Your Mind on Caffeine
When alertness tips into anxiety
For most of my adult life, I started my mornings with caffeine. A steaming cup of black coffee, no sugar, please.
It was part of my routine and a reliable way to feel awake and ready to work.
Recently, I began to wonder what this daily habit was actually doing for my mind. Was it genuinely helping, or just masking tiredness?
So I decided to take a break from it and look at what research says about caffeine, a substance that helps us focus but can also make the mind restless.
A contrast that makes me think about how much I depend on caffeine, and what I might be trading for the alertness it gives me!
The Caffeine Habit
It’s easy to see why caffeine becomes a fixture in daily life. Over time, the morning cup stops feeling like a choice and becomes a necessity.
The boost it gives us seems so natural, almost part of who we are…
The boost happens because caffeine works by blocking adenosine, a chemical that tells the body to rest [1]. And with that signal muted, alertness takes its place.
At the same time, it increases the release of catecholamines such as dopamine, norepinephrine, and adrenaline, the neurotransmitters that make us feel focused and ready to act [1].
The result is the familiar sense of sharpness that so many of us depend on to start the day.
What feels like energy, however, is also conditioning.
You see, the brain learns that this pattern of stimulation is rewarding. Each time we drink caffeine, we reinforce that association, making the habit both behavioural and biological.
That’s why I really felt it when I stopped caffeine altogether. The first few days (particularly days 2-4), brought headaches, heavy fatigue, and irritability.
These were withdrawal symptoms, the body readjusting as adenosine activity surged back and the stimulating effects of catecholamines subsided.
When Alertness Turns Into Agitation
If the absence of caffeine reveals how dependent the body can become, its presence reveals something very interesting: how easily stimulation can tip into strain.
What begins as focus can, with a little more caffeine, tilt toward restlessness.
At the physiological level, the same pathways that create alertness also heighten arousal. Continued blocking of adenosine keeps the nervous system from settling, while excess catecholamine activity amplifies the body’s stress response.
Heart rate rises, muscles tense, and thoughts start to speed ahead of themselves.
Again, what feels like energy is, in fact, the body’s early stress circuitry taking over.
A large analysis of experimental studies on caffeine and anxiety highlighted this transition clearly [1].
Across studies, caffeine intake was associated with increased anxiety symptoms, with the effect becoming stronger at higher doses and among individuals more prone to anxiety [1].
The pattern was consistent: at doses below 400 milligrams, symptoms of anxiety rose modestly; above that, the increase became noticeable. That is, symptoms of anxiety followed the dose, rising gradually at lower levels and sharply once intake exceeded about 400 milligrams [1].
This pattern is something many of us can observe in everyday life.
I can see traces of this in my own routine.
On busy days, a second cup of coffee seemed to sharpen my focus, until suddenly it didn’t. Concentration would give way to a jittery restlessness, a sense that I was alert but not calm.
What This Means for the Mind
Stepping back from my own experience, it’s clear that caffeine’s story isn’t one of simple harm or benefit.
While it can heighten anxiety, research also suggests it may play a supportive role in long-term brain health [Ref.].
To understand this better, it helps to separate two ideas often blurred together: Brain health is about how the brain functions and ages (memory, attention, and resistance to diseases like Alzheimer’s and Parkinson’s). Mental health is mostly about how we feel and function in the present: our anxiety, stress, and mood.
The two certainly influence each other, but they are not exactly the same.
Regarding brain health, meta-analyses have found that moderate coffee consumption (around two to three cups a day) is linked to a lower risk of cognitive disorders, including Alzheimer’s disease, with the strongest protective effect observed at about 2.5 cups per day. These findings are observational, and the association appears to vary by factors such as sex and ethnicity, peaking at moderate intake levels [Ref.].
Caffeine’s relationship with the brain/mind, then, is very intricate.
It can protect the brain from cognitive decline and momentarily enhance clarity. But it can also lead to restlessness, depending on the person and the intake.
For me, what’s become relevant now is not whether caffeine is good or bad, but whether it helps me live with a calmer mind in the now.
Concluding Thoughts
Giving up caffeine made me realise how much I rely on it to keep going.
The first few days were uncomfortable, but they also pushed me to find other ways to start the day: stretching, taking deep breaths, letting my mind wake on its own.
Science paints a mixed picture. Caffeine can sharpen thought and may support brain health, but it can also increase anxiety and disrupt rest.
Its effects depend on who we are and how much we take.
Stepping back from it has been a way of paying attention to what restores my focus, what unsettles me, and how alertness feels when it comes naturally.
As for you …
How much of your focus/energy depends on caffeine?
Reference List:
[1] Liu, Y., Zhang, J., Zhang, Y., Sun, J., & Li, Y. (2024). Caffeine intake and anxiety: A meta-analysis. Frontiers in Psychology, 15, 1399413. https://doi.org/10.3389/fpsyg.2024.1399413
When I last worked in an office, I was probably drinking the equivalent of 10-15 cups of coffee every weekday. I'm not sure how I functioned with that much caffeine in my system! I think I did it because drinking coffee was comforting and I felt I needed that comfort to deal with the intense stress of the workplace (which, of course, may have only been amplified by the ridiculous amount of coffee...).
While my consumption has significantly decreased (thank goodness!) I feel like my relationship with my morning cup(s) remains the same. It's less "I need this to wake up" and more "starting my day with coffee feels comforting, good, normal." In the afternoon, on the other hand, during that 2-3pm energy dip, that's when I say, "I'm so tired! I need coffee!"
Interesting! I have a tip for any fellow coffee fiends who’d like to (painlessly) reduce their caffeine intake. Mix half and half fresh caffeinated and decaffeinated coffee in the jar you store your coffee in. That way, whenever you make a pot you are only drinking the equivalent of a cup every 2 cups. Flavour still very satisfactory, and brain stimulation stays within sensible limits.