You’ve probably heard that old saying that you are what you eat – but did you know that your mood is also affected by the food that you eat?
The standard Western diet is packed full of processed, denatured foods which are being increasingly linked to not just obesity and heart disease but also to mental health.
What the Research Shows
A Canadian study published in 2013 reviewed the fruit and vegetable intake of a large group of participants (over 290,000) over several years. A strong correlation between fruit and vegetable intake and depression and/or other mood disorder was found and those with the highest intakes had less chances of suffering from a mental health issue.
In a 2014 review of 12 studies looking at the link between dietary habits and mental health, evidence was found of a significant relationship between unhealthy dietary patterns and poorer mental health in children and adolescents. The researchers also noted a consistent trend for the relationship between good-quality diet and better mental health.
But what constitutes a healthy diet? Here are my 5 steps to better mental wellbeing through the food you eat!
Step 1 – Avoid processed, refined foods: Unfortunately, this includes a lot of foods that regularly feature in the average shopping trolley. These include packaged meals, cook-in-sauces or packet sauces, commercial cakes, cookies, chips, pies, pastries, pastas and the like.
Lacking in nutrients due to extensive processing, these foods are often loaded with artificial additives, unhealthy fats, sugar, and excess salt and these may have an inflammatory effect on the body contributing to anxiety and/or depression.
Additionally, many of these foods are addictive, enticing you to eat large serves, whilst others may wreak havoc with your blood sugar levels which may have a knock-on effect on your mental health.
Step 2 – Increase fruit and veggie intake: The Australian Dietary Guidelines recommend 2 serves of fruit and 5 serves of veggies daily; whilst about 50% of people have no problem eating fruit, over 96% of men and 89% of women struggle to consume the recommended quota of veggies (ABS 2018).
Fruits and veggies provide a host of micronutrients such as vitamins, minerals and antioxidants. Many of these play an important role in mental health, for example magnesium deficiency is linked to many psychiatric and neuro-muscular manifestations such as insomnia and headaches as well as anxiety and depression.
Including a rainbow of colourful vegetables with main meals will help optimise your nutritional intake. Shopping at farmers’ markets is a great way to find less common fresh produce such as orange cauliflower or purple carrots.
Step 3 – Eat protein at each meal and snack: Proteins are made up of amino acids which are the important building blocks of life. Whilst the body can manufacture many amino acids itself, there are about 10 that can only be accessed through diet, especially when the body is under stress, hence the need to eat good quality protein regularly.
Amino acids make many of our neurotransmitters that affect brain functioning and mental health; for example, tryptophan is the starting unit for serotonin – our feel-good, happy hormone – which is used to make our sleep hormone, melatonin. Another example is glutamine that undergoes several processes to make our calming brain chemical, GABA.
Protein helps you feel fuller for longer and avoids fluctuations in blood sugar levels which may otherwise contribute to depression and anxiety.
Foods to include are animal proteins such as lean meats, poultry, seafood, and eggs and/or plant proteins from beans, peas, nuts, seeds and wholegrains.
Step 4 – Don’t eat sugar: Sugar is abundant in our diet. It’s not just the obvious white stuff that you need to worry about but also the hidden sugars and the many sugar aliases such as fructose, glucose, lactose, maltose, stevia, xylitol, dextrose, honey, agave, high-fructose corn syrup, maple syrup, rapadura, and cane juice. I’ve no doubt missed a few too! Plus, there are the refined foods which may rapidly break down into sugar.
When we eat a sugar-containing food or one that breaks down easily into sugar, our body releases insulin to drive that sugar into our cells. However, today’s modern diets can play havoc with your insulin and blood-sugar levels which in turn can cause hormonal issues and make you feel on edge, irritable and anxious, once the mood-lifting effects of sugar has worn off.
One of the big issues with sugar is that our bodies weren’t designed to be eating such copious amounts – maybe just some berries in the Winter months!
Higher sugar intake by way of added sugars, soft drinks, juices and pastries has been linked to depression in several studies, due the aforementioned effects on blood sugar levels and also the following:
- Lower levels of brain-derived neurotrophic factor which looks after the wellbeing of nerve cells;
- Increased carbohydrates cause a rise in inflammatory markers, inflammation has been linked to depression.
Step 5 – Enjoy natural fats: For decades we have been told that fat is bad and we’ve been bombarded with countless low-fat or fat-free products throughout supermarkets. Despite this, obesity rates and cardiovascular disease has risen dramatically. However, whilst many commercially processed fats and vegetable oils aren’t good for you, natural fats in an unadulterated form are indeed healthy for you.
Your brain needs good quality fats, such as Essential Fatty Acids (EFAs) in your diet every day. They are called “Essential” because they can only be derived from your diet or through supplementation; along with saturated and monounsaturated fats they help balance hormones and support your brain function and thus your mental health.
Healthy fats to eat include:
- Nuts and seeds;
- Oily fish, such as salmon, mackerel and sardines;
- Flaxseed oil;
- Olive oil;
- Coconut oil, coconut cream and coconut butter;
- Butter derived from grass-fed cows;
- Ghee derived from grass-fed cows;
- Organic and/or grass-fed meats;
- Organic poultry;
- Tahini (a spread made from sesame seeds).
With a bit of thoughtful planning, eating a balanced diet should be straightforward – so if you’d like to find out more and work with a nutritionist, I welcome you to make an appointment with me.
Author: Beverley Dorgan, BHSc Nutritional Medicine, ANTA.
Beverley Dorgan is a Brisbane Clinical nutritionist with a special interest in how the foods we consume can impact on our mental health from anxiety and depression to OCD and behavioural or learning issues.
Beverley is not currently taking appointments. However, to make an appointment with a Vision Psychology Clinician try Online Booking. Alternatively, you can call Vision Psychology Brisbane on (07) 3088 5422.
- O’Neil A, Quirk SE, Housden S, et al. Relationship between diet and mental health in children and adolescents: a systematic review. Am J Public Health. 2014;104(10):e31–42. DOI: 10.2105/AJPH.2014.302110
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- Australian Institute of Health and Welfare (https://www.aihw.gov.au/reports/australias-health/diet)
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- Knüppel A, Shipley MJ, Llewellyn CH, Brunner EJ. Sugar intake from sweet food and beverages, common mental disorder and depression: prospective findings from the Whitehall II study. Sci Rep. 2017;7(1):6287. Published 2017 Jul 27. doi:10.1038/s41598-017-05649-7