Four key chemicals influence our brains and bodies: dopamine, oxytocin, serotonin and endorphins. In his forthcoming book The DOSE Effect, neuroscientist TJ Power says harnessing them can revolutionise our mental and physical health and relationships. This edited extract focuses on dopamine and serotonin.
First, let’s consider how we humans have spent 99.9% of our time here on Earth. We started off deeply immersed within the natural world, surviving and thriving as tribal communities. For context, it is estimated that, for the majority of human history, we spent 85% of our time outside. Now in the modern world we are spending just 7% of our time outside.
It is fascinating to imagine how our ancestors’ brain chemistry would have been forming alongside this lifestyle. Their dopamine levels, the motivational chemical that is built through hard work and effort, would have been surging, given their constant challenging pursuit of survival. Their oxytocin levels, the connection chemical, would have been rising every day, given how essential it was for them to remain connected as a group in order to survive.
Their serotonin levels, the mood and energy chemical, would have been booming, given their days were spent outside, in nature, in the sunlight, eating unprocessed foods. And their endorphin levels, the de-stressing chemical, which is created through physical movement, would have been soaring through building, hunting and surviving as a group.
Now, let’s imagine we put hunter-gatherers into today’s world. Suddenly, they have access to sugary processed foods and their dopamine levels begin to drop. They are constantly distracted by phones and social media and their oxytocin levels fall. They begin spending all their time inside and stay awake late at night, and their serotonin levels decline. They become sedentary, sitting behind desks all day, and their endorphin levels reduce.
This is where we are at as a society right now. Many of us have lifestyles that prevent us from producing enough of these essential chemicals.
For example, when you procrastinate and scroll on your phone for hours and then feel depleted and demotivated afterwards, it isn’t a coincidence. This is your brain knowing that scrolling is not the path to the optimal future for you. So your brain will make you feel awful in order to guide you to adjust your behaviour.
The same thing happens when you eat tonnes of sugar, spend too much time inside, sit down all day, drink too much alcohol, or watch too much porn.
All of these actions, which have become a normal part of modern living, reduce our potential as a species.
Therefore, our brain chemicals will continue to send us negative messages until we listen, until we make a change.
Dopamine principles
1: Dopamine makes hard work feel good
First, we must understand the primary function of dopamine. For our former hunter-gatherer selves, dopamine was responsible for creating the drive within us to complete the hard tasks that would keep us alive. Let’s take the vital daily activity of hunting for food as an example. This activity required a huge amount of motivation and deep focus to achieve. Dopamine would rise within our brains and create a strong desire to find food.
Then, during the pursuit of hunting for it, dopamine would continue to rise as we got closer to the goal. Upon successfully hunting down an animal, dopamine would rise once again, creating a huge experience of reward and joy in our brains. This rewarding feeling would then strengthen our desire to complete this challenging activity on a regular basis, therefore maximising our likelihood of survival.
The key to understanding dopamine is that, to get it, you must focus on completing tasks that at first require effort, then gradually create a feeling of progress, thus making you really feel good after. A simple example of this could be tidying your home – an activity that is easy to put off and avoid with procrastination. However, once you eventually do it, it leads to a feeling of satisfaction and accomplishment. This feeling occurs as a result of the rise of dopamine in your brain.
2: Dopamine controls the pleasure-pain balance
Now, let’s understand how our modern world is messing up this vital brain chemical. An incredibly simple and effective way to understand this is through a brilliant concept popularised by Anna Lembke in Dopamine Nation, called the “pleasure-pain balance”. Recent neurological research has shown that the parts of your brain that experience pleasure and pain are “co-located”. This means they are located right next to each other in your brain, in an area called the hypothalamus.
This is particularly interesting as, given their co-location, they operate as a see-saw. This means that when you do hard, “painful” activities that result in either mental or physical strain, such as pushing yourself in the gym or concentrating for a prolonged period of time when working, the see-saw will be weighted on the pain side.
Let’s return to our ancestors to understand this better. Take a moment to imagine spending five hours outside, in the cold, searching for food and shelter. This would be an incredibly challenging activity. Given this difficulty, it was vital that our brains developed a survival mechanism, which ensured completing hard activities actually made us feel good.
