What are the key brain chemicals? How can you hack them to get happier?

Laurentia (Laura)Campbell
14 min readJan 8, 2021


By Laura Campbell

How to hack your brain to improve your mood. By Laura Campbell
Copyright Laura Campbell 2020

Our brains are amazing things. Our brain cells, nerve cells or neurones, are linked by neurotransmitters, which work with neurohormones, neuropeptides and hormones to help regulate our emotions and mood, memory and intelligence, energy levels, appetite and digestion, coordination and balance, immune system, senses and ability to manage stress and pain. If you can grasp a basic understanding of what the neurotransmitters, neurohormones and neuropeptides are, and what they do, you can alter your behaviour to learn to hack them for maximum benefit to your health and wellbeing (Wang et al, 2020).

Neurotransmitters are classified based upon their biochemical structure. The Amino Acid neurotransmitters comprise of those that are excitatory (Aspartate or Aspartic Acid, Glutamate or Glutamic acid) and inhibitory (Glycine and GABA). This means they stimulate or calm things. Glutamate stimulates new nerve cell growth and so has a role in memory, learning and intelligence. GABA is the main inhibitory neurotransmitter, which inhibits other neurotransmitters and neurone pathways. Too little GABA and you get anxiety. It also plays a role in motor (muscle cell) function and coordination. The next class, the Monoamines or Biogenic Peptides, consists of the Catecholamines Dopamine and Noradrenaline and the Indolamine Serotonin. Dopamine is associated with pleasure and satisfaction, it is also associated with addiction, movement, and motivation. Noradrenaline, also known as norepinephrine, is a neurotransmitter that affects attention, arousal, wakefulness, creativity, mood and blood pressure regulation. Alongside Adrenaline (Epinephrine), it is also involved in the ‘fight or flight’ stress response, and so plays a vital role in anxiety and depression and addiction. Serotonin is the mood regulation neurotransmitter that plays a role in happiness, wellbeing, appetite, sleep and feeding behaviour and is the building block for Melatonin, which is involved in sleep regulation and is deregulated in insomnia and jet lag.

We also have Neuropeptides from the Opioids Endorphins, Enkephalins and Dynorphins, to the Tachykinins Substance P, Neurokinin A and B and to Somatostatin, Oxytocin and Neurotensin. The Opioids are involved in pain modulation (analgesics) and give the sensation of euphoria (hence why exercise and sex give you a high, “runners high,”). Morphine drug and Cocaine work in a similar way. Tachykinins play a role in multiple systems, mainly addiction and pain and the immune system (which protects us from disease) and Oxytocin is the love peptide hormone and neuropeptide that stimulates love between family, friends, pets and sexual partners. Then we have the purine Adenosine (which plays a role in Circadian rhythms and sleep- it builds up during activity in the day to give the “sleep pressure” we need to fall asleep) and Acetylcholine (which plays a role in muscle movement) and Lipid Modulators Eicosanoids and Endocannabinoids (which play a role in pain, anxiety and weight loss). Finally, there is the neuromodulator Histamine (which helps regulate sleep/wake cycles).

So now we know the chemicals, but how can we hack them to make us happier and healthier? Well, let’s start with food. Serotonin is made from Tryptophan. Eating food rich in Tryptophan boosts Serotonin and Melatonin. This includes seeds and nuts, soya foods, cheese, chicken and turkey, fish and eggs. All boost Tryptophan and so help us feel happier and sleep better. Sleep plays a vital role in protecting us from disease, helping us regulate our emotions, manage stress and feel more optimistic, and helps us remember things, making us cleverer. Higher levels of Dopamine can lead to feelings of euphoria, bliss, and enhanced motivation and concentration. We can boost Dopamine by eating foods high in Magnesium (which also helps to boost energy and vitality), Tyrosine and Phenylalanine. Magnesium also plays a role in sleep and is found in foods such as spinach and green leafy vegetables, nuts and wholemeal bread. Dopamine is made from Tyrosine and foods that are high in Tyrosine include wild rice, Salmon, Beef, lean chicken breast, pork, tofu and milk. Tyrosine is made from Phenylalanine (the bliss and infatuation chemical) and so you can boost Dopamine also by boosting Phenylalanine in your diet, which is found in eggs, chicken, liver, beef, milk, and soybeans. You can also boost Dopamine via achieving things, caffeine, exercise and through sugary food. It is a balance, however, as Dopamine also has a role in addiction and too much Dopamine can lead to you becoming competitive, aggressive and having poor impulse control. It can lead to conditions that include ADHD, binge eating, addiction and gambling. Meditation, digital detoxes, yoga, sleep, low sugar foods and no caffeine or alcohol, can help reduce Dopamine.

