It probably comes as no surprise that mental illness is very common among Australians. In fact, one in five (20%) Australians aged 16-85 experience a mental illness in any year. The most common mental illnesses are depression, anxiety and substance use disorder. This problem extends worldwide with the World Health Organisation (WHO) estimating that depression will be the number one health concern worldwide by 2030.
While many of the risk factors contributing towards developing a mental illness may be out of a person’s control such as genetics or early life trauma, the good news is that there are factors we can control to reduce our risk and also help boost our mood. More and more research is showing that what you eat can reduce your risk of developing mood disorders such as depression and anxiety in the first place and can also help improve mood in those who have been diagnosed with one of these disorders.
Poor quality diets high in processed and refined foods are associated with an increased risk of developing mood disorders, whereas better quality diets are consistently associated with a reduced risk of depression. In fact a 2018 study found that those who more closely followed a Meditteranean diet or avoided a pro-inflammatory (unhealthy) diet had a 24-35% lower risk of depressive symptoms compared to those who ate more unhealthy foods. Another study in 2017 called the SMILES trial showed that a modified Mediterranean diet- a form of a plant-based diet that contains smaller amounts of meat and dairy- could improve or even reverse depression in a small sample of people.
How does a healthy diet help improve mood?
Eating a healthier diet can have a positive effect on mood and mental health through numerous different pathways in the body. A healthy diet can help boost boost mood by:
- Having a positive effect on inflammation in the body. Depression has been associated with inflammation in the body including in the brain
- Improving an individual’s gut health including the diversity of healthy bacteria they carry . The average adults carries anywhere between 1-3kg of bacteria, viruses and fungi in their large intestine collectively referred to as the gut microbiota. Our gut microbiota play an important role when it comes to mood regulation and stress hormones
- Helping protect an important part of the brain called the hippocampus which plays an important role in helping regulate emotions as well as learning, memory and mood.
How does an unhealthy diet contribute to low mood?
Eating an unhealthy diet which contains high amounts of added sugars, sugar-sweetened beverages, processed cereal foods (e.g. white bread, nutrigrain), processed meats, trans fats, sodium (salt) and food additives such as emulsifiers can worsen mood by
- Reduces the diversity of bugs in our gut
- Shrinking the hippocampus, a part of the brain central to mood regulations
- Increasing inflammation
- Reducing the production of important brain chemicals which boost mood called neurotransmitters and
- Negatively affecting important brain proteins that protect the brain against damage and promote the growth of new brain cells
Here are our top food groups to include to help boost your mood:
Wholegrains: One of the key components of the Mediterranean diet is wholegrains. Grains, commonly referred to as ‘cereals’ or ‘cereal grains’, are the edible seeds of specific grasses. The term ‘whole grain’ is used to describe an intact grain, flour or a food that contains all three parts of the grain. Wheat, oats and rice are the grains most commonly eaten in Australia. Whole- grains are a fantastic source of dietary fibre. Fibre is the primary fuel source for the healthy bugs that live in our gut, and unfortunately less than 30% of Australian adults consume enough dietary fibre. A low fibre diet is the main driver of poor gut health. Good examples of whole-grains include:
- Dark seedy bread
- Seedy crackers
- Rolled oats
- Brown rice
Fruits and Vegetables: Diets rich in plant-based foods reduce risk of anxiety, depression and low mood. We know that poor diet can lead to chronic low grade inflammation and that fruits and vegetables are rich in anti-inflammatory compounds. Fruits and vegetables are high in a number of nutrients including a special group of antioxidants called phytochemicals as well as fibre. These are both some of the most health-promoting and disease-fighting nutrients which can only be found in plant foods. Plants contain thousands of phytochemicals which all have many beneficial roles in the body and for the brain. We also know they have a positive impact on our gut bacteria which play an important role in our stress hormones. Variety is key- a diet with a higher variety of fruits and vegetables has been shown to be more effective for improving our gut health and therefore potentially mood. Less than 50% of Australian adults eat enough fruit and less than 7% eat enough vegetables.
Nuts and seeds: Studies show that consuming nuts regularly is a positive thing to do for your brain health. In fact, nut consumption is linked to better cognitive function, improvements in mood, enhanced memory, learning and attention capacity. Nuts contain polyunsaturated fats, vitamins and minerals and phytonutrients which have essential roles in aspects of brain health. Opt for raw and unsalted varieties. Several studies have found associations between the consumption of nuts with a lower risk of depression , including the SMILES intervention trial which found improvements in rating of depression after 12 weeks of dietary modification which contained one serve of nuts per day
Extra virgin olive oil: Extra-virgin olive oil (EVOO) is one of the key components of the Mediterranean diet. EVOO is the fresh healthy juice that is squeezed directly from the olive fruit. The better the quality of the olive fruit, and faster the juice is squeezed, the higher the quality of the oil produced. Extra Virgin olive oil is 100% natural – it is not refined or extracted using any chemicals or heat, leaving it high in natural antioxidants and healthy fats. Extra-virgin olive oil is rich in special health-enhancing plant chemicals which give it its antioxidant and anti-inflammatory properties. Contrary to popular belief, high-quality extra-virgin olive oil has a high smoke point because of its lower free fatty acid content. Including EVOO in your Mediterranean style diet (at least 2–4 tablespoons) per day can help reduce inflammation.
Oily fish: Consuming more omega-3 fatty acids has a positive effect on parts of the brain that play a role in mood and memory function and are anti-inflammatory. Omega-3 fatty acids increase the levels of healthful fats available to the brain and strengthen the protective layer around nerve cells.The best dietary sources are;
- Oily fish (sardines, mackerel, tuna, anchovies)
- Cold water fish (herring, salmon, sardines)
- Nuts such as almonds and walnuts
- Flaxseed, flaxseed oil and chia seeds
Our Yellow Fish Curry - Barramundi is a great meal packed will of Omega-3!
Take home message
We are only really starting to scrape the surface when it comes to understanding the important role diet has on our mental health and wellbeing. Increasing our intake of plant-based foods such as fruit, vegetables, legumes, whole-grains, nuts and seeds and omega-3 rich foods such as oily fish, nuts and seeds can have a positive effect on mood by calming down inflammation, clearing up oxidative stress and improving our gut health. Likewise limiting our intake of processed foods, added sugars and saturated fat is important for improving our moods and mental health and protecting against anxiety and depression.
For more information:
Shop 2 / 222 The Entrance Rd, Erina NSW 2250