Nutrition – What You Need To Know About Staying Mentally Healthy
Nutrition – What You Need To Know About Staying Mentally Healthy
We know that our diet and our mental health are inextricably linked. Extensive research has demonstrated that good nutrition is associated with better mental health outcomes and a poor diet can lead to a number of different conditions such as depression and anxiety.
But why is this so? And what can we do about it? Read on to find out more about how you can modify your diet to support your mental health.
How the Gut-Brain Axis impacts your mental health
The enteric nervous system (ENS), also known as the second brain or the brain in your gut, is made up of two thin layers of more than 100 million nerve cells that line your gastrointestinal tract and transmit messages to the brain in our head.
The gut-brain axis is a bidirectional communication network that links the enteric, central nervous systems and our gut microbiome. It also includes endocrine, humoral, metabolic and immune communication pathways. The autonomic nervous system, hypothalamic-pituitary-adrenal (HPA) axis and nerves within the gastrointestinal (GI) tract all link the gut and the brain.
The gut produces many of the same neurotransmitters as the brain does, like serotonin, dopamine, and gamma-aminobutyric acid, all of which play a key role in regulating mood. In fact, it is estimated that 90% of serotonin is made in the digestive tract. 
The gut microbiome helps us digest food and regulate our immune system. As gut microbes change so too do the metabolic compounds in the gut.
Gut microbes produce a variety of metabolites that modulate brain function, including:
- Neurotransmitters such as gamma aminobutyric acid (GABA), serotonin, norepinephrine, and dopamine
- Short-chain fatty acids, including butyrate and propionate
- Indoles, compounds derived from the amino acid tryptophan that have anxiety-promoting properties
- Bile acids
- Choline metabolites
- Vitamins including biotin and B12 
These metabolites stimulate the vagus nerve, the immune system and are directly absorbed into the bloodstream, impacting the emotional and cognitive centres of the brain, influencing our moods and mental health.
Several mood disorders, such as anxiety, depression and autism spectrum disorders are linked to gastrointestinal dysbiosis and disease states, such as irritable bowel syndrome and irritable bowel disease, are impacted by the condition of the gut microbiome. 
Diet and mental health
Our diet is key in influencing the gut microbiome’s impact on cognitive function and overall mental wellness. This is good news as if we are experiencing mental health issues, our nutritional habits, dietary patterns and diet quality can be modified to improve the state of our mental health.
The traditional Western diet is highly processed and full of refined carbohydrates and sugar. Research tells us that this inflammatory diet increases our risk of developing symptoms associated with depression and anxiety particularly in an inflammatory gut microbiome, promotes nutrient deficiencies and increases intestinal permeability (leaky gut). 
Leaky gut affects our ability to properly digest and absorb nutrients, which, over time, can lead to vitamin deficiencies.
The most common mental disorders that are currently prevalent in numerous countries are depression, bipolar disorder, schizophrenia, and obsessive-compulsive disorder (OCD). The dietary intake pattern of the general population in many Asian and American countries reflects that they are often deficient in many nutrients, especially essential vitamins, minerals, and omega-3 fatty acids. 
What should I be eating for my mental health?
Studies suggest that the risk of poor mental health is lower if we follow an anti-inflammatory, Mediterranean-style diet. A balanced diet of vegetables, fruits, healthy fats, lean proteins, and whole grains and regularly scheduled meals will assist in managing mental wellness. Evidence indicates a link between high fish consumption and low incidence of mental disorders due to a low intake of omega–3 fatty acids.
The most common nutritional deficiencies seen in patients with mental disorders are omega–3 fatty acids, B vitamins, minerals, and amino acids. These are precursors to neurotransmitters.
To help your brain function properly, eat a variety of foods that are rich in essential nutrients, including:
- vitamin C: citrus fruits, leafy green vegetables, and other fruits and vegetables
- vitamin D: salmon, cod, shrimp, eggs, and fortified milk, juice, and cereal products
- B vitamins: red meat, fish, eggs, dairy products, whole grains, and leafy green vegetables
- magnesium, selenium, and zinc: nuts, seeds, whole grains, green vegetables, and fish
- complex carbohydrates: starchy vegetables, such potatoes, corn, peas, and winter squash
- tryptophan: lean red meat, poultry, eggs, and beans
- phenylalanine: lean red meat, chicken, eggs, dairy products, soybeans, and seeds
- omega-3 fatty acids: salmon, trout, tuna, beans, walnuts, broccoli, cauliflower, spinach, cantaloupe, chia and hemp seeds, and canola and flax seed oil
- omega-6 fatty acids: poultry, eggs, grains, and vegetable oils. 