Another way to boost your mood is to not get ill. Physical illnesses, caused by pathogenic (disease-causing) micro-organisms like viruses or bacteria can make you feel tired, unmotivated, lethargic and low as inflammation from disease (our bodies way of localising an infection), can disrupt the brain-gut axis which regulates Serotonin levels. Lower serotonin can make you feel depressed. Illnesses like colds and flu and viruses also cause fever and muscle aches which can reduce your energy and ability to exercise which reduces your mood further. Physical illness can be prevented by boosting our natural immune system. We can do this through exercise which boosts our immune system, and vitamin D from being outside and through eating a diet high in Vitamin C (rich in fruit and vegetables) and Iron (meat and spinach and pulses and fish). Iron helps boost Vitamin C absorption. Sleep also helps protect against physical illness. Some foods also have anti-inflammatory properties such as those high in vitamin A and E (berries, carrots, beetroot and turmeric). Omega-3 rich foods are also brain-protecting and anti-inflammatory. These include oily fish like Mackerel, Salmon, Sardines, Herring and anchovies and some nuts and seeds like flax seeds, chia seeds and walnuts and vegetables like broccoli, brussel sprouts and cabbage. All these foods help boost brain health and reduce the negative effects of inflammation on mood, reducing depression-like symptoms.

The brain-gut axis itself is something we can hack to get happier. This involves our gut Microbiota, the so-called “healthy” (non-disease causing) micro-organisms that line our gut. As well as a positive role in boosting the immune system and helping protect against inflammation, the gut microbiota also helps manage appetite and our stress response (Molina-Torres et al, 2019), helping us feel fuller and crave carbohydrates (Wowu et al, 2019) less and also helping us manage stress better. Recent studies, which looked at the gut microbiota role on mood (Huang et al, 2019, Humeran et al, 2019), showed the role of the gut microbiota on improving depressive symptoms. We can boost our gut microbiota through “pre-biotics” which compounds that help grow microbiota) and pro-biotics (compounds that actually contain live cultures of the microbiota that we consume and directly inject microbiota into our gut. Pre-biotics (other than specific probiotic drinks and yoghurt which are produced specifically to contain certain strains of helpful microbiota) include fermented foods like sauerkraut, pickles, miso produce (fermented soya), kefir (fermented yoghurt) and sour cream. Pre-biotics are the foods that the microbiota live off. These include high fibre foods which are non-digestible by the human gut, such as onions, leeks, garlic, chicory root, wholemeal produce, porridge bananas, apples and many more. Scientists are so invested in this idea of the benefits of the microbiota, that last year, they conned a term “psychobiotics” which are probiotic factors that improve the brain-gut health as a potential treatment for mood disorders, showing the therapeutic potential for this in mental as well as gut health (Dinan et al, 2013 and 2016).

