There seems to be an almost global pandemic of neurodegenerative diseases, such as Alzheimer’s and Parkinson’s Disease, alongside other disorders of mood, cognition and behaviour. How much of it links to our modern lifestyles, including the food we eat, has been the topic of many research papers.
In order to understand brain health, it’s key to understand the role of Neurotransmitters (NTs) - this might sound like gibberish but you’ve likely already heard of some key NTs: Serotonin (your “feel good” NT) and Dopamine (behind reward and feelings of pleasure, motivation and influences ability to plan). Much of our brain’s ability to remain healthy, and sustain a balanced mood and sharp cognition, relies on the careful balance of these chemical messengers, which allow the brain to communicate via the rest of the nervous system to send and receive messages from the rest of the body. They process sensory information, control behaviour, and are essential for mood, motivation, attention, learning, memory, and overall cognition. When these messengers are out of balance, mood and cognition suffer, and complex conditions may start to form.
There are both “excitatory” and “inhibitory” neurotransmitters. Excitatory NTs increase neuronal (brain cell) communication and in some, can have an anxiety-provoking impact, whilst inhibitory NTs reduce this communication and have a calming effect on the nervous system. For optimal functioning, there must be a balance between both influences; excessive excitation can foster insomnia, anxiety, seizures and other clinical conditions, whilst excessive inhibition can foster sedation, anaesthesia and lack of coordination.
You have likely heard of the gut-brain-axis - the gut and the brain are innately connected via both the vagus nerve, and communication between neurotransmitters - not all of which are made in the brain, but some in the gut, too. In fact, approximately 95% of serotonin is made in the gut - so it’s worthwhile noting that what you eat may help balance your brain! Production and activation of these neurotransmitters also requires a plethora of building blocks and “co-factors”, and there are certainly some key nutrients which stand out. Consuming adequate levels of amino acids (protein), Vitamin C, B Vitamins, Iron, Magnesium and Zinc can go a long way when nourishing your brain.
First up, Glutamate. Glutamate is the body’s main excitatory neurotransmitter. Remember what we said here? It increases neuronal communication, and is key for learning and memory - but can have an anxiety-provoking effect. Levels of glutamate are tightly regulated because increases can be excitotoxic (cause cell death). Generally, we don’t need to worry about low levels, as it’s readily provided for in our diets (meats, eggs, cheese, mushrooms, soya beans). However, there are certain substances which are glutamate receptor “agonists”, meaning they can mimic glutamate and produce similar, additive effects - which is largely regulated only by what we consume. This is where Monosodium Glutamate (MSG) comes in - the substance often added to processed, delivery and takeaway foods - namely Chinese food - to synthetically enhance flavour. MSG has an “excitatory” impact - for those suffering from anxiety, this is very bad news, as it can trigger symptoms. It can also increase blood pressure, and contribute to complex conditions such as Fibromyalgia. Be mindful of your consumption of MSG, especially if you have any of these conditions - often found in fast foods, especially Chinese; crisps (chips); noodles; condiments; processed foods.
Next up, GABA. GABA is the main “inhibitory” neurotransmitter - which basically means it has a calming effect on the nervous system, so may be helpful for those suffering with anxiety and chronic stress. Studies have found low GABA in those suffering from anxiety, depression, Bi-Polar Disorder, chronic headaches and a variety of clinical conditions such as alcoholism, Parkinson’s Disease and cognitive impairment - so it’s a key neurotransmitter of which we should be mindful. Vitamin B-6 is a key nutrient for the production of GABA, so it’s important to ensure you’re consuming enough B-vitamin rich foods, such as fish, whole-grains, beans and avocados. The amino acid Taurine also increases GABA, so include sources of fish, lean (and grass-fed, organic) meat and eggs, or if you’re vegan, increase consumption of legumes such as lentils and chickpeas which can be used to make Taurine, in order to increase GABA production. Personally, my favourite GABA-increased is the green tea, which contains the amino acid theanine - a GABA-enhancer! Green tea paradoxically contains both caffeine (stimulating) and theanine (GABA increasing / calming) - the resultant effect is enhanced focused, without the jitteriness that coffee can bring. Consider switching out your morning coffee for a green tea for a nervous-system calming effect, without losing your edge.
The Queen: Serotonin. Hello Mr Happy Hormone! Serotonin is arguably one of the most important neurotransmitters in the modern day (alongside GABA). It is both a mood stabilisier (thus why it’s predominantly known as our “happy hormone” for its ability to boost our mood) and helps regulate sleep, namely because it is a “precursor” to - meaning it is used to produce - our sleep hormone, Melatonin. It’s also related to various other functions, including gut motility. That said, low serotonin is associated with both depression and insomnia, amongst other disorders of mood and cognition, and might also be implicated in conditions such as diarrhoea. The amino acid Tryptophan (milk, cheese, turkey, sunflower, pumpkin and sesame seeds, soy beans) is a key precursor for Serotonin synthesis, a process which also requires sufficient Vitamin D (sunlight, eggs, fish, dark brown mushrooms) and Vitamin B-6 (beans, legumes, avocados, fish) - so be mindful to include these in your meals if you’re prone to low mood or struggle to sleep! 95% of serotonin is also made in the gut - now whilst it doesn’t have the same impact as serotonin synthesised in the brain, it may indirectly impact our mood and cognition via the vagus nerve - and locally in the gut, it impacts motility. That said, think about nourishing the gut with prebiotics (apples, oats, leeks, onions, asparagus), probiotics (fermented foods such as sauerkraut, kimchi, kefir - especially home-made kefir, see my video!), and ensure adequate fibre in the diet.
