What has diet got to do with my mental health?
Discussions and awareness around mental health have opened up significantly in recent years, but one area that is not often considered is the role of nutrition. When we think of food and nutrition, we often link it to our weight, trendy diets, and our physical health, but rarely do we consider it an important part of our mental health. Nutrition provides the building blocks and the fuel for our brain, as well as our body. As Dr Mark Hyman says, “food isn’t like medicine; food is medicine”.
Our mental health is dependent on several factors that are biological, psychological, social, and environmental. Some of these factors we cannot control, and others are more within our means to do so, such as our diet and lifestyle. Eating is something we do multiple times a day, but we probably don’t think about how it impacts our brain health, mood and behaviour. But if we pause and reflect for a moment, many of us will have experienced the food mood connection on one level.
Think of a time when you were eating your favourite food, whether that’s your mum’s Sunday roast, a stack of pancakes for breakfast or a slice of cake on your birthday - all I’m sure made you feel good. You may also be familiar with the term ‘Hangry’ where you become irritable due to feeling hungry. This is caused by a drop in your blood sugar levels, which then triggers the release of hormones such as cortisol (a stress hormone) and adrenaline (the fight or flight hormone) to help bring your levels back into balance.
Brain chemicals (neurotransmitters) that play a crucial role in mood are produced by the nutrients in the food you are eating, specifically from amino acids which are the building blocks of protein. Tryptophan, for example, is an amino acid that helps to create the ‘feel good’ neurotransmitter serotonin, which supports our mood, memory, and sleep. Tryptophan rich foods include turkey, oats, chicken, eggs, fish, sesame seeds, bananas, and chickpeas.
The brain itself is 60% fat, so omega 3 fatty acids found in oily fish (mackerel, salmon, anchovies) and nuts and seeds (flax, chia, walnuts) are important for cognition and brain health. Equally for your brain to be able to concentrate and focus, it needs a continuous supply of energy, with its main fuel glucose coming largely from the carbohydrates in your diet such as wholegrains, fruits, and vegetables. In fact, the brain uses 20% of all energy needed by the body. Essential vitamins and minerals are also required for different aspects of optimal mental health, especially when we are stressed or anxious, as it can leave our bodies depleted. B vitamins, for example, are essential to mental wellbeing as they cannot be stored in our bodies, so we depend entirely on our diet to supply them. A paper published in the World Journal of Psychiatry in 2018, (LaChance, L & Ramsey, D) also identified folate, iron, magnesium, zinc, potassium, selenium, vitamins A, and C as important nutrients in supporting depression There is also an increasing amount of research being carried out into the ‘gut-brain connection', which is highlighting the importance of digestive health and the role it plays in mental wellbeing. Our gut is home to trillions of organisms such as bacteria, yeasts, fungi & viruses. By including fermented foods in your diet such as kefir, sauerkraut, or kimchi as well as prebiotic vegetables (artichoke, leek, apple, garlic, and onion) you can support the gut microbiome as prebiotics help feed the friendly bacteria. There is no one set diet to recommend for good mental health but research from the HELFIMED and SMILES trials, which demonstrate dietary changes can improve mental health in people with depression, have shown that adopting the key principles of a Mediterranean-focused diet is a good place to begin. This includes, minimising or removing added sugars, refined carbohydrates, and highly processed foods and instead eating a diet rich in fruits, vegetables, legumes, and healthy fats. Whilst highlighting the connection between the food we eat and our mental health, this should not be considered in isolation from our physical health as they are inextricably linked. Although underlying mechanisms are still unclear, research shows that poor physical health significantly increases the risk of developing mental health problems and vice versa, which highlights the importance of an integrated approach to health. Mental health no doubt benefits from many facets of support and is dependent on factors such as exercise, sleep, lifestyle, and genetics but equally, I believe that nutrition is an important pillar of health to be considered. There is still a way to go but with the rise in nutritional psychiatry and an increase in quality research, I am glad to see the role of nutrition in mental health beginning to get more recognition within the public health arena.