Stress is an inevitable part of life, however, there are certain things we can do that improve our natural ability to regulate our stress response. Sleep, regular meals (without too much sugar or sweetener which causes sugar lows which make you irritable, tired and low), omega-3 rich foods, exercise and yoga, prayer and meditation (deep-breathing exercises) help us to regulate our Adrenaline “flight-or-fight” stress responses as well as the production of Cortisol. They help shift our brains from “flight-or-fight” (sympathetic nervous system activation which causes the restlessness, lack of focus, dry mouth, appetite changes, emotional swings, fear feeling, low libido and reduced ability to feel compassionate or relaxed) to the “rest and digest” (parasympathetic nervous system activation which causes feelings of calmness, empathy, creativity and sleepiness) response. These can help turn off our stress response so a stressful situation or worry does not become chronic anxiety. Cortisol is a steroid hormone that regulates a wide range of vital processes throughout the body, including metabolism and the immune response. It also makes you feel awake (and so chronic stress makes it harder to sleep). It also has a very important role in helping the body respond to stress. Deep breathing exercises are the quickest and simplest way to reduce Adrenaline and Cortisol production and calm down. Sleep decreases cortisol and also helps regulate Leptin (the hormone that makes you feel full) and a lack of sleep lowers Leptin. This is partly why stress increases your appetite. Sleep also is essential for helping us regulate our emotions and therefore our mood, which is why we feel irritable, impulsive, antagonistic and stressed with a lack of sleep.

If you are feeling low because of chronic pain, such as physical pain like chronic backache or due to an event in your life like the death of a loved one or relationship breakup, which causes chronic emotional pain, the best thing to hack is Endorphins, natural pain-killers. They are released in the brain during exercise, excitement, pain, and sexual activity, and produce a feeling of well-being or even euphoria. Some foods such as chocolate & spicy foods, can also stimulate the release of Endorphins and help you feel better. Exercise also stimulates Serotonin, helping to lift your low mood and reduce anxiety, boosts Dopamine, giving us a sensation after of pleasure, and stimulates the production of Adrenaline, giving us energy (which is why you should not exercise at night as it stops you sleeping). Exercise during the day (say a run or walk in your lunch break or cycle to and from work) also helps us sleep better (exercise at night keeps you awake). If the exercise is outdoors, it also boosts Vitamin D, which helps relate Melatonin (helping us sleep), boosts our immune system (helping to protect us from diseases) and weight bearing exercise, helps strengthen our bones (working with Magnesium and Calcium in our diet to strengthen our bones). Exercise is the most natural and sustainable anxiety and depression treatment there is.

Relationships also play a very important role in our mental and physical wellbeing. Oxytocin hormone and neuropeptide is the love chemical which causes sensations of safety, warmth, joy and love. It is the brain chemical which makes us feel love for our partner, friend or pet and it makes us more compassionate and creative and calm and less on edge. It reduces anxiety and you can increase this if your in a relationship by kissing someone, having sex, holding your partner's hand or complimenting them. If you're not in a relationship you can get it through stroking a pet, kissing a pet, hugging a friend, complimenting a stranger, kissing your mum, playing with a pet or baby, helping someone, listening to music and dancing or rubbing the tops of your arms (oxytocin rub- the tops of your arms are Oxytocin rich sites). You can also get it through laughing at comedy shows, connecting with a friend over Facebook or calling a friend, volunteering at a charity and having a sense of positive purpose and adding value and attending work team events or engaging in team sports or an art class or exercise class with a sense of community. Eggs, bananas and peppers are naturally high in Oxytocin foods too. Oxytocin improves trust, relaxation and psychological stability, boosting mood.

Alcohol is also something that needs to be considered when talking mood. We enjoy alcohol as it elevates Dopamine levels in our brain, making us feel excited and happier. This leads to increased reward drive (which is why alcohol is so addictive). It also stimulates Serotonin and decreases Glutamate. It is this that causes the lack of inhibition and memory loss, slurred speech and lack of coordination you get when you drink, and it stimulates GABA, which makes us more sedative and temporarily numbs emotions. It also works on the brain Opioid receptor and so is a traditional painkiller. However, overall alcohol is a depressive drug. It reduces your energy and vitality and overall, makes you feel sluggish, lethargic, angry, negative and low. It disrupts sleep, making it easier to get to sleep due to its sedative properties, but as it unbalances sugar levels, it makes it harder to enter slow-wave sleep and more likely for you to wake repeatedly in the night and sleep lightly. Alcohol overall, therefore, makes you feel low, made worse by the hangover the next day. If you want to boost your mood, alcohol is not your answer as the short term Dopamine high comes at a huge low on your brain and energy. It is also, like cocaine and sugar, incredibly addictive, and so you need to consume a higher and higher dose to get the same high.