With the see-saw weighted on the “pain” side, the “pleasure” side of the see-saw would rise, creating a rewarding, positive feeling in our ancestors’ minds. This would then lead to a reinforcement of these “painful” activities, which were essential to our survival.
Originally, the only way to increase our dopamine levels was through these hard, “painful” activities, such as hunting, foraging for food, building shelter, creating fire, and finding somewhere to live. However, over time, we quickly found ways to stimulate our dopamine system without any effort, via cigarettes, alcohol, drugs, pornography, junk food, and now, social media.
If you repeatedly exhaust your dopamine system with these behaviours for prolonged periods of time, you will experience low mood and depressive symptoms. In a low-dopamine state, you will initially feel demotivated and you will procrastinate.
Let’s return to the pleasure-pain balance see-saw. In a similar way that “painful” activities resulted in the brain experiencing “pleasure”, these activities will tip the see-saw in the opposite direction, resulting in the brain experiencing “pain”. This is simply evolution at its finest, helping us to survive.
It’s genius that we have a mechanism within our brains that rewards us when we engage in the key behaviours that increase our likelihood of survival and makes us feel bad when we engage with those that reduce our likelihood of survival.
During these highly pleasurable dopaminergic activities, your brain also produces an incredibly intelligent additional neurochemical called dynorphin. In order to further dissuade you from engaging too much in them, dynorphin is released, creating discomfort in your brain. This discomfort may be experienced as depressive feelings and severe low mood – the kind of feeling that occurs the day after drinking too much alcohol, eating too much sugary food or scrolling through social media videos for too long.
Our goal is no longer the pursuit of hunting animals or building shelter. Now, your pursuit will become your dreams, your passions, your relationships and the health of your body and mind.
Burn-out
When you repeatedly spike and crash your dopamine levels, it exhausts your dopamine system. If you got in your car every morning and revved the engine for five minutes without putting it into gear and driving it, you know this would burn out the engine. In a similar way, many of us are now burning out our dopamine systems with pleasurable behaviours. This is a primary cause of the demotivated, depressive symptoms you may experience in your life.
The six primary behaviours that will cause your dopamine levels to reduce are: sugary foods, alcohol and drugs (including vapes), pornography, social media, gambling and online shopping.
Any of these behaviours result in significant spikes and crashes in your dopamine system. These quick spikes in dopamine are what make these behaviours incredibly addictive.
When looking at your capacity to resist engaging with the addictive behaviours you find pleasurable and ensure you incorporate the effortful daily activities that you know will benefit your future, we must consider how strong your willpower is.
The science of willpower is fascinating and something that we all desperately need to strengthen to thrive in our modern world. Willpower can be defined as your ability to resist short-term temptations in order to achieve your long-term goals.
To give you a simple example of this, if you decided your long-term goal was to eat healthier food and improve your physical health, then resisting chocolate and biscuits and selecting natural foods would serve this mission of yours.
Now, the science: there is a specific area of your brain called the anterior mid-cingulate cortex, or aMCC. During any moment in which you either resist an addictive behaviour or intentionally engage with a healthy behaviour, this component of your brain will light up.
What is fascinating here is the more often it lights up, the stronger it will become, in a similar way that going to the gym and doing bicep curls will strengthen your arms. With each rep, your arms get stronger. With each activation of your aMCC, your willpower will get stronger.
What’s interesting is that as this component of your brain gets stronger, your ability to maintain discipline gets easier. If, for example, you finish work and think, “I should go to the gym,” and your brain counters with, “Ahhh, but I can’t be bothered,” but you still force yourself to do it, your aMCC will light up and strengthen, which in turn makes the next time this negotiation occurs in your mind a little bit easier to win.
You know when you meet one of those really disciplined people, who eats well, exercises lots, works hard and you think, “How on earth are you doing this?” That person has activated their aMCC.
Seratonin & the gut-brain axis
Serotonin is a magical chemical that, when activated correctly, empowers you towards a much healthier experience of life. The best way to understand serotonin is to think of it as the chemical that will help you to take good care of your body. Having a calm, healthy, energised body is essential to experiencing true joy within our minds.
The most important aspect of serotonin for you to understand is that this chemical is not entirely created within your brain. In fact, 90% of it is produced within your gut. The serotonin that is produced in the gut has been shown to directly affect our mood, energy, emotions and nervous system function. This provides a very clear insight into the importance of caring for [your gut]. The happier your body, the happier you will feel in your mind.