The importance of healthy fats for our brains
Healthy fats are essential to brain health as our brains constitute 60% fats.
Healthy fats include essential fatty acids such as omega 3s, 6s and 9s from plant foods such as olive oil and olives, nuts, seeds, and oily fish, but also healthy saturated fats from grass fed, free-range meats, coconut sources and eggs. These fats can help to reduce inflammation in the brain and are needed for balanced hormone production, both of which contribute to our mental health state.
Our brain requires as much as 25% of our energy intake each day. Brain fuel can come either from glucose, or fats in the form of ketones, which are made in the liver from fats. Ketones are often easier for the brain to use than glucose. 
Probiotics and mental health
Some research has found that probiotics may help boost mood and cognitive function and lower stress and anxiety. Experts believe microorganisms living in your gut, including probiotics, play a crucial role in the gut-brain-axis by:
- producing and expressing neurotransmitters that can affect appetite, mood, or sleep habits
- reducing inflammation in your body, which can contribute to depression
- affecting cognitive function and your response to stress 
Research shows that Lactobacillus and Bifidobacterium bacteria are the most helpful for mental health. You can buy a probiotic blend and you can eat more probiotic such as yogurt, tempeh, kimchi, miso, tofu and sauerkraut.
Eat whole foods instead of processed foods
A whole foods diet improves mental health by:
- Reducing inflammation with natural antioxidants, polyphenols, vitamins, minerals, healthy fats in natural foods, and the absence of processed and refined carbohydrates
- Increasing nutrient density with high antioxidant, polyphenol, vitamins, minerals, healthy fats found in whole foods
- Improving gut health, as the presence of fibre, and diversity of nutritional, prebiotic and probiotic compounds found in whole foods nourish gut health 
Drink plenty of water, preferably filtered water, every day to detoxify your body, improve circulation and optimise your brain function.
Dehydration increases your levels of the stress hormone cortisol. If left unmanaged, chronic stress and high cortisol levels can trigger numerous brain health problems and lead to:
- A loss of brain cells
- Decreased brain size
- Disruption of your brain synapses, leading to psychological problems like social withdrawal and isolation 
Limit caffeinated drinks, such as tea, coffee and alcohol as they cause dehydration.
Eat more herbs and spices
Herbs and spices are a great replacement for salt and have many health benefits. They are full of antioxidants, anti-inflammatory compounds, polyphenols, vitamins and minerals. Try using herbs such as parsley, coriander, rosemary, thyme, dill and oregano, and spices such as turmeric, pepper, ginger, chilli, cinnamon and cumin.
What foods should be avoided to ensure good mental health?
Eating too many refined and processed foods, sugary foods, and deep-fried foods increases your risk of mental health issues, as well as physical health issues. They are high in calories and low in brain-healthy nutrients.
Reduce or cut out refined carbohydrates if you can. Sugar and white flour products can cause insulin resistance, hormone imbalances and inflammation. Instead of refined carbohydrates, you can eat complex carbohydrates from starchy vegetables, fruits and whole grains. Whole grains to try include brown rice, quinoa and buckwheat but emphasise starchy vegetables over these..
Gluten and dairy have been found to provoke high intolerance levels, which can cause systemic inflammation, and lead to intestinal permeability and neuro-inflammation.
Limit alcoholic beverages as they have a number of different negative health impacts for mental health. Not only does alcohol have a high sugar content, but it can also disrupt your hormones, impact your sleep (which is critical for good mental health) and can raise cortisol (the stress hormone we want to lower).
How we can help
Good mental health requires a number of lifestyle factors to be working together well. Good sleep habits, a good amount of exercise, low stress levels and perhaps most importantly, balanced biochemistry & neurotransmitters, gut health and nutrition. These aspects are key to ensuring good gut health and optimised biochemical pathways, which in turn, is vital for optimal brain function.
At Advanced Functional Medicine, we can work with you to create a customised balancing plan based on your personalised tests results that will help support your mental health.. Call us to find out more.