Acetylcholine: The main neurotransmitter behind memory and learning, alongside impacting alertness and motivation. This is also a key area to listen up - because acetylcholine synthesis relies on intake of choline, and given the body cannot synthesise enough of it endogenously (by itself), we should ensure we’re getting enough of it through diet. Men, post-menopausal women and lactating women are especially at risk of deficiency. You can find choline in milk, (lean, organic, grass-fed) meat and eggs, alongside chickpeas, lentils and soy beans. Although symptoms of low/ excess choline are wide-ranging and complex and best addressed by a medical doctor, if you’re feeling foggy-headed, struggling to learn and remember, you may benefit from upping your intake of choline-rich foods.
Dopamine. Welcome, pleasure messenger! Ok, Dopamine is a lot more than simply a driver of feelings of pleasure; it *is* massively involved in reward and addictions, but is also a key driver of our motivations, and ability to think and plan. When you feel good after achieving a goal - and then want to go and do it all over again? That’s dopamine. It’s also associated with our memory, ability to learn and bodily movements. That said, dopamine is the key neurotransmitter of interest in Parkinson’s Disease, known for the Parkonsonian tremor. Again, it’s all about balance: too little is associated with conditions such as Schizophrenia, Psychosis and a general lack of motivation (apathy), lethargy and depression, whilst too much is linked to poor impulse control, aggression, addictions, binge eating and ADHD . The amino acid Tyrosine is the precursor for dopamine (meaning it helps us produce it!) - found in avocados, bananas, beef, chicken and eggs. Vitamins B-3, B-6 and B-9 (Folate) are also required for efficient dopamine synthesis (avocados, beans - there’s a theme here, isn’t there?!), so be sure to ensure you’re getting the full host of nutrients required for proper dopamine synthesis and regulation.
Co-Factors: As you’ve likely seen above, most neurotransmitters require the full host of B vitamins (B-1, B-2, B-3, B-6, B-9/Folate and B-12) for both synthesis and activation. That being said, upping your intake of B-Vitamin rich foods such as avocados, legumes / beans and whole-grains, and if you’re vegan, also adding in some B-12 enriched yeast flakes, will go a long way to supporting optimal psychological, emotional and cognitive function. Furthermore, many also require Vitamin D, Vitamin C, Iron, Magnesium and Zinc. By eating a varied balanced diet rich in dark leafy vegetables, whole grains, legumes, oily fish and fruits, you will support intake of all of these nutrients.
Vitamin C: Not only does Vitamin C have antioxidant properties protecting the brain from free radicals, but it is key in various bodily processes, including the synthesis of collagen for healthy blood vessels (including in the brain), L-Carnitine (involved in mitochondrial energy and cognition), the production of various neurotransmitters, including norepinephrine (alertness, attention) and dopamine (motivation, focus) and is used by the adrenals to manufacture the hormone cortisol. Vitamin C is used by the body in large quantities during times of stress, and may positively impact brain health, cognition, mood and nervous function. It’s not, then, surprising that the highest Vitamin C concentrations are found in the brain and other neuroendocrine tissues, including the pituitary and adrenal glands which play a major role in mood, cognition and various bodily processes.
Vitamin D: Vitamin D is one of the 24 nutrients that is critical for survival, and has a role in neuromodulation, neuroprotection, neuroplasticity, and brain development. Alongside playing a role in cell division, muscle function, bone and skin health and immunity, Vitamin D plays a key role in brain physiology, namely in regulating synaptic plasticity - the brain’s ability to learn throughout life, form and consolidate new memories. It impacts various cognitive processes, including those involved in mood and mental health, and has been found deficient in various neuropsychiatric conditions. Vitamin D is also directly involved in neurotransmitter synthesis: Vitamin D3, alongside Omega-3, supports the production, release and function of serotonin, alongside the release of GABA, glutamate, glutamine and dopamine in the brain.
B Vitamins: All of the B Complex Vitamins work synergistically together to support optimal nervous system function, including assisting in synthesis and regulation of neurotransmitters, production of key enzymes, expression of genes, metabolism of nutrients into energy for the brain and overall optimal cognition (including learning, memory, focus, attention and mood), resilience to stress and protection from neurodegeneration and cognitive decline. Each have their own slightly unique roles to play.
B9: Folate and B12: Cobalamin: B9 and B12 are linked due to their complimentary roles in adjunct folate and methionine cycles.
Iron: Iron is a key cofactor for tyrosine (to produce dopamine), tryptophan (to produce serotonin) and also for the synthesis of adrenaline and noradrenaline. That being said, deficiency can impact mood, attention, motivation, reward and movement.
Magnesium: Magnesium is a master mineral for those suffering with anxiety and chronic stress. It’s key for regulating the activity of neurotransmitters in the brain, namely that of excitatory Glutamate and calming GABA, via interaction with respective receptor sites - so can support our ability to have a balanced mood.
Zinc: Zinc is an essential mineral, being a component of over 300 enzymes which rely on zinc to activate various bodily processes. Zinc also plays a key role in healthy brain development (including in DNA, RNA and protein synthesis) and function, including in synaptic transmission - communication between brain cells. Research suggests that Zinc alters both the storage and release of key neurotransmitters, including dopamine. Supplementation may support mood, cognition, learning and memory, and low levels has been implicated in conditions such as ADHD, Autism / ASD, Dyslexia, and cognitive decline, including dementias.