For many of us, when we experience challenging emotions such as sadness, worry or low mood, we feel uncomfortable and we will try to distract ourselves from these feelings, believing it is the easiest route to take. An example would be feeling sad and choosing to eat some sugary food, or to scroll through social media to take your mind off the emotion.
As we know from the dopamine section, engaging with these “quick dopamine” behaviours only exacerbates the problem. I want you to keep an important concept in mind: these feelings are coming up within you for a reason. When you observe them closely, you may notice a lot of them are “gut feelings”. They feel like they are coming from your body, and they are. They are simply messages that are trying to shift how you are living your life.
Your brain and body are incredible at survival: that is their primary objective, to stay alive and pass on your genes. Just as healthy behaviours provide a rewarding feeling within you to reinforce doing them more regularly, unhealthy behaviours provide a negative feeling to try to stop you engaging with them so often. Start listening to your emotions. The more you listen to and align your daily behaviour to your emotions, the happier and healthier you will become.
Brain-body connection
Each of us has 12 cranial nerves: these are the primary nerves that start at the top of your spine and communicate with your brain to cover various functions such as eyesight, taste, hearing and much more. Eleven of these nerves go from the top of your spine and travel upwards into your brain. One nerve travels downwards. It makes its way down into your throat, then into your chest, then into your abdomen. This nerve is called the vagus nerve (see “Breathe in vagus”, here). It was given this name from the Latin word vagus, which means “wandering”, because of its extensive connections around your body.
The vagus nerve enables communication between your gut and your brain, and is constantly assessing the state of your body. For example, it monitors your heart rate, breathing, digestion, mood, energy levels and immune system.
If your body is being treated in the healthy way it desires, this will have a direct impact on how you feel emotionally.
This is where things get really interesting, because the term “mental health” leads us to think this is all something occurring in our brains.
It is clear, however, that your body also has a huge impact on the experience you have in your mind each day.
If your serotonin levels are low, you will often experience nervousness, anxiousness, low mood or low energy levels. Remember, it is not unusual if you are struggling with these symptoms; it is natural and many of us are.
The key is gaining awareness and then beginning to incorporate behaviours that provide the solution.
Now, consider which of the following four causes of low serotonin may be affecting you:
An unhealthy processed diet
This one is simple to understand. Serotonin is created in your gut. If healthy, nutritious foods arrive in your gut, your gut thinks, “Great, I can easily create serotonin from this food.” However, if unhealthy, sugary, fatty foods arrive in your gut, it has to spend time simply trying to eradicate those foods from the body. Building serotonin becomes the last of its priorities.
I’m sure you’ve experienced this yourself. You eat some unhealthy food, you experience a huge spike of dopamine in your brain from the sugar and initially it feels amazing. After you have finished eating, as your body digests the food, you experience a dip in your mood and energy levels and you crave more processed foods for another hit.
Lack of quality sleep
This is now a common problem. Many of us have highly demanding jobs and, alongside that, deep addictions to our technology (I include myself here). Staying up late in the evenings on our phones, checking them at night and scrolling through them as soon as we wake up creates a huge range of challenges for your neurobiology.
In our ancestors, serotonin would have been optimised to a high level. We know their dopamine was fulfilled through the constant pursuit of survival. Their oxytocin was fulfilled by their deep requirement for love and connection as groups. With their serotonin, we must consider how their bodies were treated:
They would wake up in the morning to bright, natural light, while being immersed within a natural environment.
They would hear the birds, the animals and the sound of nature around them. They would explore their local environment, in the pursuit of food, water, tools, shelter or new places to live. In order to survive, they built a connected relationship with nature.
They would eat unprocessed food from the land, and drink fresh water that came from the rivers and mountains around them.
They would sleep deeply at night with no access to artificial light. This is what serotonin wants.
Lack of time in nature
Unsurprisingly, having evolved over 300,000 years traversing the natural world, your neurobiology is deeply designed to experience a close connection with the natural world and a great deal of sunlight.
Our digital way of living is progressively leading to the majority of our time being spent indoors. Alongside this, more and more of us are not prioritising spending time in natural environments.
Lack of sunlight
This, of course, is caused by lack of time in nature. Any exposure to daylight, whether you’re in nature or not, is incredibly beneficial for your serotonin levels.