The most simple way to boost mood is to boost your physical energy levels as you tend to feel more optimistic and positive when you have more vitality. You can do this artificially and temporarily with Caffeine or sugar (and suffer the crash later) or naturally with Magnesium-rich foods which boost metabolism, through exercise, through sleep and rest and also through mental stimulation. Learning a new things or being in a new environment (such as on holiday) is a great way to boost your mood as it stimulates Serotonin. It is also beneficial to your brain as it stimulates the growth of new synapses (the junctions between nerve cells) and helps stop cognitive decline. This also stops cognitive decline, which is why it is important for the elderly to continue challenging themselves mentally, to stop dementia and related brain disorders. Adrenaline is produced and Dopamine when we learn something new that we find interesting or see something new and inspiring, and these boost our mood. Foods high in iron such as red meat, spinach, beans, nuts, eggs and pork also help to boost energy and Adrenaline and overall feelings of wellbeing. Iron also helps boost vitamin C absorption (which is why you feel low when anaemic (low iron) and get ill more easily). Iodine rich foods which affect your thyroid and metabolism, (potatoes, strawberries, seaweed) and Thiamine (vit B1) rich foods (milk, beans and nuts) and B12 rich foods (mackerel, sardines, mushrooms, nuts, fortified cereals and milks) also help boost energy.

They say that we are the sum of the five people we are around the most, and it is true neurologically. We learn behaviours and mirror the behaviours of the people we surround ourselves with, based upon mirror neurones in the brain. These neurones help us with the “tribe mentality” from our caveman ancestors, enabling us to imitate and empathise with those around us (only when not in stressed state as when stressed we go all “survival mode” and focus solely on getting away from a predator, regardless of what the rest of the tribe are doing and so become selfish and sole focused), in order to build loving relationships in a tribe and promote the inter-species mating needed for the survival of the species. The purpose of a species is to survive and pass on its genes to its offspring through mating and so we are biologically programmed to want social acceptance and “follow the crowd” and act like those around us in order to help us find a mate. Therefore if you want to be happy, make yourself the happiest version of yourself and surround yourself with happy people, and you will mirror each other’s emotions, and bounce off each other, stimulating Adrenaline and giving each other positive energy. Energy levels (how much energy you literally feel you have, not some pseudo-spiritual aura) are contagious. Therefore, ensure you surround yourself with the most inspiring, stimulating, energetic and positive people you know; and you will find you become the same. The same goes with if you surround yourself with toxic “emotional drains,” you will find yourself becoming more negative also like an emotional sponge, and if you chose to have a negative attitude you will affect others. Never be the Negative Neeta, Moaning Myrtle or Crabby Chris of the group. Positivity is infectious!

Our mood is something highly unique to us. However, sun, exercise and certain foods and behaviours that we chose to do and consume, can boost our brainpower and help us feel happier and have more energy. We have far more control over our emotions, then people realise. Hack your brain chemicals to get happier and healthier.


