefit adults with depression.

The Mediterranean diet has several characteristics that may explain its potential impact on mental wellbeing – which include:

1. Low sugar and refined carbohydrates

Diets high in refined carbohydrates and sugars (reflected by a high glycaemic index) can negatively affect mental health and cognition, which is likely due to the rapid and frequent fluctuations in insulin and blood sugar levels. On the other hand, diets that are low in sugar but high in fibre, like the Mediterranean diet, have a lower glycaemic index and lead to more stable blood sugar levels.

2. High anti-inflammatory content

The precise link between inflammation in the body and mental wellbeing is unclear. However, diets high in foods that promote inflammation, such as saturated fats, appear to harm mental health. Conversely, diets rich in anti-inflammatory agents such as omega-3 fatty acids (oily fish), antioxidants, and polyphenols (olive oil, fruits, and vegetables) benefit our psychological wellbeing.

3. Promotion of a healthy gut microbiome

There has been a surge in interest in how diet affects the gut microbiome, which consists of trillions of microorganisms. This curiosity stems from the growing fascination with how these microorganisms impact the neuronal communication between the gut and brain – also known as the ‘gut-brain axis’. Diets like the Mediterranean diet, which are high in fibre, polyphenols, and unsaturated fatty acids, help promote a healthier gut microbiome. One animal study published in the Journal of Psychiatric Research suggests that altering the gut microbiome may significantly affect mood and behaviour.

Working together to protect health

Zurich Evolve is our approach to health with a focus on diet as one of the core foundations for healthy living. Studies show making changes to your diet can have a positive impact on your mental health as well as play a role in managing conditions like diabetes and obesity. Wherever you may be in your journey, we’re here to help you stay healthy and feel healthier with Zurich Evolve.

A randomised controlled trial of dietary improvement for adults with major depression (the 'SMILES' trial). Jacka FN et al. BMC Med. 2017 Jan 30;15(1):23
The effect of a Mediterranean diet on the symptoms of depression in young males (the "AMMEND: A Mediterranean Diet in MEN with Depression" study): a randomized controlled trial. Bayes J, Schloss J, Sibbritt D. Am J Clin Nutr. 2022 Aug 4;116(2):572-580
3 Transferring the blues: Depression-associated gut microbiota induces neuro behavioural changes in the rat. John R Kelly et al. J Psychiatr Res. 2016 Nov; 82:109-18