You know what to eat. Your clients probably do too.
They know vegetables are better than biscuits. They know late night snacking isn’t helping. They know that the third coffee isn’t really about caffeine. And yet, knowing doesn’t seem to change much.
This is one of the most frustrating paradoxes in coaching. You can give someone the best information in the world and watch them do absolutely nothing with it. Not because they don’t care, and not because they aren’t trying. But because the brain doesn’t actually learn from instruction. It learns from experience.
Understanding why this is the case changes everything about how you coach.
Two brains, one body
Neuroscientist and psychiatrist Dr Judson Brewer describes the brain as having two operating systems. The old brain and the new brain.
The old brain is ancient, fast, and automatic. It evolved to keep us alive in a world of scarcity and danger. It runs on a simple but powerful process called reward-based learning: do something, feel good, remember it, repeat. This loop is so fundamental to survival that scientists have found it operating in sea slugs, creatures with only 20,000 neurons in their entire nervous system.
The new brain, the prefrontal cortex, is the part we tend to think of as “us.” It handles logic, planning, decision-making, and what we commonly call willpower. It is younger in evolutionary terms, more sophisticated, and considerably more fragile.
David Rock, in his book Your Brain at Work, paints a vivid picture of just how fragile. He uses the metaphor of a stage in a small theatre, where the actors represent the information your brain is actively working with at any given moment. The stage represents where you direct your focus, and it needs a lot of lighting, meaning a great deal of energy, to function at all. The problem is, the prefrontal cortex is extremely energy-hungry, easy to exhaust, and its limited resources must be utilised with the greatest of care.
Rock goes further. We have limited resources for activities like decision-making and impulse control, and when we use these up, we have less available for the next activity. This is not a motivational problem. It is a neurological one.
When the stage empties
Here is where it gets important for coaches.
The prefrontal cortex goes offline when needed most, specifically under stress, hunger, and tiredness. This is precisely the moment when your client’s eating behaviour becomes most automatic and most difficult to change. The rational, goal-oriented thinking they were relying on disappears, and older, more automatic patterns take over.
Brewer makes the same observation from a different angle. Willpower strategies fail precisely when they are needed most. And this is not a coincidence. Each time you inhibit something, your ability to inhibit again is reduced. Every act of restraint draws from the same limited pool. By the time your client reaches the end of a long, stressful day, that pool is empty.
Telling a client to “just try harder” is asking the weakest system in the brain to fight the strongest one.
The loop that runs without permission
While the new brain is busy managing work, relationships, decisions, and distractions, the old brain is running a very different programme.
Brewer describes it as the cue-craving-response-reward loop. A trigger fires, a craving follows, a behaviour occurs, and a reward lands. The brain logs it. Over time, the loop becomes automatic, running below conscious awareness, requiring no decision-making at all.
The basal ganglia is a machine at recognising and engaging in repetitive patterns. Once a habit is grooved into this region, it runs on autopilot, and the prefrontal cortex, already stretched thin, barely registers it happening.
This is why your client can walk to the pantry, open it, and eat something before they have even made a conscious choice to do so. The loop didn’t ask for permission. It never does.
The modern food environment makes it worse
The old brain evolved in a world of food scarcity. It learned to treat calorie-dense food as a survival priority, tagging it with dopamine to ensure it would be remembered and sought again.
Companies have tweaked their products so they hit that bliss point mix of salt, sugar, and fat that signals to the body that what is in the mouth is packed full of calories. Convenience, food engineering, and emotions add up to make it really easy to get locked into poor eating habits.
The old brain cannot distinguish between 50,000 BC and now. It sees calorie-dense, hyper-palatable food and responds exactly as it was designed to. The habit loop fires, dopamine reinforces it, and the new brain, already running low on resources, rarely intervenes in time.
Rock’s research adds another layer here. Being always on, connected to others via technology, can drop your IQ significantly, as much as losing a night’s sleep. Your client is not just contending with food cravings. They are making food decisions on a prefrontal cortex that has been eroded by a full day of cognitive load, emotional demands, and digital noise. The deck is stacked.
The brain learns from direct experience, not instruction
This is the shift that changes how you coach.
Telling a client what to eat, when to eat, or why they should stop eating a certain thing is appealing to the new brain. It feels productive. It looks like coaching. But if the behaviour is driven by an old brain habit loop, the information never reaches the part of the brain that actually needs updating.
The brain updates through direct experience. It needs to feel the difference, not understand it intellectually. This is why Brewer’s approach centres on awareness and curiosity rather than rules and restriction. When a client actually pays attention to how they feel before, during, and after a habitual eating episode, the old brain gets new data. It starts to question whether the reward is as good as advertised.
Rock supports this too. Increasing the amount of adrenaline in the brain actually serves to decrease the amount of dopamine, further hampering the learning process, which is why minimising threat responses is so important when learning is the goal. A client who feels judged, shamed, or pressured is not in a state to learn anything new. Their stress response is up, their dopamine is down, and the old brain is firmly in charge.
Curiosity, it turns out, is a more powerful intervention than instruction. Not because it sounds nicer, but because it engages the brain’s learning system in a way that talking never can.
What this means for your coaching
It means your job is less about transferring knowledge and more about creating conditions for your client’s brain to have new experiences.
It means asking better questions rather than offering better answers. It means helping clients notice what is actually happening in their body before they eat, rather than telling them what they should eat instead. It means understanding that a setback is not a failure of motivation, it is a habit loop doing exactly what habit loops do.
Rock describes metacognition, thinking about thinking, as one of the most powerful tools available to the brain. This occurs not only at a cognitive, conceptual level, how do I think, but also at a more visceral, immediate level, what am I thinking and feeling at this moment, and is it useful. This is precisely what great coaching cultivates. Not more information. More awareness.
When clients understand that their behaviour is not a character flaw but a predictable output of ancient wiring meeting a modern environment, something shifts. The shame reduces. The curiosity increases. And that is when real change becomes possible.
Because the brain doesn’t learn from instruction. But it learns remarkably well when it finally feels safe enough to pay attention.