  1. Wang, F., Yang, J., Pan, F., Ho, R. C., & Huang, J. H. (2020). Editorial: Neurotransmitters and Emotions. Frontiers in psychology, 11, 21. doi:org/10.3389/fpsyg.2020.00021
  2. Aguilar-Raab C., Eckstein M., Geracitano S., Prevost M., Gold I., Markus H., et al. (2019). Oxytocin modulates the cognitive appraisal of the own and others close intimate relationship. Front. Neurosci. 13:714 doi; 10.3389/fnins.2019.00714
  3. Gu S., Gao M., Yan Y., Wang F., Tang Y. Y., Huang J. H. (2018a). The neural mechanism underlying cognitive and emotional processes in creativity. Front. Psychol. 9:1924. doi; 10.3389/fpsyg.2018.01924
  4. Gu S., Wang F., Yuan T., Guo B., Huang J. H. (2015). Differentiation of primary emotions through neuromodulators: review of literature. Int. J. Neurol. Res. 1, 43–50. doi: 10.17554/j.issn.2313
  5. The Mount Sinai Hospital / Mount Sinai School of Medicine. “Serotonin can regulate gene expression inside neurons.” ScienceDaily. www.sciencedaily.com/releases/2019/03/190313143312.htm (accessed January 8, 2021).
  6. Mikkelsen K, Stojanovska L, Polenakovic M, Bosevski M, Apostolopoulos V. Exercise and mental health. Maturitas. 2017 Dec;106:48–56. doi: 10.1016/j.maturitas.2017.09.003. E
  7. Jenkins TA, Nguyen JC, Polglaze KE, Bertrand PP. Influence of Tryptophan and Serotonin on Mood and Cognition with a Possible Role of the Gut-Brain Axis. Nutrients. 2016 Jan 20;8(1):56. doi: 10.3390/nu8010056.
  8. de Waal FBM, Preston SD. Mammalian empathy: behavioural manifestations and neural basis. Nat Rev Neurosci. 2017 Aug;18(8):498–509. doi: 10.1038/nrn.2017.72.
  9. Huang, T. T., Lai, J. B., Du, Y. L., Xu, Y., Ruan, L. M., & Hu, S. H. (2019). Current Understanding of Gut Microbiota in Mood Disorders: An Update of Human Studies. Frontiers in genetics, 10, 98. doi.org/10.3389/fgene.2019.00098
  10. Choudhary, A. K., & Lee, Y. Y. (2018). Neurophysiological symptoms and aspartame: What is the connection?. Nutritional neuroscience, 21(5), 306–316. doi.org/10.1080/1028415X.2017.1288340
  11. Bermúdez-Humarán, L. G., Salinas, E., Ortiz, G. G., Ramirez-Jirano, L. J., Morales, J. A., & Bitzer-Quintero, O. K. (2019). From Probiotics to Psychobiotics: Live Beneficial Bacteria Which Act on the Brain-Gut Axis. Nutrients, 11(4), 890. doi.org/10.3390/nu11040890
  12. van de Wouw, M., Schellekens, H., Dinan, T. G., & Cryan, J. F. (2017). Microbiota-Gut-Brain Axis: Modulator of Host Metabolism and Appetite. The Journal of nutrition, 147(5), 727–745. doi.org/10.3945/jn.116.240481
  13. Molina-Torres, G., Rodriguez-Arrastia, M., Roman, P., Sanchez-Labraca, N., & Cardona, D. (2019). Stress and the gut microbiota-brain axis. Behavioural pharmacology, 30(2 and 3-Spec Issue), 187–200. doi.org/10.1097/FBP.0000000000000478
  14. Sarkar, A., Lehto, S. M., Harty, S., Dinan, T. G., Cryan, J. F., & Burnet, P. (2016). Psychobiotics and the Manipulation of Bacteria-Gut-Brain Signals. Trends in neurosciences, 39(11), 763–781. doi.org/10.1016/j.tins.2016.09.002
  15. Eşel, E., & Dinç, K. (2017). Alkol Bağımlılığının Nörobiyolojisi ve Tedaviye Yansımaları [Neurobiology of Alcohol Dependence and Implications on Treatment]. Turk psikiyatri dergisi = Turkish journal of psychiatry, 28(1), 51–60.




Laurentia (Laura)Campbell

Neuroscience, mental health and nutrition academic and writer. Life-experimenter, trying to add value with an insatiable appetite for actioning positive change.